Automatic Transaxle Diagnosis - 4t40-e & 4t45-e Chevrolet Cavalier III

APPLICATION

Note. For diagnosis of transaxle electronic control system on Saturn "L" series equipped with 3.0L V6, see HYDRA-MATIC 4T45-E ELECTRONIC CONTROLS - SATURN "L" SERIES V6 article.

AUTOMATIC TRANSAXLE APPLICATIONS

DESCRIPTION & OPERATION

The Hydra-Matic 4T40-E and 4T45-E transaxle uses 2 electronic shift solenoids, controlled by Powertrain Control Module (PCM), to control shifting and a pressure control solenoid to control hydraulic pressure. Torque Converter Clutch (TCC) solenoid is a Pulse Width Modulated (PWM) solenoid which controls TCC apply and release. Each solenoid is turned on or off by PCM. PCM includes on-board self-diagnostics. Self-diagnostics feature helps identify which components or circuits may need further testing.

Each solenoid either holds hydraulic pressure (solenoid on) or releases hydraulic pressure (solenoid off). Solenoid operation controls shift valves inside valve body. By switching one or both solenoids on or off, different combinations of clutches, sprags and bands are operated. See SOLENOID POSITIONS table. Line pressure is increased or decreased by PCM changing duty cycle on pressure control solenoid.

Line pressure control system compensates for normal wear of transaxle components during upshifts in order to maintain optimal shift quality during life of transaxle. PCM uses "adaptive learning" to maintain acceptable upshift times by adjusting line pressure. PCM compares actual "acceptable" shift time to calibrated desired shift time and calculates difference. An "acceptable" shift is considered valid if no inconsistent vehicle operations (A/C compressor cycling or extreme throttle changes) occurred during upshift. Line pressure is either increased or decreased depending on duration of upshift time.

SELF-DIAGNOSTIC SYSTEM

PCM constantly monitors all electrical circuits. If PCM detects circuit faults or sensors out of range, it will record a Diagnostic Trouble Code (DTC). If fault continues for a predetermined time, Malfunction Indicator Light (MIL) will illuminate.

If MIL is on all the time, DTC(s) are currently being detected. If MIL is off, but PCM had detected a circuit or sensor fault, DTC(s) will be stored in computer memory.

Stored DTCs may be retrieved from PCM memory using a scan tool. DTCs CANNOT be retrieved by grounding 16-pin Data Link Connector (DLC).

Note. Faulty engine sensors and actuators may cause transaxle related DTCs or driveability problems. Engine faults and related DTCs must be diagnosed and repaired before transaxle DTCs are repaired. For additional information on diagnosing and repairing engine related PCM DTCs, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

PCM

On"J" body models, PCM is located forward of right front wheel housing, behind front fascia cavity splash shield. On "N" body models, PCM is located below left side of instrument panel, near steering column. PCM utilizes two 80-pin connectors. (Scheme 111), (Scheme 112) and (Scheme 113). PCM controls ignition, fuel and emission devices related to engine and transaxle upshifts and downshifts.

PCM receives electronic signals from sensors and switches. These signals help PCM determine when to operate various relays and solenoids related to engine and transaxle control.

SENSORS & SWITCHES

PCM controls upshifts and downshifts based on coolant temperature (or transaxle temperature), throttle position, Transaxle Range (TR) switch position, vehicle speed sensor and brake pedal switch. System includes several other switches and sensors which are used for engine control.

SOLENOIDS

Transaxle is shifted up or down by 2 electric solenoids. Both solenoids are located on valve body. Ignition power is supplied to each solenoid through a 10-amp fuse. For solenoid positions at each selector lever position, see SOLENOID POSITIONS table.

SOLENOID POSITIONS

PRESSURE CONTROL SOLENOID

Transmission Adaptive Pressure (TAP) values may need to be reset if one of the following repairs has been performed

1. Transaxle overhaul or replacement.
2. Repair or replacement of an apply or release component (band, clutch, piston and/or servo).
3. Repair or replacement of a component or assembly which directly affects line pressure.

To reset TAP values, see CLEARING & RESETTING TAP VALUES under DIAGNOSTIC & TESTING.

Pressure control (force motor) solenoid has a spool valve and operates pressure regulator valve. (Scheme 110) PCM sends a frequency signal to pressure control solenoid to regulate hydraulic line pressure. When duty cycle is zero, line pressure is at maximum, and pressure control solenoid draws zero amps. When duty cycle is 40 percent, line pressure is at minimum, and pressure control solenoid draws 1.1 amps at 4.5 volts.

TORQUE CONVERTER CLUTCH CONTROL COMPONENTS

The following component signals are used in TCC operation

Brake Switch

Power from ignition switch passes through brake switch to TCC solenoid. When brake pedal is depressed with TCC applied, power to TCC solenoid is interrupted, releasing converter clutch and preventing engine from stalling.

Engine Coolant Temperature Sensor

The Engine Coolant Temperature (ECT) sensor provides PCM with engine coolant temperature information. PCM will not allow TCC operation until signal from this sensor indicates coolant temperature more than 130-150°F (55-65°C).

Powertrain Control Module

To determine application of torque converter clutch, Powertrain Control Module (PCM) receives and processes information from various input devices. These devices may include vehicle speed sensor, engine coolant temperature sensor, throttle position sensor and brake switch. PCM controls application of torque converter clutch by providing a ground circuit for TCC solenoid circuit.

Torque Converter Clutch Solenoid

Torque Converter Clutch (TCC) solenoid is energized by PCM to redirect ATF to converter clutch apply valve in control valve assembly. TCC solenoid controls apply and release of TCC.

Throttle Position Sensor

Throttle Position (TP) sensor provides PCM with throttle position information. TCC operation is prevented when throttle position signal is less than a specified value.

Vehicle Speed Sensor

Vehicle Speed Sensor (VSS) sends vehicle speed information to PCM. Vehicle speed must be more than a certain value before TCC can be applied. VSS is a Permanent Magnet (PM) generator type sensor, and is mounted on transaxle.

Note. Diagnostic codes for engine coolant temperature sensor and throttle position sensor may be present while performing TCC electrical diagnosis. For complete diagnostic information for these DTCs, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

LIMP-IN MODE

If sensor input signals are missing or inadequate for transaxle operation, PCM will output preset operating signals to transaxle. Limp-in mode will keep vehicle operational and allow it to be driven with reduced transaxle function and performance, to a repair facility. Malfunction Indicator Light (MIL) will illuminate if malfunction occurs. Vehicle should not be driven for extended periods in limp-in mode.

PRELIMINARY INSPECTION

1. Check transaxle fluid level and condition. Inspect all wiring harnesses and connections leading to transaxle. Verify brake system is operational and not dragging.
2. Check all vacuum hoses for correct routing, restrictions, cuts or other damage. Inspect difficult-to-see vacuum hoses beneath air cleaner assembly and other engine components.
3. Inspect all engine compartment wiring for proper connections. See «WIRING DIAGRAMS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . Check wires for pinched or chafed spots, as well as contact with sharp edges or exhaust manifolds.
4. Repair any faults as necessary. If no faults are found during preliminary inspection, begin diagnosis of transaxle electronic control system. See «DIAGNOSIS & TESTING»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__diagnosis-testing) .

DIAGNOSIS & TESTING

Note. To test electronic control of transaxle solenoids without using self-diagnostics or if self-diagnostics does not function, go to CIRCUIT TESTS and COMPONENT TESTS . After repairs are made, DTCs should be cleared from computer memory. See CLEARING DIAGNOSTIC TROUBLE CODES .

Note. If no DTCs are present and vehicle is in limp-in mode, check fused power supply circuit to transaxle solenoids. Non-related transaxle component system failure may cause this circuit fuse to fail. Fuses such as ERLS or SHIFT SOL fuse supply power to non-related transaxle components (A/C clutch, EGR, EVAP, or ABS system) which may have caused fuse to fail.

Note. DTCs will be recorded at various operating times. Some DTCs require operation of affected sensor or switch for 5 seconds; others may need operation for 5 minutes or longer at normal operating temperature, road speed and load. Therefore, some DTCs may not set in a service bay operational mode and may need road testing vehicle in order to duplicate condition under which DTC will set.

ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK

Note. Check for applicable Technical Service Bulletins (TSBs) before proceeding. DO NOT perform the following procedure if driveability conditions are not present. DO NOT turn ignition off during the following procedure or clear DTCs unless instructed to do so.

Note. Use of scan tool is required to perform OBD system check. Perform this test prior to performing any diagnostic procedures in diagnostic tests. For scan tool data values, refer to scan tool manufacturer's instruction manual.

Note. Most problems that exist with the MIL or diagnostic system are engine performance or PCM related. Procedures for repairing these systems and circuits may need additional engine performance repair data. This test contains references to additional procedures not found in this publication.

The OBD system check determines

1. If Malfunction Indicator Light (MIL) works.
2. If PCM is operating and can recognize a fault.
3. If any DTCs are stored.

OBD system check is the starting point for utilizing the self-diagnostic system for determining computer-related problems. After performing necessary tests as described in OBD system check, if no DTCs are indicated and driveability problems still exist, see appropriate TROUBLE SHOOTING - NO CODES article in ENGINE PERFORMANCE.

Note. The following steps should be performed first to reduce diagnostic time and prevent replacement of good parts.

1. Connect scan tool to 16-pin Data Link Connector (DLC), located under left side of instrument panel. Turn ignition switch to ON position. If scan tool powers up, go to next step. If scan tool does not power up, see «NO DATA LINK CONNECTOR DATA»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__no-data-link-connector-data) under SYMPTOM TESTS.
2. Observe MIL. If MIL is illuminated, go to next step. If MIL is not illuminated, see «NO MALFUNCTION INDICATOR LIGHT»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__no-malfunction-indicator-light) under SYMPTOM TESTS.
3. Using scan tool, attempt to communicate with PCM. If scan tool communicates with PCM, go to next step. If scan tool does not communicate with PCM, see «NO DATA LINK CONNECTOR DATA»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__no-data-link-connector-data) under SYMPTOM TESTS.
4. Using scan tool, check for DTCs. Record freeze frame and failure records information. Identify DTCs. See «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__diagnostic-trouble-code-definitions) . After identification, diagnose DTCs. See «DIAGNOSTIC TESTS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . If no DTCs are stored, see appropriate TROUBLE SHOOTING - NO CODES article in ENGINE PERFORMANCE.

RETRIEVING DIAGNOSTIC TROUBLE CODES

Note. Stored DTCs may be retrieved from PCM memory using a scan tool. DTCs CANNOT be retrieved by grounding DLC. Plugging scan tool into DLC, located under instrument panel, enables user to read DTCs and check voltages in system on serial data line.

Scan tools may furnish information on status of output devices (solenoids and relays). However, status parameters are only an indication that output signals have been sent to devices by PCM; they do not indicate if devices have responded properly to signal. Check for proper response at output device using a DVOM or test light.

If DTCs are not present, this is not necessarily an indication a problem does not exist. Driveability related problems with DTCs displayed occur about 20 percent of the time, while driveability problems without DTCs occur about 80 percent of the time. Sensors that are out of specification WILL NOT set a DTC but WILL cause driveability problems. Using scan tool is the easiest method of checking sensor specifications and other data parameters. Scan tool is useful in finding intermittent wiring problems by wiggling wiring harness and connections (key on, engine off) while observing scan tool.

DIAGNOSTIC TROUBLE CODE DEFINITIONS

Note. Only transaxle-related DTCs are listed. See DIAGNOSTIC TROUBLE CODE DEFINITIONS table. For engine-related DTC definitions, see TROUBLE CODE DEFINITIONS article in GENERAL INFORMATION. For engine-related DTC diagnosis, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. These DTCs pertain to engine performance and must be repaired first, as engine performance and related component signals will affect transaxle operation and diagnosis.

There are 3 types of DTC categories

1. Type "A" Emissions related. Illuminates MIL the first time DTC sets.
2. Type "B" Emissions related. Illuminates MIL if fault is active for 2 consecutive driving cycles.
3. Type "C" Non-emissions related. Does not illuminate MIL, but will illuminate SERVICE light.

DIAGNOSTIC TROUBLE CODE DEFINITIONS

CLEARING DIAGNOSTIC TROUBLE CODES

DTCs can be cleared using scan tool. If scan tool is not available, turn ignition switch to OFF position. Remove PCM fuse from fuse block for 30 seconds. Replace fuse. DTCs may also be cleared by disconnecting negative battery cable. However, this may result in loss of other on-board memory data, such as preset radio tuning. After power to PCM is removed, poor driveability may occur until PCM "relearns" operating parameters.

DTCs will be cleared under the following conditions: PCM will cancel DTC default actions when fault no longer exists and ignition is cycled off long enough to power down PCM. DTC will be cleared when vehicle has achieved 40 warm-up cycles without failure reported.

HARD OR INTERMITTENT DIAGNOSTIC TROUBLE CODE DETERMINATION

During any diagnostic procedure, it must be determined if DTCs are hard failure DTCs or intermittent failure DTCs. Diagnostic tests usually will not help analyze intermittent failure DTCs. To determine hard failure DTCs and intermittent failure DTCs, proceed as follows

1. Enter diagnostic mode. See «RETRIEVING DIAGNOSTIC TROUBLE CODES»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__retrieving-diagnostic-trouble-codes) . Read and record all stored DTCs. Exit diagnostic mode and clear DTCs. See «CLEARING DIAGNOSTIC TROUBLE CODES»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__clearing-diagnostic-trouble-codes) .
2. Apply parking brake and place transaxle in Neutral or Park. Block drive wheels and start engine. MIL should go out. Run warm engine at specified curb idle for 2 minutes and note MIL.
3. If MIL illuminates, enter diagnostic mode. Read and record DTCs. DTCs may need a road test to reset hard failure after clearing DTCs. If MIL does not come on, all stored DTCs were intermittent failure codes.

CLEARING & RESETTING TAP VALUES

Using scan tool, clear and reset TAP values. Follow scan tool manufacturer's instructions. Start engine and allow to reach normal operating temperature with transaxle in Park. Ensure all accessories are off. Apply brakes and shift transaxle into Drive. Allow engine to idle for 2 minutes. Perform road test for 5-7 miles. Operate vehicle under normal conditions. Avoid extreme acceleration. Once road test is complete, allow engine to return to idle. Place transaxle in PARK. Allow engine to idle for 1 minute. Turn engine off.

CONNECTOR IDENTIFICATION

Note. For connector identification and component locations, refer to illustrations. (Scheme 109)- (Scheme 113).

Scheme 109

Scheme 110

Scheme 111

Scheme 112

Scheme 113

Diagnostic Procedures

The following diagnostic procedures are DTC specific. Perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK under DIAGNOSIS & TESTING prior to performing any diagnostic procedure. For PCM terminal identification (Scheme 111), (Scheme 112) and (Scheme 113). See WIRING DIAGRAMS. For engine-related DTCs, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

Diagnostic Aids

Diagnostic aids, located at end of each diagnostic test, are additional tips used to help diagnose DTCs when diagnostic procedures do not find a fault.

Circuit Description

Body Control Module (BCM) controls shift lock control solenoid. Voltage is supplied through fused circuit to terminal "B" of shift lock control solenoid. BCM supplies a ground signal to solenoid through terminal "A" of solenoid. When brake pedal is depressed, BCM removes ground signal allowing solenoid to disengage. This action allows vehicle to be shifted out of park.

Conditions For Running DTC B2707

1. Ignition is on.
2. Brake pedal is depressed.

Conditions For Setting DTC B2707

Shift lock control circuit is open or shorted to ground for 5 seconds.

Action Taken When DTC Sets

1. If shift lock control circuit is open, shift lock solenoid will be inoperative.
2. If shift lock control circuit is shorted to ground, shift lock solenoid will be stuck in engaged position.

Diagnostic Procedure

Note. For connector terminal locations and wiring diagrams, see appropriate GENERAL MOTORS SHIFT INTERLOCK SYSTEMS article.

1. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, command shift lock solenoid on and off. If shift lock solenoid turns on and off when commanded, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . If shift lock solenoid does not turn on and off when commanded, go to next step.
2. Turn ignition off. Disconnect shift lock solenoid harness connector. Solenoid is located at shifter mechanism. Turn ignition switch to ON position. Using test light connected to ground, probe coil side feed circuit of shift lock solenoid. If test light illuminates, go to next step. If test light does not illuminate, go to step 9 .
3. Connect test light between control circuit of shift lock solenoid and coil side feed circuit of shift lock solenoid. Using scan tool, command shift lock solenoid on and off. If test light turns on and off with each command, go to step 7 . If test light does not turn on and off with each command, go to next step.
4. If test light remains illuminated with each command, go to step 6 . If test light remains off with each command, go to next step.
5. Check for open in shift lock solenoid control circuit. Repair as necessary. After repairs, go to step 12 . If shift lock solenoid control circuit is okay, go to step 8 .
6. Check for short to ground in shift lock solenoid control circuit. Repair as necessary. After repairs, go to step 12 . If shift lock solenoid control circuit is okay, go to step 8 .
7. Check for poor connections at shift lock solenoid. Repair as necessary. After repairs, go to step 12 . If connections at shift control solenoid are okay, go to step 10 .
8. Check for poor connections at BCM harness connector. Repair as necessary. After repairs, go to step 12 . If harness connectors are okay, go to step 11 .
9. Repair coil side feed circuit of shift lock solenoid. After repairs, go to step 12 .
10. Replace shift lock solenoid. After repairs, go to step 12 .
11. Replace BCM. After repairs, go to next step.
12. Using scan tool, clear DTCs. Operate vehicle within conditions for running DTC. If DTC does not reset, repair is complete. If DTC resets, go to step 1 .

Perform tests while wiggling wires and connectors. This may often cause an intermittent malfunction to appear.

Body Control Module (BCM) controls shift lock control solenoid. Positive voltage is supplied through fused circuit to terminal "B" of shift lock control solenoid. BCM supplies a ground signal to solenoid through terminal "A" of solenoid. When brake pedal is depressed, BCM removes ground signal allowing solenoid to disengage. This action allows vehicle to be shifted out of park.

Conditions For Running DTC B2708

1. Ignition is on.
2. Brake pedal is depressed.

Conditions For Setting DTC B2708

Shift lock control circuit is shorted to battery voltage for one second.

BCM disables shift lock control output for remainder of ignition cycle.

Note. For connector terminal locations and wiring diagrams, see appropriate GENERAL MOTORS SHIFT INTERLOCK SYSTEMS article.

1. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, command shift lock solenoid on and off. If shift lock solenoid turns on and off when commanded, go to «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . If shift lock solenoid does not turn on and off when commanded, go to next step.
2. Turn ignition off. Disconnect shift lock solenoid harness connector. Solenoid is located at shifter mechanism. Turn ignition switch to ON position. Using test light connected to ground, probe coil side feed circuit of shift lock solenoid. If test light illuminates, go to next step. If test light does not illuminate, go to step 9 .
3. Connect test light between control circuit of shift lock solenoid and coil side feed circuit of shift lock solenoid. Using scan tool, command shift lock solenoid on and off. If test light turns on and off with each command, go to step 7 . If test light does not turn on and off with each command, go to next step.
4. If test light remains illuminated with each command, go to step 6 . If test light remains off with each command, go to next step.
5. Check for short to voltage in shift lock solenoid control circuit. Repair as necessary. After repairs, go to step 12 . If shift lock control solenoid circuit is okay, go to step 8 .
6. Check for short to ground in shift lock solenoid control circuit. Repair as necessary. After repairs, go to step 12 . If shift lock solenoid control circuit is okay, go to step 8 .
7. Check for poor connections at shift lock solenoid. Repair as necessary. After repairs, go to step 12 . If connections at shift control solenoid are okay, go to step 10 .
8. Check for poor connections at BCM harness connector. Repair as necessary. After repairs, go to step 12 . If harness connectors are okay, go to step 11 .
9. Repair coil side feed circuit of shift lock solenoid. After repairs, go to step 12 .
10. Replace shift lock solenoid. After repairs, go to step 12 .
11. Replace BCM. After repairs, go to next step.
12. Using scan tool, clear DTCs. Operate vehicle within conditions for running DTC. If DTC does not reset, repair is complete. If DTC resets, go to step 1 .

Perform tests while wiggling wires and connectors. This may often cause an intermittent malfunction to appear.

Transaxle oil pump is constantly circulating fluid through torque converter. Hot fluid leaving converter flows through transaxle cooler lines to oil cooler, located in radiator. Fluid is then routed back to transaxle.

Lube circuit No. 1 is routed through input shaft to lubricate transaxle components in front of transaxle. Lube circuit No. 2 is fed by line pressure at pressure regulator valve. This fluid is routed through oil feed pipes and into forward clutch support. Lube circuit No. 2 provides lubrication to rear of transaxle. DTC P0218 will set when PCM detects a high transaxle fluid temperature for long period of time.

Conditions For Running DTC P0218

DTCs P0711, P0712 or P0713 (transaxle fluid temperature sensor) are not present.

Conditions For Setting DTC P0218

Transaxle temperature is more than 260°F (130°C) for 10 minutes.

Action Taken By PCM

PCM performs the following if DTC is set

1. Will not illuminate MIL when fault is set.
2. Freezes shift adapts from being updated.
3. DTC P0218 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record failure records for reference. Clear DTC. Ensure transaxle fluid level is correct. Fill if necessary. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. If transaxle fluid level is okay, go to next step.
3. Inspect engine and transaxle cooling system for air flow restrictions or blockage, debris or damaged cooler lines. Repair as necessary, then go to step 5 . If no problems are found, go to next step.
4. Check control valve assembly for stuck or leaking pressure regulator valve. Repair as necessary, then go to next step. If control valve assembly is okay, inspect oil feed tubes for restriction or leaking seals. Repair as necessary, then go to next step. If tubes are okay, check for torque converter stator damage. Repair as necessary, then go to next step.
5. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0218". Turn ignition switch to ON position for 10 seconds. TFT temperature must be 264°F (129°C) or less for 5 seconds. If DTC P0218 is not present, repair is complete. If DTC P0218 is still present, repeat test.

Question owner for possible vehicle overloading, exceeding trailer towing limit or towing in overdrive.

Vehicle speed is signaled to PCM by Vehicle Speed Sensor (VSS). Sensor is a Permanent Magnet (PM) generator mounted to transaxle case. PM generator produces an AC voltage as speed sensor rotor teeth pass sensor's magnetic field. AC voltage level increases as speed of vehicle increases. PCM converts AC voltage into digital signal. PCM uses vehicle speed to determine shift timing, TCC apply and release, and gear ratio calculations. DTC P0502 will set when PCM detects a low vehicle output speed when vehicle has high engine speed in drive gear.

Conditions For Running DTC P0502

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0716, P0717 (input speed sensor), P1644 or P1810 (pressure switch assembly) are not present.
2. Transaxle is in a drive range.
3. TP angle is more than 12 percent.
4. MAP is more than 7.3 psi (50 kPa) on 2.2L and 2.4L.
5. Input speed is more than 2000 RPM on 2.2L and 2.4L or more than 1500 RPM on 3.1L and 3.4L.
6. Engine torque is more than 25 Ft. Lbs. (34 N.m).
7. Output speed is less than 2 MPH on 2.2L and 2.4L or less than 150 RPM for 3 seconds on 3.1L and 3.4L.

Conditions For Setting DTC P0502

Output speed is less than 150 RPM for 3 seconds.

PCM performs the following if DTC is set

1. Will light MIL after 2 consecutive trips with a failure signal.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. Calculates output speed from input speed, engine speed and commanded gear.
5. DTC P0502 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Raise and support vehicle. Start engine and let it idle. Shift selector lever to "D" position. With drive wheels rotating, if transaxle output speed does not increase when wheel speed increases, go to next step. If transaxle output speed increases when wheel speed increases, condition is intermittent. See «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
3. Turn ignition off. Disconnect PCM connectors. Connect DVOM set to AC volts between VSS signal circuit and VSS ground circuit terminals at appropriate PCM connector. Turn ignition switch to ON position. Rotate right front drive wheel by hand, and observe DVOM. If voltage is more than .5 volts, go to step 14 . If voltage is .5 volts or less, go to next step.
4. Turn ignition off. Set DVOM to ohms while still connected to VSS terminals at PCM connectors. If resistance is 1530-1870 ohms, go to step 8 . If resistance is not 1530-1870 ohms, go to next step.
5. If resistance is more than 1870 ohms, go to step 11 . If resistance is less than 1870 ohms, go to next step.
6. Leave DVOM test leads connected to appropriate PCM connector. Disconnect VSS connector at transaxle. If resistance is less than 1530 ohms, go to next step. If resistance is more than 1530 ohms, go to step 13 .
7. Check for shorted together signal and ground circuits between PCM and VSS. Repair as necessary. After repairs, go to step 15 .
8. Check for short to ground in signal circuit between PCM and VSS. Repair as necessary. After repairs, go to step 15 . If signal circuit is okay, go to next step.
9. Reconnect PCM connectors. Set DVOM to DC volts. Connect DVOM to VSS connector terminals. Turn ignition switch to ON position. If DVOM displays system voltage, go to next step. If DVOM does not display system voltage, go to step 12 .
10. Check for short to voltage in VSS signal circuit between PCM and VSS. Repair as necessary. After repairs go to step 15 .
11. Check for open in VSS signal and ground circuits between PCM and VSS. Repair as necessary. After repairs, go to step 15 . If VSS signal and ground circuits are okay, go to step 13 .
12. Check for incorrect speed sensor, sensor damage, excessive air gap between sensor and rotor, rotor damage or incorrect rotor alignment. Inspect for transaxle case damage. Repair or replace components as necessary. After repairs, go to step 15 .
13. Replace VSS. After repairs, go to step 15 .
14. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
15. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0502". Operate vehicle at more than 2 MPH for 5 seconds. If DTC P0502 is not present, repair is complete. If DTC P0502 is still present, repeat test.

Condition may be intermittent. Check for loose speed sensor mounting or poor sensor connection. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change. Inspect for damaged speed sensor or transaxle rotor teeth. A slipping forward clutch could set DTC P0502.

Vehicle speed is signaled to PCM by Vehicle Speed Sensor (VSS). Sensor is a Permanent Magnet (PM) generator mounted to transaxle case. PM generator produces an AC voltage as speed sensor rotor teeth pass sensor's magnetic field. AC voltage level increases as speed of vehicle increases. PCM converts AC voltage into digital signal. PCM uses vehicle speed to determine shift timing, TCC apply and release, and gear ratio calculations. DTC P0503 will set when PCM detects a loss of vehicle speed while vehicle is in motion.

Conditions For Running DTC P0503

1. DTC P1810 (pressure switch assembly) is not present.
2. Time since selector lever change is more than 6 seconds.
3. An increase in output speed of 500 RPM or more has not occurred for more than 5 seconds.

Conditions For Setting DTC P0503

Output speed drops more than 1200 RPM for 3 seconds.

PCM performs the following if DTC is set

1. Will light MIL after 2 consecutive trips with a failure signal.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. Calculates output speed from input speed, engine speed and commanded gear.
5. DTC P0503 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Raise and support vehicle. Start engine and let it idle. Shift selector lever to "D" position. With drive wheels rotating, if transaxle output speed does not increase when wheel speed increases, go to next step. If transaxle output speed increases when wheel speed increases, condition is intermittent. See «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
3. Turn ignition off. Disconnect PCM connectors. Connect DVOM set to AC volts between VSS signal circuit and VSS ground circuit terminals at appropriate PCM connector. Turn ignition switch to ON position. Rotate right front drive wheel by hand, and observe DVOM. If voltage is more than .5 volts, go to step 14 . If voltage is .5 volts or less, go to next step.
4. Turn ignition off. Set DVOM to ohms while still connected to VSS circuits at PCM connectors. If resistance is 1530-1870 ohms, go to step 8 . If resistance is not 1530-1870 ohms, go to next step.
5. If resistance is more than 1870 ohms, go to step 11 . If resistance is less than 1870 ohms, go to next step.
6. Leave DVOM test leads connected to appropriate PCM connector. Disconnect VSS connector at transaxle. If resistance is less than 1530 ohms, go to next step. If resistance is more than 1530 ohms, go to step 13 .
7. Check for shorted together signal and ground circuits between PCM and VSS. Repair as necessary. After repairs, go to step 15 .
8. Check for short to ground in signal circuit between PCM and VSS. Repair as necessary. After repairs, go to step 15 . If signal circuit is okay, go to next step.
9. Reconnect PCM connectors. Set DVOM to DC volts. Connect DVOM to VSS connector terminals. Turn ignition switch to ON position. DO NOT start engine. If DVOM displays system voltage, go to next step. If DVOM does not display system voltage, go to step 12 .
10. Check for short to voltage in VSS signal circuit between PCM and VSS. Repair as necessary. After repairs, go to step 15 .
11. Check for open in VSS signal and ground circuits between PCM and VSS. Repair as necessary. After repairs, go to step 15 . If VSS signal and ground circuits are okay, go to step 13 .
12. Check for incorrect speed sensor, sensor damage, excessive air gap between sensor and rotor, rotor damage or incorrect rotor alignment. Inspect for transaxle case damage. Repair or replace components as necessary. After repairs, go to step 15 .
13. Replace VSS. After repairs, go to step 15 .
14. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
15. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0503". Road test vehicle and ensure speed sensor is operating. If DTC P0503 is not present, repair is complete. If DTC P0503 is still present, repeat test.

Condition may be intermittent. Check for loose speed sensor mounting or poor sensor connection. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change. Inspect for damaged speed sensor or transaxle rotor teeth.

Transmission Fluid Temperature (TFT) sensor is a negative coefficient thermistor. When fluid temperature is cold, sensor resistance is high. As ATF warms, sensor resistance decreases. PCM monitors TFT sensor circuit. Circuit may be functional but not in normal operating range. DTC P0711 indicates stuck, erratic, intermittent or skewed values, indicating poor system performance. TFT range is -40 to 305°F (-40 to 151°C). DTC P0711 will set when PCM detects an intermittent voltage or no voltage change in TFT sensor circuit.

Conditions For Running DTC P0711

1. DTCs P0502, P0503 (vehicle speed sensor), P0716 or P0717 (input speed sensor) are not present.
2. System voltage is 8-18 volts.
3. Engine run time is more than 5 minutes.
4. Engine coolant temperature is more than 158°F (70°C).
5. Engine coolant temperature has changed by more than 90°F (50°C) since start-up.
6. Transmission fluid temperature at start-up is -40 to 70°F (-40 to 21°C).
7. Vehicle speed is more than 5 MPH for 6 minutes and 49 seconds.
8. TCC slip is more than 300 RPM for 6 minutes and 49 seconds.

Conditions For Setting DTC P0711

Change in transaxle fluid temperature is less than 2°F (1.5°C) since start-up for one minute and 20 seconds, or change in transaxle fluid temperature is more than 36°F (20°C) within 200 milliseconds, 14 times within 7 seconds.

PCM performs the following if DTC is set

1. Will not light MIL when fault is set.
2. Freezes shift adapts from being updated.
3. Will calculate default transaxle temperature based on engine coolant temperature, manifold air temperature and engine run time.
4. DTC P0711 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Check transaxle fluid level. Fill if necessary. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
3. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Select "TFT sensor" on scan tool. Drive vehicle and observe scan tool for one of the following fail conditions: TFT sensor fluid temperature does not change by more than 2.7°F (1.5°C) in 20 seconds since start-up, or TFT sensor fluid temperature changes by more than 36°F (20°C) within 200 milliseconds, 14 times within 7 seconds (unrealistic change). If either fail condition occurs, go to next step. If neither fail conditions occurs, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
4. If scan tool displays a condition in which TFT sensor fluid temperature does not change by more than 2.7°F (1.5°C) in 20 seconds since start-up, go to step 6 . If scan tool does not display this condition, go to next step.
5. Turn ignition off. Disconnect transaxle 20-pin connector. Install Jumper Harness (J-39775) on engine side of transaxle 20-pin connector. Connect a test light between terminals "L" and "M" at transaxle 20-pin connector. Turn ignition switch to ON position. While observing scan tool display, wiggle wiring harness between transaxle 20-pin connector and PCM connectors. If TFT sensor fluid temperature changes by more than 36°F (20°C), go to step 7 . If TFT sensor fluid temperature does not change by more than 36°F (20°C), go to step 8 .
6. Turn ignition off. Disconnect transaxle 20-pin connector. Turn ignition switch to ON position. If scan tool displays a condition in which TFT sensor fluid temperature does not change by more than 2.7°F (1.5°C) in 20 seconds since start-up, go to step 11 . If scan tool does not display this condition, go to step 10 .
7. Check for intermittent open or short in TFT sensor signal and ground circuits between PCM and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 12 . If TFT sensor signal and ground circuits are okay, go to step 11 .
8. Check for intermittent open or short in TFT sensor signal and ground circuits between transaxle 20-pin connector and TFP manual valve position switch. If open or short is found in TFT sensor signal or ground circuits, go to next step. If TFT sensor signal and ground circuits are okay, go to step 10 .
9. Replace internal transaxle wire harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 12 .
10. Replace TFP manual valve position switch. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 12 .
11. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
12. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0711". Drive vehicle and ensure TFT sensor fluid temperature changes by more than 4°F (2.25°C) for 5 seconds since start-up, and TFT sensor fluid temperature does not change by more than 36°F (20°C) within 200 milliseconds for at least 11 seconds. If DTC P0711 is not present, repair is complete. If DTC P0711 is still present, repeat test.

Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. Test TFT sensor at various temperature levels to evaluate possibility of a skewed (mis-scaled) sensor. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change. Inspect transaxle wiring harness for ATF.

Transmission Fluid Temperature (TFT) sensor is a thermistor. TFT sensor is part of Transmission Fluid Pressure (TFP) manual valve position switch. PCM supplies a 5-volt reference signal to sensor. When transaxle fluid is cold, sensor resistance is high and PCM senses a high signal voltage. As transaxle fluid warms, sensor resistance lowers and PCM senses lower voltage. PCM uses TFT reading in order to control TCC apply & release, line pressure adjustments, and temperature compensated shifts. DTC P0712 will set when PCM detects a continuous short to ground in TFT circuit or TFT sensor.

Conditions For Running DTC P0712

1. Ignition is on.
2. System voltage is 8-18 volts.

Conditions For Setting DTC P0712

TFT sensor voltage is less than .33 volt for 10 seconds.

PCM performs the following if DTC is set

1. Will not light MIL when fault is set.
2. Freezes shift adapts from being updated.
3. Will calculate transaxle temperature based on engine coolant temperature, manifold air temperature and engine run time.
4. DTC P0712 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Select "TFT sensor" on scan tool. If scan tool displays transaxle fluid temperature voltage of less than .33 volts, go to next step. If scan tool does not display transaxle fluid temperature voltage of less than .33 volts, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
3. Turn ignition off. Disconnect transaxle 20-pin connector. Turn ignition switch to ON position. If scan tool displays transaxle fluid temperature voltage of more than 4.92 volts, go to step 5 . If scan tool does not display transaxle fluid temperature voltage of more than 4.92 volts, go to next step.
4. Check for short to ground in TFT sensor signal circuit between PCM and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 11 . If TFT sensor signal circuit is okay, go to step 10 .
5. Turn ignition off. Install Jumper Harness (J-39775) to transaxle side of transaxle 20-pin connector. Measure resistance between terminals "L" and "M" at jumper harness. If resistance is 3106-3923 ohms at 68°F (20°C) and 164-190 ohms at 212°F (100°C), go to next step. If resistance is not 3106-3923 ohms at 68°F (20°C) and 164-190 ohms at 212°F (100°C), go to step 7 .
6. Measure resistance between terminal "L" of jumper harness and a good ground. If resistance is less than 1000 ohms, go to step 9 . If resistance is 1000 ohms or more, go to «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
7. Disconnect TFP manual valve position switch from transaxle wiring harness. Measure resistance between terminals "L" and "M" of jumper harness. If resistance is 1000 ohms or less, go to step 9 . If resistance is more than 1000 ohms, go to next step.
8. Replace TFP manual valve position switch. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
9. Replace internal transaxle wire harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
10. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
11. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0712". Turn ignition switch to ON position. TFT sensor signal voltage must be more than .33 volts for 10 seconds. If DTC P0712 is not present, repair is complete. If DTC P0712 is still present, repeat test.

Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

Transmission Fluid Temperature (TFT) sensor is a thermistor. TFT sensor is part of Transmission Fluid Pressure (TFP) manual valve position switch. PCM supplies a 5-volt reference signal to sensor. When transaxle fluid is cold, sensor resistance is high and PCM senses a high signal voltage. As transaxle fluid warms, sensor resistance lowers and PCM senses lower voltage. PCM uses TFT reading in order to control TCC apply and release, line pressure adjustments, and temperature compensated shifts. DTC P0713 will set when PCM detects a continuous open or short to voltage in TFT sensor circuit or TFT sensor.

Conditions For Running DTC P0713

1. Ignition is on.
2. System voltage is 8-18 volts.

Conditions For Setting DTC P0713

TFT sensor voltage is more than 4.9 volts for 6 minutes 40 seconds.

PCM performs the following if DTC is set

1. Will not light MIL when fault is set.
2. Freezes shift adapts from being updated.
3. Will calculate transaxle temperature based on engine coolant temperature, manifold air temperature and engine run time.
4. DTC P0713 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Select "TFT sensor" on scan tool. If scan tool displays transaxle fluid temperature voltage of more than 4.9 volts, go to next step. If scan tool does not display transaxle fluid temperature voltage of more than 4.92 volts, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
3. Turn ignition off. Disconnect transaxle 20-pin connector. Install Jumper Harness (J-39775) to PCM side of transaxle 20-pin connector. Connect fused jumper between jumper harness terminals "L" and "M". Turn ignition switch to ON position. If scan tool displays transaxle fluid temperature voltage of less than .33 volts, go to step 7 . If scan tool displays transaxle fluid temperature voltage of .33 volts or more, go to next step.
4. Connect jumper wire between terminal "L" and ground on PCM side of transaxle 20-pin connector. If scan tool displays transaxle fluid temperature voltage of less than .33 volts, go to step 6 . If scan tool displays transaxle fluid temperature voltage of .33 volts or more, go to next step.
5. Check for open in TFT sensor signal circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 11 . If TFT sensor signal circuit is okay, go to step 10 .
6. Check for open in TFT sensor ground circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 11 .
7. Check for open in TFT sensor signal and ground circuits between TFP manual valve position switch and transaxle 20-pin connector. If open is found in TFT sensor signal or ground circuits, go to next step. If TFT sensor signal and ground circuits are okay, go to step 9 .
8. Replace internal transaxle wire harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
9. Replace TFP manual valve position switch. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
10. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
11. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0713". Turn ignition switch to ON position. TFT sensor signal voltage must be less than 4.9 volts for one minute. If DTC P0713 is not present, repair is complete. If DTC P0713 is still present, repeat test.

Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

Transaxle input speed is signaled to PCM by Input Speed Sensor (ISS). Sensor is a Permanent Magnet (PM) generator. Sensor mounts into transaxle case and maintains slight air gap between sensor and drive sprocket. PM generator produces an AC voltage as drive sprocket rotor teeth pass in front of sensor's magnetic field. AC voltage level increases as speed of turbine shaft increases. PCM converts AC voltage into digital signal. This signal is then used by PCM to determine actual turbine shaft speed. PCM uses input speed to calculate torque converter slip speed and gear ratios. DTC P0716 will set when PCM detects an unrealistic change in input speed.

Conditions For Running DTC P0716

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0502, P0503 (vehicle speed sensor), P0717, P0751, P0753 or P0758 are not present.
2. Engine is running.
3. Throttle position angle is more than 15 percent.
4. Vehicle speed is more than 5 MPH.

Conditions For Setting DTC P0716

Input speed change is more than 1300 RPM in .8 seconds.

PCM performs the following if DTC is set

1. Will light MIL after 2 consecutive trips with a failure reported.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. DTC P0716 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Start engine. Observe ISS display. If input speed is more than 500 RPM, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . If input speed is 500 RPM or less, go to next step.
3. Turn ignition off. Disconnect transaxle 20-pin connector. Install Jumper Harness (J-39775) to transaxle side of transaxle 20-pin connector. Connect DVOM between terminals "S" and "V" of jumper harness. If resistance is 615-835 ohms, go to step 6 . If resistance is not 615-835 ohms, go to next step.
4. Check for open or short to ground in ISS signal circuit between transaxle 20-pin connector and ISS. If short or open is found in ISS signal circuit, go to step 8 . If ISS signal circuit is okay, go to next step.
5. Check for open in ISS ground circuit between transaxle 20-pin connector and ISS. If open is found in ISS ground circuit, go to step 8 . If ISS ground circuit is okay, go to step 9 .
6. Check for open or short to ground in ISS signal circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 11 . If ISS signal circuit is okay, go to next step.
7. Check for open in ISS ground circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 11 . If ISS ground circuit is okay, go to step 10 .
8. Replace internal transaxle wire harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
9. Replace input speed sensor. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
10. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
11. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0716". Shift transaxle to Park and start engine. Transaxle input speed must be more than 50 RPM for .3 seconds without a speed change of more than 300 RPM. If DTC P0716 is not present, repair is complete. If DTC P0716 is still present, repeat test.

Diagnostic test checks for input speed sensor circuit fault. If engine is running and vehicle is moving above 7 MPH, input speed must be more than zero. Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

Transaxle input speed is signaled to PCM by Input Speed Sensor (ISS). Sensor is a Permanent Magnet (PM) generator. Sensor mounts into transaxle case and maintains slight air gap between sensor and drive sprocket. PM generator produces an AC voltage as drive sprocket rotor teeth pass in front of sensor's magnetic field. AC voltage level increases as speed of turbine shaft increases. PCM converts AC voltage into digital signal. This signal is then used by PCM to determine actual turbine shaft speed. PCM uses input speed to calculate torque converter slip speed and gear ratios. DTC P0717 will set when PCM detects a low input speed when high vehicle speed exists.

Conditions For Running DTC P0717

1. DTCs P0502, P0503 (vehicle speed sensor) or P1810 (pressure switch assembly) are not present.
2. Engine is running.
3. Pressure switch assembly indicates transaxle is not in Park or Neutral.
4. Vehicle speed is more than 5 MPH.

Conditions For Setting DTC P0717

Input speed is less than 100 RPM for 5 seconds.

PCM performs the following if DTC is set

1. Will light MIL after 2 consecutive trips with failure reported.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. DTC P0717 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Start engine. Observe ISS display. If input speed is more than 500 RPM, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . If input speed is less than 500 RPM, go to next step.
3. Turn ignition off. Disconnect transaxle 20-pin connector. Install Jumper Harness (J-39775) to transaxle side of transaxle 20-pin connector. Measure resistance between terminals "S" and "V" of jumper harness. If resistance is 615-835 ohms, go to step 6 . If resistance is not 615-835 ohms, go to next step.
4. Check for open or short to ground in ISS signal circuit between transaxle 20-pin connector and ISS. If short or open is found in ISS signal circuit, go to step 8 . If ISS signal circuit is okay, go to next step.
5. Check for open in ISS ground circuit between transaxle 20-pin connector and ISS. If open is found in ISS ground circuit, go to step 8 . If ISS ground circuit is okay, go to step 9 .
6. Check for open or short to ground in ISS signal circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 11 . If ISS signal circuit is okay, go to next step.
7. Check for open in ISS ground circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 11 . If ISS ground circuit is okay, go to step 10 .
8. Replace internal transaxle wire harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
9. Replace input speed sensor. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
10. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
11. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0717". Shift transaxle into Park and start engine. Transaxle input speed must be more than 120 RPM for 3 seconds. If DTC P0717 is not present, repair is complete. If DTC P0717 is still present, repeat test.

Diagnostic test checks for input speed sensor circuit problem. If engine is running and vehicle is moving above 7 MPH, input speed must be more than zero. Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

The brake switch is used to indicate brake pedal status to PCM. Normally-closed brake switch supplies battery voltage to PCM. When brake pedal is applied, brake switch opens, interrupting voltage to PCM. When brake pedal is released, voltage is constant to PCM. When PCM sees zero volts at brake switch input, PCM de-energizes TCC solenoid. DTC P0719 will set when PCM detects an open (stuck on) brake switch during acceleration.

Conditions For Running DTC P0719

1. Ignition is on.
2. System voltage is 8-18 volts.

Conditions For Setting DTC P0719

DTC will set under the following conditions

1. Ignition is on.
2. PCM detects an open brake switch circuit (zero volts) for 15 minutes and following conditions occur 8 consecutive times.
3. Vehicle speed is less than 5 MPH, then vehicle speed is between 5-20 MPH for 3 seconds, then vehicle speed is more than 20 MPH for 6 seconds.

PCM performs the following if DTC is set

1. Will not light MIL when fault is set.
2. DTC P0719 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Disconnect brake switch connector. Connect fused jumper between brake switch connector terminals. Observe brake switch status on scan tool. If brake switch status changes from open to closed, go to step 5 . If brake switch status does not change from open to closed, go to next step.
3. Inspect appropriate fuse for brake switch power feed circuit. If fuse is open, go to next step. If fuse is okay, go to step 6 .
4. Check for short to ground in brake switch power feed circuit. Repair as necessary. After repairs, go to step 9 .
5. Inspect brake switch for proper adjustment. Adjust brake switch as necessary. If brake switch required adjustment, go to step 9 . If brake switch did not require adjustment, go to step 7 .
6. Check for open in brake switch power feed and input circuits. Repair as necessary. After repairs, go to step 9 . If brake switch power feed and input circuits are okay, go to step 8 .
7. Replace brake switch. After repairs, go to step 9 .
8. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
9. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0719". Turn ignition switch to ON position. DO NOT apply brake pedal. PCM must receive 12 volts (brake switch closed) on circuit for 3 seconds or more. If DTC P0719 is not present, repair is complete. If DTC P0719 is still present, repeat test.

Ask customer about driving habits and/or unusual traffic conditions such as heavy stop and go driving. Check brake switch for proper adjustment. Inspect wiring for poor connections at PCM and at brake switch connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

The brake switch is used to indicate brake pedal status to PCM. Normally-closed brake switch supplies battery voltage to PCM. When brake pedal is applied, brake switch opens, interrupting voltage to PCM. When brake pedal is released, voltage is constant to PCM. When PCM sees zero volts at brake switch input, PCM de-energizes TCC Pulse Width Modulated (PWM) solenoid. DTC P0724 will set when PCM detects a closed (stuck off) brake switch during deceleration.

Conditions For Running DTC P0724

1. Ignition is on.
2. System voltage is 8-18 volts.

Conditions For Setting DTC P0724

DTC will set under the following conditions

1. PCM detects a closed brake switch circuit (12 volts) during deceleration and following conditions occur 8 consecutive times.
2. Vehicle speed is more than 20 MPH for 6 seconds, then vehicle speed is between 5-20 MPH for 3 seconds, then vehicle speed is less than 5 MPH.

PCM performs the following if DTC is set

1. Will not light MIL when fault is set.
2. DTC P0724 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Disconnect brake switch connector. Observe brake switch status on scan tool. If brake switch status changes from closed to open, go to step 4 . If brake switch status does not change from closed to open, go to next step.
3. Check for short to voltage in brake switch input circuit. Repair as necessary. After repairs, go to step 6 . If brake switch input circuit is okay, go to step 5 .
4. Replace brake switch. After repairs, go to step 6 .
5. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
6. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0724". Turn ignition switch to ON position. Apply brake pedal for 3 seconds or more. If DTC P0724 is not present, repair is complete. If DTC P0724 is still present, repeat test.

Ask customer about driving habits and/or unusual traffic conditions such as heavy stop and go driving. Check brake switch for proper adjustment. Inspect wiring for poor connections at PCM and at brake switch connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

PCM calculates gear ratio based on transaxle input and output speed sensor readings. PCM compares known transaxle gear ratio to calculated ratio for particular gear range selected. DTC P0730 will set when PCM detects an unknown transaxle gear ratio.

Conditions For Running DTC P0730

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0502, P0503 (vehicle speed sensor), P0716, P0717 (input speed sensor) or P1810 (pressure switch assembly) are not present.
2. Engine is running.
3. Transmission Fluid Pressure (TFP) manual valve position switch in not in Park or Neutral.
4. Vehicle speed is more than 5 MPH.
5. Throttle position angle is more than 15 percent.
6. Transmission fluid temperature is more than 70°F (21°C).

Conditions For Setting DTC P0730

DTC will set under the following conditions

1. Engine torque is more than 18 ft. lbs. (25 N.m) on 3.1L and 3.4L models.
2. 6 seconds has passed since last manual shift change.

One of the following conditions occur for 7 seconds

1. Gear ratio is more than 3.13:1.
2. Gear ratio is 2.23:1-2.87:1.
3. Gear ratio is 1.71:1-2.02:1.
4. Gear ratio is 1.07:1-1.54:1.
5. Gear ratio is .72:1-.91:1.
6. Gear ratio is less than .61:1.

PCM performs the following if DTC is set

1. Will not light MIL when fault is set.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. DTC P0730 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Visually inspect transaxle cooling system for fluid leaks. Repair as necessary, then go to step 8 . If no leaks are found, go to next step.
3. Check transaxle fluid. Fill if necessary. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
4. Select snapshot mode on scan tool to record transaxle gear ratios. Drive vehicle in 1st, 2nd, 3rd and "D" position with throttle position angle more than 15 percent and vehicle speed more than 5 MPH. Record each gear ratio. Gear ratios should be 2.02-2.23 in Reverse, 2.87-3.13 in 1st gear, 1.54-1.71 in 2nd gear, .91-1.07 in 3rd gear and .61-.72 in "D". If gear ratios are not as specified, go to next step. If gear ratios are as specified, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
5. Perform line pressure test. See HYDRAULIC PRESSURE TESTS under PERFORMANCE TESTS in HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article.
6. Check for excessive clutch wear and repair as necessary. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article.
7. Change transaxle fluid and filter. Inspect transaxle fluid for correct level. Add new fluid as necessary. Use scan tool to perform clear TAPS function.
8. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0730". Drive vehicle in "D" position with throttle position angle more than 15 percent to obtain any one of the following gear ratios for 7 seconds: 2.02-2.23 in Reverse, 2.87-3.13 in 1st gear, 1.54-1.71 in 2nd gear, .91-1.07 in 3rd gear and .61-.72 in "D". If DTC P0730 is not present, repair is complete. If DTC P0730 is still present, repeat test.

Check for intermittent input speed sensor or vehicle speed sensor circuit problems, or for possible incorrect calibration.

Torque Converter Clutch (TCC) solenoid is a Pulse Width Modulated (PWM) solenoid. When vehicle operating conditions are appropriate to apply TCC, PCM begins TCC PWM duty cycle at about 42 percent. PCM then increases duty cycle up to 90 percent to achieve full TCC apply pressure.

When TCC PWM is de-energized, solenoid blocks filtered 2-3 drive fluid and allows TCC signal fluid to exhaust. When energized, solenoid modulates fluid into TCC signal fluid circuit. When fully energized, modulation stops and solenoid blocks both 2-3 drive fluid and TCC signal fluid from being exhausted. DTC P0741 will set when PCM detects a high TCC slip speed when TCC is commanded on.

Conditions For Running DTC P0741

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0502, P0503 (vehicle speed sensor), P0742, P1810 (pressure switch assembly) or P1887 are not present.
2. 6 seconds has passed since last manual shift change.
3. Throttle position angle is 8-75 percent.
4. Transaxle fluid temperature is 70-266°F (21-130°C).
5. Transaxle Fluid Pressure (TFP) manual valve position switch indicates "2", "3" or "D" position.
6. PCM commands TCC on for more than 3 seconds.

Conditions For Setting DTC P0741

TCC slip speed is 250 RPM or more for 8 seconds 2 consecutive times.

PCM performs the following if DTC is set

1. Will light MIL after 2 consecutive trips with first failure reported.
2. Inhibits TCC engagement.
3. Freezes shift adapts from being updated.
4. DTC P0741 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Check transaxle fluid. Fill if necessary. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
3. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Drive vehicle at 45 MPH. Using scan tool, command TCC solenoid on. Observe TCC slip speed. If TCC slip speed is less than 50 RPM, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . If TCC slip speed is 50 RPM or more, go to next step.
4. Check TCC PWM shift valve circuit. Inspect for the following: Leak at TCC PWM solenoid, TCC regulator apply valve or control valve stuck in release position, or plugged TCC PWM solenoid filter. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. Repair as necessary. After repairs, go to next step.
5. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0741". Drive vehicle in "D" position with throttle position more than 8 percent to obtain 45 MPH. With TCC commanded on and engaged, slip speed must be less than 50 RPM for 4 seconds. If DTC P0741 is not present, repair is complete. If DTC P0741 is still present, repeat test.

Inspect transaxle fluid level. Transaxle may be in hot mode. Inspect transaxle cooler lines to radiator. Lines may be pinched, plugged or twisted.

Torque Converter Clutch (TCC) solenoid valve is a Pulse Width Modulation (PWM) solenoid. When vehicle operating conditions are appropriate for TCC application, PCM begins TCC duty cycle at about 42 percent. PCM then increases duty cycle up to 90 percent, in order to achieve full TCC-apply pressure. When TCC PWM solenoid valve is de-energized, solenoid blocks filtered 2-3 drive fluid, and allows TCC signal fluid to exhaust. When energized, solenoid modulates fluid into TCC signal fluid circuit. When fully energized, modulation stops, and solenoid blocks both 2-3 drive fluid and TCC signal fluid exhaust. TCC release switch is part of Transmission Fluid Pressure (TFP) manual valve position switch. TFP manual valve position switch is mounted to transaxle valve body. TCC release switch is a normally-closed switch. Switch signals PCM that TCC is released. Torque converter release fluid pressure acts on switch contact, opening signal circuit. When circuit voltage is high, PCM recognizes TCC is no longer engaged. DTC P0742 sets when PCM detects TCC release switch is closed when TCC is commanded off.

Conditions For Running DTC P0742

1. DTCs P0121, P0122, P0123 (throttle position sensor) or P1887 are not present.
2. Engine is running.
3. Throttle position angle is 12-75 percent.
4. TCC is commanded off.
5. Since last manual shift change, 6 seconds has passed .

Conditions For Setting DTC P0742

TCC release switch is closed (release fluid not present) for 6 seconds, 4 times during same trip.

PCM performs the following if DTC is set

1. Will light MIL at first failure signal.
2. Freezes shift adapts from being updated.
3. TCC will be commanded on.
4. DTC P0742 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Using scan tool, observe TCC release pressure. If TCC release pressure is indicated on scan tool, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . If TCC release pressure is not indicated on scan tool, go to next step.
3. Start engine. If scan tool indicates TCC release pressure is indicated, go to step 8 . If TCC release pressure is not indicated, go to next step.
4. Turn ignition off. Disconnect transaxle 20-pin connector. Turn ignition switch to ON position. Using scan tool, observe TCC release pressure. If TCC release pressure is indicated on scan tool, go to step 6 . If TCC release pressure is not indicated on scan tool, go to next step.
5. Check for short to ground in TCC release switch signal circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 12 . If TCC release switch signal circuit is okay, go to step 11 .
6. Check for short to ground in TCC release switch signal circuit between transaxle 20-pin connector and TFP manual valve position switch. If short to ground is found in TCC release switch signal circuit, go to step 10 . If TCC release switch signal circuit is okay, go to next step.
7. Remove TFP manual valve position switch. Inspect TCC release switch for damaged or leaking seal, sediment or debris in switch, damaged and stuck switch contacts. If fault is found with TFP manual valve position switch, go to step 9 . If TFP manual valve position switch is okay, go to next step.
8. Inspect TCC PWM hydraulic circuit. Check for plugged TCC PWM solenoid exhaust, TCC regulator apply valve or control valve stuck in apply position, TCC feed limit valve stuck, causing no or low TCC feed limit pressure and release pressure or stuck pressure regulator valve. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. Repair or replace component as necessary. After repairs, go to step 12 .
9. Replace TFP manual valve position switch. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 12 .
10. Replace internal transaxle wire harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 12 .
11. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
12. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0742". Drive vehicle in "D" position with throttle position angle at 12-75 percent. TCC release fluid must be present at TCC release switch (switch open) for 6 seconds. If DTC P0742 is not present, repair is complete. If DTC P0742 is still present, repeat test.

Rapid fluctuation in line pressure could set DTC P0742. Check for pressure regulator malfunction and low or high line pressure. Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. Customer may notice an engine stalling condition. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

DTC P0748: PRESSURE CONTROL SOLENOID ELECTRICAL MALFUNCTION

Note. Transmission Adaptive Pressure (TAP) values may need to be reset if one of the following repairs has been performed: Transaxle overhaul or replacement. Repair or replacement of an apply or release component (band, clutch, piston and/or servo). Repair or replacement of a component or assembly which directly affects line pressure. To reset TAP values, see CLEARING & RESETTING TAP VALUES under DIAGNOSTIC & TESTING.

Pressure Control Solenoid (PCS) is used to regulate line pressure. PCS consists of an electrical connector, coil, armature, regulating spring and a poppet valve. PCS is attached to upper control valve body. PCM compares TP sensor voltage, fluid temperature, gear status and other inputs to determine line pressure appropriate for given load. PCM will regulate pressure by applying varying amperage to PCS. Applied amperage can vary from .1-1.1 amps. PCM then monitors amperage at return line. DTC P0748 will set when PCM detects a continuous open, short to voltage or short to ground in PCS circuit to PCS solenoid.

Conditions For Running DTC P0748

System voltage is 8-18 volts.

Conditions For Setting DTC P0748

PC solenoid duty cycle is zero percent or more than 95 percent.

PCM performs the following if DTC is set

1. Will not light MIL when fault is set.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure (zero amps).
4. DTC P0748 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Start engine. Using scan tool, apply .1-1.0 amp and observe scan tool display. If PCS actual amperage reading is not within .16 amp of desired reference amperage reading, go to next step. If PCS actual amperage reading is within .16 amp of desired reference amperage reading, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
3. Turn ignition off. Disconnect transaxle 20-pin connector. Install Jumper Harness (J-39775) to transaxle side of 20-pin connector. Using DVOM, measure resistance between terminals "C" and "D" at jumper harness. If resistance is 3-7 ohms, go to step 7 . If resistance is not 3-7 ohms, go to next step.
4. If resistance between terminals "C" and "D" is more than 7 ohms, go to next step. If resistance between terminals "C" and "D" is less than 7 ohms, go to step 6 .
5. Check for open in PCS power feed and ground circuits between transaxle 20-pin connector and PCS. If open is found in PCS power or ground circuits, go to step 17 . If PCS power feed and ground circuits are okay, go to step 18 .
6. Check for shorted together PCS power feed and ground circuits between transaxle 20-pin connector and PCS. If short is found in PCS power feed and ground circuits, go to step 17 . If PCS power feed and ground circuits are okay, go to step 18 .
7. Measure resistance between ground and terminal "D" at jumper harness. If resistance is more than 1000 ohms, go to step 9 . If resistance is 1000 ohms or less, go to next step.
8. Check for short to ground in PCS power feed and ground circuits between transaxle 20-pin connector and PCS. If short to ground is found in PCS power or ground circuits, go to step 17 . If PCS power feed and ground circuits are okay, go to step 18 .
9. Disconnect jumper harness from transaxle 20-pin connector and install harness on PCM side of transaxle 20-pin connector. Disconnect PCM 80-pin connector C2. Measure resistance between ground and terminal "D" at jumper harness. If resistance is less than 10 ohms, go to next step. If resistance is 10 ohms or more, go to step 11 .
10. Check for short to ground in PCS ground circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 20 .
11. Measure resistance of PCS ground circuit between appropriate PCM connector and transaxle 20-pin connector. If resistance is less than 10 ohms, go to step 13 . If resistance is 10 ohms or more, go to next step.
12. Check for open in PCS ground circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 20 .
13. Measure resistance of PCS power feed circuit between ground and transaxle 20-pin connector. If resistance is less than 10 ohms, go to next step. If resistance is 10 ohms or more, go to step 15 .
14. Check for short to ground in PCS power feed circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 20 .
15. Measure resistance of PCS power feed circuit between appropriate PCM connector and transaxle 20-pin connector. If resistance is less than 10 ohms, go to step 19 . If resistance is 10 ohms or more, go to next step.
16. Check for open in PCS power feed circuit between appropriate PCM connector and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 20 .
17. Replace internal transaxle wire harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 20 .
18. Replace PCS. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 20 .
19. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
20. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0748". Turn ignition switch to ON position. PCS actual return amperage must be .16 amp of commanded amperage. If DTC P0748 is not present, repair is complete. If DTC P0748 is still present, repeat test.

Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. Extended engine cranking with a weak battery could set DTC P0748. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

The 1-2 shift solenoid is a normally-open exhaust valve that is used in conjunction with 2-3 shift solenoid, to allow 4 different shifting combinations. Solenoid is attached to control valve body. Malfunctions will occur when shift solenoid or shift valve is stuck on or off. DTC P0751 will set when PCM detects that commanded gear does not match actual gear ratio for particular gear.

Conditions For Running DTC P0751

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0502, P0503 (vehicle speed sensor), P0716, P0717 (input speed sensor), P0753, P0758 or P1810 (pressure switch assembly) are not present.
2. Engine is running.
3. Transaxle Fluid Pressure (TFP) manual valve position switch is not in Park, Reverse or Neutral.
4. Transaxle temperature is more than 70°F (21°C).
5. Throttle position angle is more than 8 percent.
6. Vehicle speed is more than 5 MPH.
7. Engine torque is 10 ft. lbs. (14 N.m).

Conditions For Setting DTC P0751

Any one of the following conditions occur 2 consecutive times

1. PCM commands 1st gear and gear ratio is between 1.54-1.71 (2nd gear) for 2 seconds.
2. PCM commands 2nd gear and gear ratio is between 2.87-3.13 (1st gear) for 4 seconds.
3. PCM commands 3rd gear and gear ratio is between .61-.72 (4th gear) for 5 seconds.
4. PCM commands 4th gear and gear ratio is between .91-1.07 (3rd gear) for 5 seconds.

PCM performs the following if DTC is set

1. Will light MIL at first failure signal.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. Inhibits TCC engagement.
5. DTC P0751 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Check transaxle fluid level. Fill if necessary. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
3. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Use scan tool snapshot mode to record current gear and gear ratio. Drive vehicle in "D" position, to obtain 1-2, 2-3 and 3-4 shifts with throttle position angle of more than 8 percent. When current gear is 2nd, if gear ratio is 2.87:1-3.13:1, go to step 5 . If gear ratio is not 2.87:1-3.13:1, go to next step.
4. When current gear is 1st, if gear ratio is 1.54:1-1.71:1, go to step 6 . If gear ratio is not 1.54:1-1.71:1, go to next step.
5. When current gear is 3rd, if gear ratio is 0.61:1-0.72:1, go to step 7 . If gear ratio is not 0.61:1-0.72:1, go to next step.
6. When current gear is 4th, if gear ratio is 0.91:1-1.07:1, go to step 8 .
7. Inspect 1-2 shift circuit for the following conditions: 1-2 shift solenoid valve mechanically stuck on. 1-2 shift valve stuck in applied position. Repair as necessary. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 9 .
8. Inspect 1-2 shift circuit for the following conditions: 1-2 shift solenoid valve mechanically stuck off. Damaged 1-2 shift solenoid valve "O" ring. 1-2 shift valve stuck in released position. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to next step.
9. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0751". Drive vehicle in "D" position. Allow transaxle to shift through all gears. Actual gear ratios must match commanded gears for .75 seconds for all gears. If DTC P0751 is not present, repair is complete. If DTC P0751 is still present, repeat test.

Check for stuck throttle position sensor. If DTC P0751 cannot be reset after clearing DTC, check for possible fluid contamination or plugged or restricted oil circuits.

The 1-2 shift solenoid valve is a normally-open exhaust valve that is used in conjunction with 2-3 shift solenoid valve, allows four different shifting combinations. The 1-2 shift solenoid valve is attached to control valve body, within transaxle. PCM monitors actual gear ratio, and compares actual gear ratio with commanded gear ratio. DTC P0752 sets when PCM detects a 1-1-4-4 shift pattern.

Conditions For Running DTC P0752

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0502, P0503 (vehicle speed sensor), P0716, P0717 (input speed sensor), P0753, P0758 or P1810 (pressure switch assembly) are not present.
2. Engine is running.
3. TFP manual valve position switch is not indicating Park, Reverse or Neutral.
4. Transaxle fluid temperature is more than 70°F (21°C).
5. Throttle position angle is more than 8 percent.
6. Vehicle speed is more than 5 MPH.
7. Engine torque is more than 5 ft. lbs. (7 N.m) when 2nd gear is commanded and more than 20 ft. lbs. (27 N.m) when 3rd gear is commanded.

Conditions For Setting DTC P0752

Any one of the following conditions occur 2 consecutive times

1. PCM commands 2nd gear and gear ratio is 2.87:1-3.13:1 (1st gear) for 4 seconds.
2. PCM commands 3rd gear and gear ratio is 0.61:1-0.72:1 (4th gear) for 4 seconds.

1. Will light MIL after 2 consecutive trips with first failure reported.
2. Commands maximum line pressure.
3. Inhibits TCC engagement.
4. Inhibits 3-2 downshifts above 35 MPH.
5. Freezes shift adapts from being updated.
6. DTC P0752 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Perform OBD system check. See «ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. After performing OBD system check, go to next step.
2. Check transaxle fluid level. Fill if necessary. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
3. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Use scan tool snapshot mode to record current gear and gear ratio. Drive vehicle in "D" position, to obtain 1-2, 2-3 and 3-4 shifts with throttle position angle more than 8 percent. If current gear and gear ratio are 1st/2nd 2.87:1-3.13:1 and 3rd/4th 0:61:1-0.72:1, go to next step. If current gear and gear ratio are not 1st/2nd 2.87:1-3.13:1 and 3rd/4th 0:61:1-0.72:1, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
4. Inspect 1-2 shift circuit for 1-2 shift solenoid valve mechanically stuck on and 1-2 shift valve stuck in applied position. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to next step.
5. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0752". Drive vehicle in "D" position. Allow transaxle to shift through all gears. Actual gear ratios must match commanded gears for .75 seconds for all gears. If DTC P0752 is not present, repair is complete. If DTC P0752 is still present, repeat test.

Check for stuck throttle position sensor. If DTC P0752 cannot be reset after clearing DTC, check for possible fluid contamination or plugged or restricted oil circuits.

The 1-2 shift solenoid is used to control fluid flow acting on 1-2 shift valve. Solenoid is a normally-open valve that is used in conjunction with 2-3 shift solenoid, to allow 4 different shifting combinations. See SHIFT SOLENOID COMBINATIONS table. Solenoid is attached to control valve body. Ignition voltage is supplied directly to solenoid through fused circuit. PCM commands solenoid on or off by providing a ground path. DTC P0753 will set when PCM detects a continuous open, short to ground or short to voltage in 1-2 shift solenoid circuit.

Conditions For Running DTC P0753

1. Ignition is on.
2. System voltage is 8-18 volts.

Conditions For Setting DTC P0753

DTC will set under the following conditions

1. PCM commands solenoid on and voltage remains high (battery voltage) for 4.3 seconds.
2. PCM commands solenoid off and voltage remains low (zero volts) for 4.3 seconds.

PCM performs the following if DTC is set

1. Will light MIL at first failure signal.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. Inhibits TCC engagement.
5. DTC P0753 will be stored in PCM history.

SHIFT SOLENOID COMBINATIONS

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Ensure on-board diagnostic system check has been performed. See «ON-BOARD DIAGNOSTIC SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. Go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Data will be lost when DTCs are cleared later in this test. If DTCs P0753 or P1860 are not present, go to step 8. If DTCs P0758 or P1860 are present, go to next step.
3. Remove ERLS fuse 10-amp ("J" body) from instrument panel fuse block or AUTO TRANS fuse ("N" body) from underhood fuse block and inspect fuse. Replace fuse if necessary. If fuse was open, go to next step. If fuse is okay, go to step 6.
4. Check for short to ground in 1-2 shift solenoid valve power feed circuit between transaxle 20-pin connector and applicable fuse block. Repair circuit as necessary. After repairs, go to step 24. If circuit is okay, go to next step.
5. Check 1-2 shift solenoid valve power feed circuit for short to ground between transaxle 20-pin connector and 1-2 shift solenoid (internal harness). Go to step 21.
6. Check for open in 1-2 shift solenoid valve power feed circuit between transaxle 20-pin connector and applicable fuse block. Repair as necessary. After repairs, go to step 24. If circuit is okay, go to next step.
7. Check for open in 1-2 shift solenoid valve power feed circuit between transaxle 20-pin connector and 1-2 shift solenoid (internal harness). Go to step 21.
8. Using scan tool, command 1-2 shift solenoid on and off 3 times. Listen at transaxle side cover. If solenoid does not click when commanded on and off, go to next step. If solenoid clicks when commanded on and off, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e).
9. Turn ignition off. Disconnect transaxle 20-pin connector. Install Jumper Harness (J-44152) to PCM side of transaxle 20-pin connector. Connect test light between terminals "A" and "E" of transaxle 20-pin connector. (Scheme 109) Turn ignition switch to ON position. Using scan tool, command 1-2 shift solenoid on and off 3 times. If test light cycles on and off 3 times, go to step 16. If test light does not cycle on and off 3 times, go to next step.
10. If test light is always illuminated, go to next step. If test light is always off, go to step 13.
11. Turn ignition off. Disconnect PCM 80-pin connector C2 on 2.2L and 2.4L models or PCM 80-pin connector C1 on 3.1L and 3.4L models. On all models, turn ignition on. Ensure test light is still connected between terminals "A" and "E" of transaxle 20-pin connector. If test light is off, go to step 23. If test light is on, go to next step.
12. Check for short to ground in 1-2 shift solenoid valve control circuit between transaxle 20-pin connector and PCM. Repair as necessary. After repairs, go to step 24. If circuit is okay, go to next step.
13. Check for open in 1-2 shift solenoid valve control circuit between transaxle 20-pin connector and PCM. Repair circuit as necessary. After repairs, go to step 24. If circuit is okay, go to next step.
14. Connect test light between ground and terminal "A" on transaxle 20-pin connector. If test light is on, go to next step. If test light is off, go to step 23.
15. Check for short to voltage in 1-2 shift solenoid valve control circuit between transaxle 20-pin connector and PCM. Repair as necessary. After repairs, go to step 24.
16. Turn ignition off. Disconnect jumper harness from PCM side of transaxle 20-pin connector and install harness to transaxle side of 20-pin connector. Measure resistance between terminals "A" and "E" of transaxle 20-pin connector. If resistance is 19-31 ohms, go to step 19. If resistance is not 19-31 ohms, go to next step.
17. If resistance is more than 250 ohms, go to next step. If resistance is 250 ohms or less, go to step 19.
18. Check for open in 1-2 shift solenoid valve power feed and control circuit between transaxle 20-pin connector and 1-2 shift solenoid (internal harness). If either circuit is open, go to step 21. If both circuits are okay, go to step 22.
19. Measure resistance between ground and terminal "A" of transaxle 20-pin connector. If resistance is more than 1000 ohms, go to step 22. If resistance is 1000 ohms or less, go to next step.
20. Check for short to ground in 1-2 shift solenoid control circuit between transaxle 20-pin connector and 1-2 shift solenoid. Go to next step.
21. Replace transaxle internal wiring harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. Go to step 24.
22. Replace 1-2 shift solenoid valve. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. Go to step 24.
23. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
24. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC P0753. Place transaxle in Park and start engine. Allow engine to idle for 5 seconds. If DTC P0753 is not present, repair is complete. If DTC P0753 is still present, repeat test.

An open in circuit wire between transaxle 20-pin connector and fuse can cause multiple DTCs to set. Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

The 2-3 shift solenoid is a normally-open exhaust valve that is used in conjunction with 1-2 shift solenoid, to allow 4 different shifting combinations. Solenoid is attached to control valve body. Malfunctions will occur when shift solenoid or shift valve is stuck on or off.

DTC P0756 will set when PCM detects a 4-3, 3-4 shift pattern caused by a stuck on 2-3 shift solenoid valve or stuck on 2-3 shift valve.

Conditions For Running DTC P0756

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0502, P0503 (vehicle speed sensor), P0716, P0717 (input speed sensor), P0753, P0758, P1644 or P1810 (pressure switch assembly) are not present.
2. Engine is running.
3. Transaxle Fluid Pressure (TFP) manual valve position switch indicates "D4", "D3", "D2" or "D1".
4. Transaxle fluid temperature is more than 70°F (21°C).
5. Vehicle speed is more than 5 MPH.
6. Throttle position angle is more than 8 percent.

Conditions For Setting DTC P0756

All conditions exist when any one of the following conditions occur

1. PCM commands 1st gear and gear ratio is between .61-.72 (4th gear) for 2 seconds. This must occur 2 consecutive times.
2. PCM commands 2nd gear and gear ratio is between .91-1.07 (3rd gear) for 5 seconds. This must occur 2 consecutive times.
3. PCM commands 3rd gear and gear ratio is between 1.54-1.71 (2nd gear) for 5 seconds. This must occur 2 consecutive times.
4. PCM commands 4th gear and gear ratio is between 2.87-3.13 (1st gear) for 5 seconds. This must occur 2 consecutive times.

PCM performs the following if DTC is set

1. Will light MIL at first failure signal.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. Commands immediate shift to 2nd gear.
5. Inhibits TCC engagement.
6. DTC P0756 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Ensure on-board diagnostic system check has been performed. See «ON-BOARD DIAGNOSTIC SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. Go to next step.
2. Check transaxle fluid level. Fill if necessary. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
3. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Select snapshot mode on scan tool. Record current gear and gear ratio. Drive vehicle in "D" position to obtain 1-2, 2-3 and 3-4 shifts with throttle position angle more than 8 percent and vehicle speed more than 5 MPH for 5 seconds. If 1st/4th gear ratio is .61:1-.72:1 and 2nd/3rd gear ratio is .91:1-1.07:1, go to next step. If 1st/4th gear ratio is not .61:1-.72:1 and 2nd/3rd gear ratio is not .91:1-1.07:1, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
4. Determine if engine labors during start off and 3rd gear is indicated when 1st gear is commanded. If engine does not labor during start off and 3rd is not indicated when 1st gear is commanded, go to next step. If engine labors during start off and 3rd gear is indicated when 1st gear is commanded, go to step 6 .
5. Repair 2-3 shift circuit. Check 2-3 shift circuit for 2-3 shift solenoid mechanically stuck off, 2-3 shift solenoid "O" ring damage or 2-3 shift valve stuck in released (downshift) position. Repair as necessary, then go to step 7 .
6. Repair 2-3 shift circuit. Check 2-3 shift circuit for 2-3 shift solenoid mechanically stuck on, or 2-3 shift valve stuck in applied (upshift) position. Repair as necessary, then go to next step.
7. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0756". Drive vehicle in "D" position. Allow transaxle to shift through all gears. Actual gear ratios must match commanded gears for .75 seconds for all gears. If DTC P0756 is not present, repair is complete. If DTC P0756 is still present, repeat test.

If DTC P0756 cannot be reset after clearing DTC, check for possible fluid contamination or plugged or restricted oil circuit.

The 2-3 shift solenoid is a normally-open exhaust valve that is used in conjunction with 1-2 shift solenoid, to allow 4 different shifting combinations. Solenoid is attached to control valve body. Malfunctions will occur when shift solenoid or shift valve is stuck on or off.

DTC P0757 will set when PCM detects a 1-2, 2-1 shift pattern caused by a stuck off 2-3 shift solenoid valve or stuck off 2-3 shift valve.

Conditions For Running DTC P0757

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0502, P0503 (vehicle speed sensor), P0716, P0717 (input speed sensor), P0753, P0758, DTC P1644 or P1810 (pressure switch assembly) are not present.
2. Engine is running.
3. Transaxle Fluid Pressure (TFP) manual valve position switch indicates "D4", "D3", "D2" or "D1".
4. Transaxle fluid temperature is more than 70°F (21°C).
5. Vehicle speed is more than 5 MPH.
6. Throttle position angle is more than 8 percent.

Conditions For Setting DTC P0757

All conditions exist when any one of the following conditions occur

1. PCM commands 3rd gear and gear ratio is between 1.54-1.71 (2nd gear) for 5 seconds. This must occur 2 consecutive times.
2. PCM commands 4th gear and gear ratio is between 2.87-3.13 (1st gear) for 5 seconds. This must occur 2 consecutive times.

PCM performs the following if DTC is set

1. Will light MIL at first failure signal.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. Commands immediate shift to 2nd gear.
5. Inhibits TCC engagement.
6. DTC P0757 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Ensure on-board diagnostic system check has been performed. See «ON-BOARD DIAGNOSTIC SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. Go to next step.
2. Check transaxle fluid level. Fill if necessary. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
3. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Select snapshot mode on scan tool. Record current gear and gear ratio. Drive vehicle in "D" position to obtain 2-3 shift with throttle position angle more than 8 percent and vehicle speed more than 5 MPH for 5 seconds. If 1st/4th gear ratio is not 2.87:1-3.13:1, and 2nd/3rd gear ratio is not 1.54:1-1.71:1, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) . If 1st/4th gear ratio is 2.87:1-3.13:1, and 2nd/3rd gear ratio is 1.54:1-1.71:1, go to next step.
4. Repair 2-3 shift circuit. Check 2-3 shift circuit for 2-3 shift solenoid mechanically stuck off, 2-3 shift solenoid "O" ring damage or 2-3 shift valve stuck in released (downshift) position. Repair as necessary, then go to next step.
5. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0757". Drive vehicle in "D" position. Allow transaxle to shift through all gears. Actual gear ratios must match commanded gears for .75 seconds for all gears. If DTC P0757 is not present, repair is complete. If DTC P0757 is still present, repeat test.

If DTC P0757 cannot be reset after clearing DTC, check for possible fluid contamination or plugged or restricted oil circuit.

The 2-3 shift solenoid is used to control fluid flow acting on 2-3 shift valve. Solenoid is a normally-open valve that is used in conjunction with 1-2 shift solenoid, to allow 4 different shifting combinations. See SHIFT SOLENOID COMBINATIONS table. Solenoid is attached to control valve body. Ignition voltage is supplied directly to solenoid through fused circuit. PCM commands solenoid on or off by providing a ground path. DTC P0758 will set when PCM detects a continuous open, short to ground or short to voltage in 2-3 shift solenoid circuit.

Conditions For Running DTC P0758

1. Ignition is on.
2. System voltage is 8-18 volts.

Conditions For Setting DTC P0758

DTC will set under the following conditions

1. PCM commands solenoid on and voltage remains high for 4.3 seconds.
2. PCM commands solenoid off and voltage remains low for 4.3 seconds.

PCM performs the following if DTC is set

1. Will light MIL at first failure signal.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. Commands immediate shift to 2nd gear.
5. Inhibits TCC engagement.
6. DTC P0758 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Ensure on-board diagnostic system check has been performed. See «ON-BOARD DIAGNOSTIC SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. Go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. If DTCs P0753 or P1860 are not present, go to step 8. If DTCs P0753 or P1860 are present, go to next step.
3. Remove ERLS fuse (10-amp) ("J" body) from instrument panel fuse block or AUTO TRANS fuse ("N" body) from underhood fuse block and inspect fuse. Replace fuse if necessary. If fuse was open, go to next step. If fuse is okay, go to step 6.
4. Check for short to ground in 2-3 shift solenoid valve power feed circuit between transaxle 20-pin connector and applicable fuse block. Repair as necessary. After repairs, go to step 24. If circuit is okay, go to next step.
5. Check 2-3 shift solenoid valve power feed circuit for short to ground between transaxle 20-pin connector and 2-3 shift solenoid (internal harness). Go to step 21.
6. Check for open in 2-3 shift solenoid valve power feed circuit between transaxle 20-pin connector and applicable fuse block. Repair as necessary. After repairs, go to step 24. If circuit is okay, go to next step.
7. Check for open in 2-3 shift solenoid valve power feed circuit between transaxle 20-pin connector and 2-3 shift solenoid (internal harness). Go to step 21.
8. Using scan tool, command 2-3 shift solenoid on and off 3 times. Listen at transaxle side cover. If solenoid does not click when commanded on and off, go to next step. If solenoid clicks when commanded on and off, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e).
9. Turn ignition off. Disconnect transaxle 20-pin connector. Install Jumper Harness (J-44152) to PCM side of transaxle 20-pin connector. Connect test light between terminals "B" and "E" of transaxle 20-pin connector. (Scheme 109) Turn ignition switch to ON position. Using scan tool, command 2-3 shift solenoid on and off 3 times. If test light cycles on and off 3 times, go to step 16. If test light does not cycle on and off 3 times, go to next step.
10. If test light is always illuminated, go to next step. If test light is always off, go to step 13.
11. Turn ignition off. Disconnect PCM 80-pin connector C2 on 2.2L and 2.4L models or connector C1 on 3.1L and 3.4L models. On all models, turn ignition on. Ensure test light is still connected between terminals "B" and "E" of transaxle 20-pin connector. If test light is off, go to step 23. If test light is on, go to next step.
12. Check 2-3 shift solenoid valve control circuit for short to ground between transaxle 20-pin connector and PCM. Repair as necessary. After repairs, go to step 24. If circuit is okay, go to next step.
13. Check for open in 2-3 shift solenoid valve control circuit between transaxle 20-pin connector and PCM. Repair circuit as necessary, then go to step 24. If circuit is okay, go to next step.
14. Connect test light between ground and terminal "B" on transaxle 20-pin connector. If test light is on, go to next step. If test light is off, go to step 23.
15. Check for short to voltage in 2-3 shift solenoid valve control circuit between transaxle 20-pin connector and PCM. Repair as necessary. After repairs, go to step 24.
16. Turn ignition off. Disconnect jumper harness from PCM side of transaxle 20-pin connector and install harness to transaxle side of 20-pin connector. (Scheme 109) Measure resistance between terminals "B" and "E" of transaxle 20-pin connector. If resistance is 19-31 ohms, go to step 19. If resistance is not 19-31 ohms, go to next step.
17. If resistance is more than 250 ohms, go to next step. If resistance is 250 ohms or less, go to step 19.
18. Check for open in 2-3 shift solenoid valve power feed and control circuits between transaxle 20-pin connector and 2-3 shift solenoid (internal harness). If either circuit is open, go to step 21. If both circuits are okay, go to step 22.
19. Measure resistance between ground and terminal "B" of transaxle 20-pin connector. If resistance is more than 1000 ohms, go to 22. If resistance is 1000 ohms or less, go to next step.
20. Check for short to ground in 2-3 shift solenoid valve control circuit between transaxle 20-pin connector and 2-3 shift solenoid. Go to next step.
21. Replace transaxle internal wiring harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 24.
22. Replace 2-3 shift solenoid valve. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 24.
23. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
24. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P0758". Place transaxle in Park and start engine. Allow engine to idle for 5 seconds. If DTC P0758 is not present, repair is complete. If DTC P0758 is still present, repeat test.

An open in circuit wire between shift solenoid and fuse can cause multiple DTCs to set. Check for stuck throttle position sensor. Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

DTC P1810: PRESSURE SWITCH ASSEMBLY MALFUNCTION

Note. Pressure Switch Assembly (PSA) is also referred to as Transmission Fluid Pressure (TFP) manual valve position switch.

Transmission Pressure Switch Assembly (pressure switch assembly) consists of 6 pressure switches. One switch is normally-closed and is used to detect TCC release fluid pressure. Other switches are normally-open and are used for determining gear range selection. PSA contains Transmission Fluid Temperature (TFT) sensor. These components are combined into one unit and mounted on control valve body.

PCM provides battery voltage on each range signal. By grounding one or more switches with fluid pressure from manual shift valve, PCM detects selected gear range. When transaxle electrical connector is disconnected and ignition is on, ground potential for 3 range signals from PCM will be removed, and an illegal gear will be indicated. See PSA LOGIC table. DTC P1810 will set when PCM detects an invalid gear status, a drive range after start-up or an incorrect gear ratio.

PSA LOGIC

Conditions For Running DTC P1810

1. An invalid gear state.
2. Any drive range after start-up.
3. An incorrect gear ratio.
4. Engine is running.
5. System voltage is 8-18 volts.

Conditions For Setting DTC P1810

DTC will set under any one of the following 3 conditions occur

Condition No. 1

1. Gear range is illegal for 60 seconds. See «PSA LOGIC»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) table.

Condition No. 2

1. D2, D4 or Reverse gear is indicated after start-up for 3 seconds.
2. DTCs P0502 or P0503 (vehicle speed sensor) are not present.
3. Vehicle speed is less than 2 MPH.

Condition No. 3

1. DTCs P0121, P0122, P0123 (throttle position sensor), P0502 or P0503 (vehicle speed sensor), P0716, P0717 (input speed sensor) are not present.
2. DTCs P0751, P0752, P0753, P0756, P0757 or P0758 are not present.
3. Engine torque is more than 10 ft. lbs. ( 14 N.m).
4. Throttle position angle is equal to or more than 10 percent.
5. Vehicle speed is 5 MPH or more.

One of the following 3 conditions must also occur

1. PSA indicates Park/Neutral when gear ratio is less than .72 (4th gear) for 5 seconds.
2. PSA indicates Reverse when gear ratio is more than 2.23 or less than 2.02 for 5 seconds.
3. PSA indicates gear position other than Park or Neutral when gear ratio indicates Reverse for 5 seconds.

PCM performs the following if DTC is set

1. Will light MIL after 2 consecutive trips with a failure signal.
2. Freezes shift adapts from being updated.
3. Increases line pressure.
4. Assumes "D" shift pattern.
5. Inhibits TCC engagement.
6. DTC P1810 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Ensure on-board diagnostic system check has been performed. See «ON-BOARD DIAGNOSTIC SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. Go to next step.
2. Check transaxle fluid. Fill as needed. Ensure transaxle shift linkage is adjusted correctly. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
3. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Apply parking brake. Start engine and apply brake. Shift transaxle into each selector lever position while monitoring scan tool Transaxle Range (TR) switch display. See «PSA LOGIC»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) table. If each selected lever position does not match scan tool display, go to next step. If each selected lever position matches scan tool display, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
4. Turn ignition off. Disconnect transaxle 20-pin connector. Turn ignition switch to ON position. Using scan tool, monitor TFP switch A/B/C parameter. If HI indicated for all ranges, go to next step. If HI is not indicated for all ranges, go to step 9 .
5. Turn ignition off. Install Jumper Harness (J-44152) to PCM side of transaxle 20-pin connector. Turn ignition switch to ON position. Measure voltage between ground and terminals "N", "R" and "P" (range signal circuits) on PCM side of transaxle 20-pin connector. If battery voltage is present at all 3 circuits, go to next step. If battery voltage is not present at all 3 circuits, go to step 10 .
6. Connect fused jumper wire between ground and PCM side of transaxle 20-pin connector terminal "N". Using scan tool, verify that only TFP switch signal "A" is grounded. If signal "A" is grounded. Go to next step. If other TFP switch signal circuits indicate grounded condition, go to step 11 .
7. Connect fused jumper wire between ground and PCM side of transaxle 20-pin connector terminal "R". Using scan tool, verify that only TFP switch signal "B" is grounded. If signal "B" is grounded. Go to next step. If other TFP switch signal circuits indicate grounded condition, go to step 11 .
8. Connect fused jumper wire between ground and PCM side of transaxle 20-pin connector terminal "P". Using scan tool, verify that only TFP switch signal "C" is grounded. If signal "C" is grounded. If other TFP switch signal circuits indicate grounded condition, go to step 11 . If no TFP switch signal circuits indicate grounded condition, go to step 12 .
9. Check all TFP switch signal circuits for short to ground between PCM and transaxle 20-pin connector. Repair suspect circuit(s) as necessary. After repairs, go to step 16 . If all circuits are okay, go to step 15 .
10. Check for open in all TFP switch signal circuits between PCM and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 16 . If all circuits are okay, go to step 15 .
11. Check all TFP switch signal circuits between PCM and transaxle 20-pin connector for short to each other. Repair as necessary. After repairs, go to step 16 . If all circuits are okay, go to step 15 .
12. Check all TFP switch signal circuits between transaxle 20-pin connector and TFP manual valve position switch (internal harness) for open or shorted condition. If open or shorted condition exists, go to next step. If all circuits are okay, go to step 14 .
13. Replace transaxle internal wiring harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 16 .
14. Replace TFP manual valve position switch. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 16
15. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
16. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC P1810. Drive vehicle in "D" position with throttle position angle more than 10 percent. Allow transaxle to shift through all gears. If DTC P1810 is not present, repair is complete. If DTC P1810 is still present, repeat test.

A pressure regulator malfunction could set DTC P1810. Inspect wiring for poor connections at PCM and at transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

Line pressure is modified by PCM through Pressure Control Solenoid (PCS) to control gear shift execution time and shift consistency. PCM monitors various inputs and modifies shift execution and timing by applying a calculated duty cycle to PCS. PCM alters shifting based on driving habits, transaxle load and internal transaxle condition. DTC P1811 will set when PCM detects long shifts that cannot be shortened by shift adapts during same ignition cycle.

Conditions For Running DTC P1811

1. Shift is adaptable.
2. Shift adapt is at limit.

Conditions For Setting DTC P1811

Shift time is more than .65 seconds twice during ignition cycle.

PCM performs the following if DTC is set

1. Will not light MIL when fault is set.
2. Freezes shift adapts from being updated.
3. Commands maximum line pressure.
4. DTC P1811 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Ensure on-board diagnostic system check has been performed. See «ON-BOARD DIAGNOSTIC SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. Go to next step.
2. Check transaxle fluid. Fill as needed. See appropriate AUTOMATIC TRANSMISSION SERVICING article in TRANSMISSION SERVICING. Go to next step.
3. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record failure records for reference. Clear DTC. Select snapshot on scan tool to record shift times. Drive vehicle in D4 to obtain 1-2, 2-3 and 3-4 upshifts. If all shifts exceeded .65 seconds, go to next step. If all shifts did not exceed .65 seconds, go to step 6 .
4. Perform line pressure test. See HYDRAULIC PRESSURE TEST under PERFORMANCE TESTS in HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. If line pressure is not within specification, go to next step. If line pressure is within specification, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
5. Inspect transaxle for low fluid level caused by external leaks, fluid filter clogged or out of position, internal fluid passage leaks, casting porosity or damage, damaged or out of position gaskets or spacer plate. Check for contaminated, stuck or damaged PCS or pressure regulator valve stuck or leaking. Check for stuck or leaking torque signal valve, leaking or damaged oil pump, or inadequate suction or pump cavitation. Repair component(s) as necessary, then go to step 12 .
6. If 1-2 shift exceeded .65 seconds, go to step 9 . If 1-2 shift did not exceed .65 seconds, go to next step.
7. If 2-3 shift exceeded .65 seconds, go to step 10 . If 2-3 shift did not exceed .65 seconds, go to next step.
8. If 3-4 shift exceeded .65 seconds, go to step 11 .
9. Repair 1-2 shift circuit. Inspect for leaking, rolled or cut 1-2 accumulator piston or 2nd clutch piston seals. Inspect for burned or damaged 2nd clutch plates, broken or out of position 2nd clutch springs, cracked or damaged 2nd clutch piston, leaking or damaged driven sprocket support seals, internal fluid passage leaks, casting porosity or damage, or damaged or out of position gaskets or spacer plate. Inspect for slipping forward clutch, cracked or damaged driven sprocket support, damaged 2nd roller clutch or sprag clutch or 2nd roller clutch or sprag clutch not holding. Repair or replace components as necessary, then go to step 12 .
10. Repair 2-3 shift circuit. Inspect for leaking, rolled or cut 2-3 accumulator or direct clutch piston seals, burned or damaged direct clutch plates, broken or out of position direct clutch springs, cracked or damaged direct clutch piston, leaking or damaged driven sprocket support seals, cracked or damaged driven sprocket support, damaged sprag clutch or sprag clutch not holding. Check for internal fluid passage leaks, casting porosity or damage, or damaged or out of position gaskets or spacer plate. Repair or replace components as necessary, then go to step 12 .
11. Repair 3-4 shift circuit. Inspect for leaking, rolled or cut 3-4 accumulator piston or intermediate/4th servo piston seals and burned, damaged, slipping or out of position intermediate/4th band. Check for internal fluid passage leaks, casting porosity or damage, or damaged or out of position gaskets or spacer plate. Inspect direct clutch for slipping, damaged or seized intermediate/4th servo pin, damaged intermediate/4th servo piston or cracked or leaking intermediate/4th servo cover. Repair or replace components as necessary, then go to next step.
12. Change transaxle fluid and filter. Ensure fluid is at correct level. Using scan tool, clear TAPS function. Go to next step.
13. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P1811". Drive vehicle in D4 to obtain 1-2, 2-3 and 3-4 upshift. Shift times must be less than .65 seconds. If DTC P1811 is not present, repair is complete. If DTC P1811 is still present, repeat test.

Question owner about vehicle overloading, exceeding trailer towing limit or towing in overdrive. If after several unsuccessful attempts to gain accurate shift times and an adapt can be made, reset adapts and operate vehicle to assure proper shifting.

Torque Converter Clutch (TCC) Pulse Width Modulated (PWM) solenoid is a normally closed solenoid used to control apply and release of converter clutch. PCM operates TCC PWM solenoid with a negative duty cycle. When vehicle operating conditions are appropriate to apply TCC, PCM immediately increases duty cycle to about 42 percent. PCM then increases duty cycle to about 90 percent to achieve full TCC apply pressure. When solenoid is commanded on, PCM will detect high voltage. When solenoid is commanded off, PCM will detect low voltage. DTC P1860 will set when PCM detects a continuous open, short to ground or short to voltage in TCC PWM solenoid circuit.

Conditions For Running DTC P1860

1. System voltage is 8-18 volts.
2. Engine has been running for more than 5 seconds, and is not in fuel shut off mode.
3. TCC duty cycle is less than 10 percent or more than 90 percent.

Conditions For Setting DTC P1860

PCM detects an open, short to ground or short to voltage in TCC PWM solenoid circuit within 5 seconds.

PCM performs the following if DTC is set

1. Will light MIL at first failure signal.
2. Inhibits TCC engagement.
3. Freezes shift adapts from being updated.
4. DTC P1860 will be stored in PCM history.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

1. Ensure on-board diagnostic system check has been performed. See «ON-BOARD DIAGNOSTIC SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. Go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. If DTCs P0753 and P0758 are present, go to next step. If DTCs P0753 and P0758 are not present, go to step 8 .
3. Remove ERLS fuse (10-amp) ("J" body) from instrument panel fuse block or AUTO TRANS fuse ("N" body) from underhood fuse block. Inspect fuse. Replace fuse if necessary. If fuse was open, go to next step. If fuse is okay, go to step 24 .
4. Check for short to ground in TCC PWM solenoid valve power feed circuit between transaxle 20-pin connector and fuse block. Repair as necessary. After repairs, go to step 24 . If circuit is okay, go to next step.
5. Check for short to ground in TCC PWM solenoid valve power feed circuit between transaxle 20-pin connector and 2-3 shift solenoid (internal harness). If short is found, go to step 21 .
6. Turn ignition off. Check for open in TCC PWM solenoid valve power feed circuit between transaxle 20-pin connector and fuse block. Repair circuit as needed and go to step 24 . If circuit is okay, go to next step.
7. Check for open in TCC PWM solenoid valve power feed circuit between transaxle 20-pin connector and 2-3 shift solenoid (internal harness). Go to step 21 .
8. Turn ignition off. Disconnect transaxle 20-pin connector. Install Jumper Harness (J-44152) to PCM side of transaxle 20-pin connector. Connect a test light between terminals "E" and "T" on transaxle 20-pin harness connector. Turn ignition switch to ON position. If test light is illuminated, go to next step. If test light is not illuminated, go to step 11 .
9. Turn ignition off. Disconnect PCM connector C2. Turn ignition switch to ON position. Ensure test light is still connected between terminals "E" and "T" on transaxle 20-pin harness connector. If test light is not illuminated, go to step 23 . If test light is illuminated, go to next step.
10. Check for short to ground in TCC PWM solenoid valve control circuit between PCM and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 24 .
11. Using scan tool, command TCC PWM solenoid valve on and off 3 times. If test light cycles on and off 3 times, go to step 16 . If test light does not cycle on and off 3 times, go to next step.
12. Test light should be off at all times. Go to next step.
13. Check for open in TCC PWM solenoid valve control circuit between PCM and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 24 . If circuit is okay, go to next step.
14. Connect test light between ground and terminal "T" at transaxle 20-pin harness connector. If test light is not illuminated, go to step 11 . If test light is illuminated, go to next step.
15. Check for short to voltage in TCC PWM solenoid valve control circuit between PCM and transaxle 20-pin connector. Repair as necessary. After repairs, go to step 24 .
16. Turn ignition off. Disconnect jumper harness from PCM side of transaxle 20-pin connector and install harness to transaxle side of 20-pin connector. Measure resistance between terminals "E" and "T" at transaxle 20-pin connector. If resistance is 10-15 ohms, go to step 19 . If resistance is not 10-15 ohms, go to next step.
17. If resistance is more than 250 ohms, go to next step. If resistance is 250 ohms or less, go to step 19 .
18. Check for open in TCC PWM solenoid valve power feed and control circuit between transaxle 20-pin connector and TCC PWM solenoid valve (internal harness). If either circuit is open, go to step 21 . If both circuits are okay, go to step 22 .
19. Measure resistance between ground and terminal "T" on transaxle 20-pin connector. If resistance is more than 1000 ohms, go to step 22 . If resistance is 1000 ohms or less, go to next step.
20. Check for short to ground in TCC PWM solenoid valve control circuit between transaxle 20-pin connector and TCC PWM solenoid valve (internal harness). Go to next step.
21. Replace transaxle internal wiring harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 24 .
22. Replace TCC PWM solenoid valve. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 24 .
23. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
24. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P1860". Road test vehicle in D4 and increase vehicle speed until TCC applies. Ensure TCC duty cycle is 10-90 percent for more than 5 seconds. If DTC P1860 is not present, repair is complete. If DTC P1860 is still present, repeat test.

Ensure transaxle fluid level is correct. Inspect PCM, transaxle and TCC PWM solenoid connectors for bent, broken or backed out terminals. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. Check for moisture or corrosion. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

Torque Converter Clutch (TCC) release switch is part of Pressure Switch Assembly (pressure switch assembly) which is mounted to control valve assembly. Normally-closed switch provides a signal to PCM to indicate when TCC is released. This is accomplished by torque converter release fluid pressure acting on switch contact and opening circuit. When voltage is high on circuit, PCM recognizes TCC is no longer engaged. DTC P1887 will set when PCM detects TCC release switch is open, indicating TCC is not applied, and TCC slip speed indicates TCC is engaged.

Conditions For Running DTC P1887

1. DTCs P0716, P0717 (input speed sensor), P0741 or P0742, are not present.
2. Engine is running.
3. Transaxle Fluid Pressure (TFP) manual valve position switch is in D4.
4. Engine torque is more than 33 ft. lbs. (45 N.m).
5. TCC is commanded on.
6. TCC slip speed is between -20 RPM and 40 RPM.

Conditions For Setting DTC P1887

TCC release pressure is present for 6 seconds twice during same trip.

PCM performs the following if DTC is set

1. Will light MIL after 2 consecutive trips with a failure signal.
2. Freezes shift adapts from being updated.
3. Inhibits TCC engagement.
4. DTC P1887 will be stored in PCM history after conditions are met during 2 consecutive trips.

Note. For connector end views and component locations (Scheme 109)- (Scheme 113). For circuit locations, see WIRING DIAGRAMS.

Note. Pressure Switch Assembly (pressure switch assembly) may also be known as Transmission Fluid Pressure (TFP) manual valve position switch.

1. Ensure on-board diagnostic system check has been performed. See «ON-BOARD DIAGNOSTIC SYSTEM CHECK»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e__on-board-diagnostic-obd-system-check) under DIAGNOSIS & TESTING. Go to next step.
2. Connect scan tool to DLC. Turn ignition switch to ON position. Using scan tool, record freeze frame and failure records for reference. Clear DTC. Using scan tool, monitor TCC release pressure. If TCC release pressure is present, go to next step. If TCC release pressure is not present, go to step 6 .
3. Turn ignition off. Install Jumper Harness (J-44152) to PCM side of transaxle 20-pin connector. Connect fused jumper between ground and terminal "U" on transaxle 20-pin harness connector. Turn ignition switch to ON position. Monitor TCC release pressure. If TCC release pressure is present, go to next step. If TCC release pressure is not present, go to step 5 .
4. Turn ignition off. Check for open in TCC release switch signal circuit between appropriate PCM connector and transaxle 20-pin harness connector. Repair as necessary. After repairs, go to step 11 . If TCC release switch signal circuit is okay, go to step 10 .
5. Check for open in TCC release switch signal circuit between transaxle 20-pin harness connector and PSA. If open is found, go to step 8 . If TCC release switch signal circuit is okay, go to step 9 .
6. Road test vehicle in 4th gear "D". Increase vehicle speed until TCC is applied. Ensure TCC slip speed is less than 40 RPM. If scan tool displays TCC release pressure is present, go to next step. If scan tool does not display TCC release pressure is present, see «DIAGNOSTIC AIDS»(/chevrolet/cavalier/iii-1995-2005/remont/automatic-trans/#automatic-transaxle-diagnosis-4t40-e-4t45-e) .
7. Inspect for leaking or cut torque converter "O" ring, blocked channel plate exhaust passage, leaking, cut or improperly installed oil pump bearing and seal assembly seal, valve body-to-spacer plate gasket misaligned, spacer plate-to-channel plate gasket misaligned, channel plate turbine shaft sleeve installed backward or does not fit, blocked valve body spacer plate release exhaust orifice, or cut or missing turbine shaft-to-sprocket seal. Repair component(s) as necessary. Go to step 11 .
8. Replace transaxle internal wiring harness. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
9. Replace PSA. See HYDRA-MATIC 4T40-E & 4T45-E OVERHAUL article. After repairs, go to step 11 .
10. Replace PCM. After replacement, program PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. After repairs, go to next step.
11. After repair is complete, select DTC on scan tool. Select CLEAR INFO function. Select SPECIFIC DTC and enter DTC "P1887". Drive vehicle in D4 to obtain 45 MPH. With TCC commanded on and engaged, TCC release pressure must not be present for 3 seconds. If DTC P1887 is not present, repair is complete. If DTC P1887 is still present, repeat test.

Inspect wiring for poor connections at PCM and transaxle 20-pin connector. Check for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside insulation. If diagnosing for intermittent short or open condition, move wiring harness while observing scan tool for value change.

NO MALFUNCTION INDICATOR LIGHT

If MIL does not illuminate, see MIL INOPERATIVE or MIL CIRCUIT CHECK under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

NO DATA LINK CONNECTOR DATA

If scan tool does not display PCM data, see DATA LINK CONNECTOR DIAGNOSIS OR NO SCAN TOOL DATA under SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

TRANSAXLE WIRING HARNESS CHECK

Note. For connector identification and component locations, refer to illustrations. (Scheme 109)and (Scheme 110).

1. Install Jumper Harness (J-39775) on transaxle 20-pin connector (transaxle harness side). Using DVOM and Connector Test Adapter Kit (J-35616), measure resistance between transaxle 20-pin connector terminals "A" and "E" (1-2 shift solenoid). If resistance is 24-31 ohms at 212°F (100°C) and 19-24 ohms at 68°F (20°C), go to step 3 . If resistance is not 24-31 ohms at 212°F (100°C) and 19-24 ohms at 68°F (20°C), go to next step.
2. Disconnect transaxle wiring harness connector at 1-2 shift solenoid. Measure resistance between 1-2 shift solenoid terminals. If resistance is not 24-31 ohms at 212°F (100°C) and 19-24 ohms at 68°F (20°C), replace 1-2 shift solenoid. If resistance is 24-31 ohms at 212°F (100°C) and 19-24 ohms at 68°F (20°C), go to step 14 .
3. Measure resistance between transaxle 20-pin connector terminals "B" and "E" (2-3 shift solenoid). If resistance is 24-31 ohms at 212°F (100°C) and 19-24 ohms at 68°F (20°C), go to step 5 . If resistance is not 24-31 ohms at 212°F (100°C) and 19-24 ohms at 68°F (20°C), go to next step.
4. Disconnect transaxle wiring harness connector at 2-3 shift solenoid. Measure resistance between 2-3 shift solenoid terminals. If resistance is not 24-31 ohms at 212°F (100°C) and 19-24 ohms at 68°F (20°C), replace 2-3 shift solenoid. If resistance is 24-31 ohms at 212°F (100°C) and 19-24 ohms at 68°F (20°C), go to step 14 .
5. Measure resistance between transaxle 20-pin connector terminals "E" and "T" (TCC PWM solenoid). If resistance is 13-15 ohms at 212°F (100°C) and 10-11 ohms at 68°F (20°C), go to step 7 . If resistance is not 13-15 ohms at 212°F (100°C) and 10-11 ohms at 68°F (20°C), go to next step.
6. Disconnect transaxle wiring harness connector at TCC PWM solenoid. Measure resistance between solenoid terminals. If resistance is not 13-15 ohms at 212°F (100°C) and 10-11 ohms at 68°F (20°C), replace TCC PWM solenoid. If resistance is 13-15 ohms at 212°F (100°C) and 10-11 ohms at 68°F (20°C), go to step 14 .
7. Measure resistance between transaxle 20-pin connector terminals "C" and "D" (pressure control solenoid). If resistance is 3-5 ohms at 212°F (100°C) and 4-7 ohms at 68°F (20°C), go to step 9 . If resistance is not 3-5 ohms at 212°F (100°C) and 4-7 ohms at 68°F (20°C), go to next step.
8. Disconnect transaxle wiring harness connector at pressure control solenoid. Measure resistance between solenoid terminals. If resistance is not 3-5 ohms at 212°F (100°C) and 4-7 ohms at 68°F (20°C), replace pressure control solenoid. If resistance is 3-5 ohms at 212°F (100°C) and 4-7 ohms at 68°F (20°C), go to step 14 .
9. Measure resistance between transaxle 20-pin connector terminals "S" and "V" (input speed sensor). If resistance is 750-835 ohms at 212°F (100°C) and 625-725 ohms at 68°F (20°C), go to step 11 . If resistance is not 750-835 ohms at 212°F (100°C) and 625-725 ohms at 68°F (20°C), go to next step.
10. Disconnect transaxle wiring harness connector at input speed sensor. Measure resistance between sensor terminals. If resistance is not 750-835 ohms at 212°F (100°C) and 625-725 ohms at 68°F (20°C), replace input speed sensor. If resistance is 750-835 ohms at 212°F (100°C) and 625-725 ohms at 68°F (20°C), go to step 14 .
11. Measure resistance between transaxle 20-pin connector terminals "L" and "M" (TFT sensor). If resistance is 164-190 ohms at 212°F (100°C) and 3106-3923 ohms at 68°F (20°C), go to step 13 . If resistance is not 164-190 ohms at 212°F (100°C) and 3106-3923 ohms at 68°F (20°C), go to next step.
12. Disconnect transaxle wiring harness connector at TFT sensor. TFT sensor is part of Transmission Fluid Pressure (TFP) manual valve position switch assembly. Measure resistance between sensor terminals. If resistance is not 164-190 ohms at 212°F (100°C) and 3106-3923 ohms at 68°F (20°C), replace TFT sensor. If resistance is 164-190 ohms at 212°F (100°C) and 3106-3923 ohms at 68°F (20°C), go to step 14 .
13. Using a DVOM and Connector Test Adapter Kit (J-35616), measure resistance between transaxle case and transaxle 20-pin connector terminals "A", "B", "C", "D", "E", "L", "M", "S", "T" and "V". If resistance is more than 250 k/ohms at terminals "A", "B", "C", "D", "E" and "T", 20 megohms at terminals "L" and "M" and 10 megohms at terminals "S" and "V", go to next step. If resistance is less than specified at each terminal, replace transaxle wiring harness.
14. Inspect for high resistance. Check transaxle wiring harness for poor electrical connections at 20-pin connector and at each component connector. Look for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Repair as necessary, then go to step 1 . If no problem was found with connections and terminals, replace transaxle wiring harness.

Note. Pressure Switch Assembly (pressure switch assembly) is also referred to as Transmission Fluid Pressure (TFP) manual valve position switch.

TRANSMISSION FLUID PRESSURE MANUAL VALVE POSITION SWITCH RESISTANCE CHECK

Note. For TFP manual valve position switch terminal identification, see WIRING DIAGRAMS .

1. Install Jumper Harness (J-39775) on transaxle 20-pin connector (transaxle harness side). Using a DVOM and Connector Test Adapter Kit (J-35616), measure resistance between transaxle 20-pin connector terminal "U" and transaxle case. (Scheme 109) If resistance is less than 50 ohms, go to step 3. If resistance is 50 ohms or more, go to next step.
2. Disconnect wiring harness connector at TFP manual valve position switch. (Scheme 110) Measure resistance between position switch terminal "D" and position switch housing. If resistance is less than 50 ohms, go to step 15. If resistance is 50 ohms or more, go to step 14.
3. Measure resistance between transaxle 20-pin connector terminal "N" and transaxle case. If resistance is more than 50 k/ohms, go to step 5. If resistance is 50 k/ohms or less, go to next step.
4. Disconnect wiring harness connector at TFP manual valve position switch. (Scheme 110) Measure resistance between TFP manual valve position switch terminal "A" and TFP manual valve position switch housing. If resistance is more than 50 k/ohms, go to step 15. If resistance is 50 k/ohms or less, go to step 14.
5. Measure resistance between transaxle 20-pin connector terminal "R" and transaxle case. If resistance is more than 50 k/ohms, go to step 7. If resistance is 50 k/ohms or less, go to next step.
6. Disconnect wiring harness connector at TFP manual valve position switch. Measure resistance between TFP manual valve position switch terminal "B" and TFP manual valve position switch housing. If resistance is more than 50 k/ohms, go to step 15. If resistance is 50 k/ohms or less, go to step 14.
7. Measure resistance between transaxle 20-pin connector terminal "P" and transaxle case. If resistance is more than 50 k/ohms, go to step 9. If resistance is 50 k/ohms or less, go to next step.
8. Disconnect wiring harness connector at TFP manual valve position switch. Measure resistance between TFP manual valve position switch terminal "C" and TFP manual valve position switch housing. If resistance is more than 50 k/ohms, go to step 15. If resistance is 50 k/ohms or less, go to step 14.
9. Start engine and let it idle. Set parking brake. Ensure selector lever is in "P" position. Measure resistance between transaxle 20-pin connector terminal "U" and transaxle case. If resistance is more than 50 k/ohms, go to next step. If resistance is 50 k/ohms or less, go to step 14.
10. Place selector lever in "R" position. Measure resistance between transaxle 20-pin connector terminal "P" and transaxle case. If resistance is less than 50 ohms, go to next step. If resistance is 50 ohms or more, go to step 14.
11. Place selector lever in "D" position. Measure resistance between transaxle 20-pin connector terminal "N" and transaxle case. If resistance is less than 50 ohms, measure resistance between transaxle 20-pin connector terminal "R" and transaxle case. If resistance is less than 50 ohms, go to next step. If resistance is 50 ohms or more, go to step 14.
12. Place selector lever in "1" position. Measure resistance between transaxle 20-pin connector terminal "N" and transaxle case. If resistance is less than 50 ohms, go to next step. If resistance is 50 ohms or more, replace TFP manual valve position switch.
13. Reconnect TFP manual valve position switch connector. Measure resistance between transaxle 20-pin connector terminal "P" and transaxle case. If resistance is less than 50 ohms, system is okay. If resistance is 50 ohms or more, go to next step.
14. Replace TFP manual valve position switch. After repairs, go to step 1.
15. Inspect for high resistance. Check transaxle wiring harness for poor electrical connections at 20-pin connector and at TFP manual valve position switch. Look for bent, backed out, deformed or damaged terminals. Check for weak terminal tension. Repair as necessary, then go to step 1. If no problem was found with connectors or terminals, replace transaxle wiring harness.

SHIFT SOLENOID LEAK TEST

Clamp 1/2" rubber hose over fluid inlet end of solenoid. Ground either terminal of solenoid. Apply less than 120 psi (8.4 kg/cm 2 ) to open end of rubber hose. Apply 12 volts to remaining terminal. If air leak exists when solenoid is energized, replace solenoid.

COMPONENT SPECIFICATIONS

TRANSAXLE COMPONENT RESISTANCE SPECIFICATIONS

Note. Before replacing PCM, carefully inspect all wiring and control components. Failure to test for short circuits may result in repeated PCM failure due to shorts. To prevent internal damage to PCM, ensure ignition switch is in OFF position when connecting or disconnecting PCM connectors or any electrical components.

Transmission Adaptive Pressure (TAP) values may need to be reset if one of the following repairs has been performed

1. Transaxle overhaul or replacement.
2. Repair or replacement of an apply or release component (band, clutch, piston and/or servo).
3. Repair or replacement of a component or assembly which directly affects transaxle line pressure.

To reset TAP values, see CLEARING & RESETTING TAP VALUES in DIAGNOSIS & TESTING.

Removal & Installation

Turn ignition off. Disconnect negative battery cable. Locate PCM. On "J" body models, PCM is located forward of right front wheel housing, behind front fascia cavity splash shield. On "N" body models, PCM is located below left side of instrument panel, near steering column. Remove any necessary components to gain access to PCM. Disconnect harness connectors from PCM. Remove PCM mounting bolts (if equipped). Remove PCM. To install, reverse removal procedure. Transfer any necessary components (i.e., knock sensor module, EEPROM, etc.) to NEW PCM before installation. Program replacement PCM using appropriate equipment and latest software. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

Transaxle Electronic Control System Wiring Diagram (Alero & Grand Am - 2.4L). Scheme 114

Transaxle Electronic Control System Wiring Diagram (Alero & Grand Am - 3.4L). Scheme 115

Transaxle Electronic Control System Wiring Diagram (Cavalier & Sunfire). Scheme 116

Transaxle Electronic Control System Wiring Diagram (Malibu). Scheme 117

Transaxle Electronic Control System Wiring Diagram (Saturn LS, LS1 & LW1). Scheme 118

See also:
• SOLENOID POSITIONS
• CLEARING & RESETTING TAP VALUES
• DIAGNOSIS & TESTING
• CLEARING DIAGNOSTIC TROUBLE CODES
• NO DATA LINK CONNECTOR DATA
• NO MALFUNCTION INDICATOR LIGHT
• DIAGNOSTIC TROUBLE CODE DEFINITIONS
• P0748
• P1810
• RETRIEVING DIAGNOSTIC TROUBLE CODES
• ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK