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Automatic Transmission - 5l40-e (Diagnostic Information & Procedures) Cadillac CTS I

Automatic Trans ~1008 words

Diagnostic Starting Point - Automatic Transmission

Begin the system diagnosis with the Diagnostic System Check - Engine Controls in Engine Controls - 2.6L and 3.2L or Diagnostic System Check - Engine Controls in Engine Controls - 3.6L (LY7). The Diagnostic System Check - Engine Controls in Engine Controls - 2.6L and 3.2L or Diagnostic System Check - Engine Controls in Engine Controls - 3.6L (LY7) will provide the following information

  1. The identification of the control modules which command the system
  2. The ability of the control modules to communicate through the serial data circuit
  3. The identification of any stored diagnostic trouble codes (DTCs) and their status

The use of the Diagnostic System Check - Engine Controls in Engine Controls - 2.6L and 3.2L or Diagnostic System Check - Engine Controls in Engine Controls - 3.6L (LY7) will identify the correct procedure for diagnosing the system and where the procedure is located.

Description

IMPORTANTDo not perform the Diagnostic System Check-Automatic Transmission unless one of the concerns noted is present. Failure to follow this procedure could lead to misdiagnosis of the system.

The Diagnostic System Check-Automatic Transmission is an organized approach to identifying a condition created by an electronic transmission control system. The Diagnostic System Check-Automatic Transmission is intended for use in diagnosing a concern in a vehicle with separate engine and transmission control modules, ECM and TCM.

When an emission related diagnostic trouble code (DTC) sets as a result of a transmission fault, the TCM requests the ECM to illuminate the malfunction indicator lamp (MIL). This request will be identified by the ECM as DTC P0700. The ECM may also independently illuminate the MIL. Although either module may cause the MIL to illuminate, the scan tool can display DTCs from only one module at a time. In addition, the Clear DTC Info command clears DTC data from both modules. If the DTC failure records are not recorded from both modules before the DTC data is cleared, important diagnostic information will be erased.

Your training and experience as a technician may cause you to focus on either the TCM or the ECM, instead of both modules at the same time. To ensure that both modules are properly diagnosed, separate system checks are included. The Diagnostic System Check - Engine Controls in Engine Controls - 2.6L and 3.2L or Diagnostic System Check - Engine Controls in Engine Controls - 3.6L identifies DTC status and communication function for the ECM. If no ECM DTCs are present, the Diagnostic System Check - Engine Controls in Engine Controls - 2.6L and 3.2L or Diagnostic System Check - Engine Controls in Engine Controls - 3.6L will direct you to the Diagnostic System Check-Automatic Transmission.

The ECM diagnostics do not require transmission data in order to run. Correct use of the tables will reduce diagnostic time and prevent the replacement of good parts.

Diagnostic Aids

Inspect all of the related wiring and connections including the connections at the TCM, as these may cause an intermittent concern. Inspect the terminals for any damage or any corrosion. Inspect the connector for any pushed-out terminals.

StepActionYesNo
1Perform the following preliminary inspections: Ensure that the battery is fully charged. Refer to Battery Inspection/Test in Engine Electrical. Ensure that the battery cables are clean and tight. Inspect the easily accessible systems of the visible system components for obvious damage or conditions that could cause the symptom. Refer to Strategy Based Diagnosis in General Information. Ensure that the engine and control module grounds are clean, tight, and in the correct location. Inspect for aftermarket devices that could affect the operation of the system. Refer to Checking Aftermarket Accessories in Wiring Systems. Ensure the resistance between the TCM housing and the battery negative cable is less than 0.5 ohm. Did you find and correct the condition?System OKGo to Step 2
2Turn ON the ignition, with the engine OFF. Attempt to establish communication with the listed control modules: Transmission control module (TCM) Engine control module (ECM) Electronic brake control module (EBCM) Instrument panel cluster (IPC) HVAC control module Theft deterrent control module Does the scan tool communicate with all the listed control modules?Go to Step 3Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications
3IMPORTANT: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode. Access the Class 2 Power Mode in the Diagnostic Circuit Check on the scan tool. Rotate the ignition switch through all positions while observing the ignition switch power mode parameter. Refer to Body Control System Description and Operation in Body Control Systems for a list of the power mode states that correspond to each ignition switch position. Does the ignition switch parameter reading match the ignition switch position for all switch positions?Go to Step 4Go to Power Mode Mismatch in Body Control System
4Attempt to start the engine. Does the engine crank?Go to Step 5Go to Symptoms - Engine Electrical in Engine Electrical
5Did the engine start and idle?Go to Step 6Go to Engine Cranks but Does Not Run in Engine Controls - 2.6 and 3.2L or Engine Cranks but Does Not Run in Engine Controls - 3.6L
6IMPORTANT: Do NOT clear the DTCs unless instructed by a diagnostic procedure. Select the DTC display function for the following control modules and record the DTCs: Transmission control module (TCM) Engine control module (ECM) Electronic brake control module (EBCM) Instrument panel cluster (IPC) HVAC control module Theft deterrent control module IF multiple powertrain DTCs are stored, diagnose the DTCs in the following order: Test for component lever DTCs. For example, sensor DTCs, then solenoid DTCs. Begin with the lowest number DTC unless the diagnostic table directs you otherwise. If there is any powertrain DTCs, Select Capture Info in order to store the Powertrain DTC information with a scan tool. Does the scan tool display any DTCs?Go to Step 7Go to Step 10
7Does the scan tool display DTCs which begin with a "U"?Go to Diagnostic Trouble Code (DTC) List in Data Link CommunicationsGo to Step 8
8Does the scan tool display DTC P0601, P0602, P0603, P0604 or P1621?Go to DTC P0601 , DTC P0602 , DTC P0603 , DTC P0604 or DTC P1621Go to Step 9
9Does the scan tool display DTC P0562 or P0563?Go to DTC P0562 or DTC P0563Go to Step 10
10Are there any other TCM DTCs observed?Go to Diagnostic Trouble Code (DTC) List/TypeGo to Step 11
11Are there any ECM DTCs or driveability symptoms other than DTC P0700 observed?Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 2.6L and 3.2L or Diagnostic Trouble Code (DTC) List in Engine Controls - 3.6LGo to Step 12
12Are there any transmission controls or transmission driveability symptoms observed?Go to Symptoms - Automatic TransmissionSystem OK
IMPORTANT
The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode.
IMPORTANT
Do NOT clear the DTCs unless instructed by a diagnostic procedure.

Diagnostic System Check - Automatic Transmission

Scan Tool Output Controls (add on)

Scan Tool Output ControlAdditional Menu Selection(s)Description
1- 2 SolenoidThe TCM commands the 1-2 shift solenoid valve ON and OFF. The scan tool 1-2 Sol. parameter should match the commanded state. The scan tool Commanded Gear parameter should correspond with the shift solenoid combination. Refer to Shift Solenoid Valve State and Gear Ratio . When the ignition is ON, and the engine is OFF, there are no limits to this control. The solenoid remains ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the TCM. When the engine is running, the following control limits apply: Only sequential gear changes are allowed. For example, 1st to 3rd is not allowed. If a non-sequential gear change is attempted, the message "Non-sequential gear changes not allowed. Gear changes must be in order" appears on the scan tool display. The vehicle speed must be below a calibrated value. If the vehicle speed is too high, the message "Vehicle speed too high" appears on the scan tool display. The engine speed must be below a calibrated value. If the engine speed is too high, the message "Engine speed too high" appears on the scan tool display. Downshifts are allowed only when the vehicle speed is below a calibrated value. If the vehicle speed is too high, the message "Eng. is on and veh. speed too hi for 3-2 or 2-1 downshift" appears on the scan tool display. The gear requested may not be greater than the current selected transmission range. For example, 3rd gear is not allowed if the transmission range is D2. If the gear requested is greater than the current selected transmission range, the message "Eng. running and gear request is greater than the current TR" appears on the scan tool display. The solenoid remains ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the TCM.
2- 3 SolenoidThe TCM commands the 2-3 shift solenoid valve ON and OFF. The scan tool 2-3 Sol. parameter should match the commanded state. The scan tool Commanded Gear parameter should correspond with the shift solenoid combination. Refer to Shift Solenoid Valve State and Gear Ratio . When the ignition is ON, and the engine is OFF, there are no limits to this control. The solenoid will remain ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the TCM. When the engine is running, the following control limits apply: Only sequential gear changes are allowed. For example, 1st to 3rd is not allowed. If a non-sequential gear change is attempted, the message "Non-sequential gear changes not allowed. Gear changes must be in order" appears on the scan tool display. The vehicle speed must be below a calibrated value. If the vehicle speed is too high, the message "Vehicle speed too high" appears on the scan tool display. The engine speed must be below a calibrated value. If the engine speed is too high, the message "Engine speed too high" appears on the scan tool display. Downshifts are allowed only when the vehicle speed is below a calibrated value. If the vehicle speed is too high, the message "Eng. is on and veh. speed too hi for 3-2 or 2-1 downshift" appears on the scan tool display. The gear requested may not be greater than the current selected transmission range. For example, 3rd gear is not allowed if the transmission range is D2. If the gear requested is greater than the current selected transmission range, the message "Eng. running and gear request is greater than the current TR" appears on the scan tool display. The solenoid remains ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the TCM.
4- 5 SolenoidThe TCM commands the 4-5 shift solenoid valve ON and OFF. The scan tool 4-5 Sol. parameter should match the commanded state. The scan tool Commanded Gear parameter should correspond with the shift solenoid combination. Refer to Shift Solenoid Valve State and Gear Ratio . When the ignition is ON, and the engine is OFF, there are no limits to this control. The solenoid will remain ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the TCM. When the engine is running, the following control limits apply: Only sequential gear changes are allowed. For example, 1st to 3rd is not allowed. If a non-sequential gear change is attempted, the message "Non-sequential gear changes not allowed. Gear changes must be in order" appears on the scan tool display. The vehicle speed must be below a calibrated value. If the vehicle speed is too high, the message "Vehicle speed too high" appears on the scan tool display. The engine speed must be below a calibrated value. If the engine speed is too high, the message "Engine speed too high" appears on the scan tool display. Downshifts are allowed only when the vehicle speed is below a calibrated value. If the vehicle speed is too high, the message "Eng. is on and veh. speed too hi for 3-2 or 2-1 downshift" appears on the scan tool display. The gear requested may not be greater than the current selected transmission range. For example, 3rd gear is not allowed if the transmission range is D2. If the gear requested is greater than the current selected transmission range, the message "Eng. running and gear request is greater than the current TR" appears on the scan tool display. The solenoid remains ON until commanded OFF, and vice versa. When the output control is exited, the solenoid state is determined by the TCM.
Reset Transmission AdaptsThe TCM clears, or resets, all TAP cells to zero. There are no limits to using this control. It may be performed with the engine running or when the ignition is ON, and the engine is OFF.
PC SolenoidThe TCM commands the amperage to the pressure control solenoid in order to control transmission line pressure. As the amperage increases, the line pressure decreases. As the amperage decreases, the line pressure increases. The amperage range is 0.10-1.10 and may be commanded in one-tenth amp increments. When the ignition is ON, and the engine is OFF, the reference, commanded, amperage may be controlled within calibrated limits. The scan tool parameter "PC Sol. Ref. Current" changes, but the parameter "PC Sol. Actual Current" does not change. The reference current remains until commanded otherwise. When the engine is running, the following control limits apply: When the transmission range is Park or Neutral, the reference, commanded, amperage may be controlled within calibrated limits. The engine speed must be less than 1,500 RPM. If the engine speed is greater than 1,500 RPM, the message "TR in park/neutral and engine speed over 1,500 RPM" appears on the scan tool display. Both the scan tool parameters "PC Sol. Ref. Current" and "PC Sol. Actual Current" change. Both current readings remain until commanded otherwise. When the transmission range is not in Park or Neutral, the reference amperage can only be controlled less than the current determined by the TCM. The TCM does not allow a value to be selected that may cause damage to the transmission. If the requested amperage is more than allowed by the TCM, the message "Requested current for the PC Solenoid is too high" appears on the scan tool display. Transmission IMS DTCs must not be active. If a transmission IMS DTC is active, the message "Engine running with transmission DTC present" appears on the scan tool display.
Shift TransmissionThe TCM commands upshifts and downshifts. The scan tool Commanded Gear parameter should correspond with the shift solenoid combination. Refer to Shift Solenoid Valve State and Gear Ratio . When the ignition is ON, and the engine is OFF, there are no limits to this control. The scan tool shift solenoid states change to match the Commanded Gear selected. When the engine is running, the following control limits apply: The TCM does not allow a shift if it causes the engine RPM to exceed a calibrated limit. If a gear is requested and the engine speed is too high, the message "Engine speed too high" appears on the scan tool display. The TCM does not allow a 3-2 or 2-1 downshift if the vehicle speed exceeds a calibrated limit. If either downshift is requested and the vehicle speed is too high, the message "Eng. is on and veh. speed too hi for 3-2 or 2-1 downshift" appears on the scan tool display. The TCM does not allow a 4-3 downshift if the vehicle speed exceeds a calibrated limit. If a 4-3 downshift is requested and the vehicle speed is too high, the message "Vehicle speed too high" appears on the scan tool display. The TCM does not allow an upshift if the vehicle speed exceeds a calibrated limit. If an upshift is requested and the vehicle speed is too high, the message "Vehicle speed too high" appears on the scan tool display. The TCM does not allow an upshift that is greater than the current selected transmission range. For example 3rd gear is not allowed if the transmission range is D2. If an upshift is requested that is greater than the current selected transmission range, the message "Eng. running and gear request is greater than the current TR" appears on the scan tool display.
TCC Control SolenoidThe TCM commands the duty cycle of the TCC PWM solenoid. The duty cycle is represented by a percentage of ON, energized, time. Approximately 90-100 percent duty cycle represents an ON, energized, commanded state. Zero percent represents an OFF, non-energized, commanded state. The scan tool TCC Duty Cycle parameter should match the commanded state. When the ignition is ON, and the engine is OFF, there are no limits to this control. The solenoid remains ON, 90-100 percent duty cycle until commanded OFF, zero percent duty cycle, and vice versa. When the output control is exited, the solenoid duty cycle is determined by the TCM. When the engine is running, the following control limits apply: If the transmission range is Park, and the transmission is in hot mode, the TCC control solenoid may not be commanded OFF. If the solenoid is requested OFF, the message "TCC OFF command disabled in Hot Mode" appears on the scan tool display. The TCC control solenoid may not be commanded OFF for more than a calibrated amount of time. If the solenoid is commanded OFF, for a certain amount of time, the message "TCC OFF time has been exceeded" appears on the scan tool display.
High Side Driver 1The TCM commands the driver for the solenoid voltage supply ON and OFF. When the ignition is ON, and the engine is OFF, there are no limits to this control. High side driver 1 may not be commanded ON and OFF with the scan tool if the engine is running.
High Side Driver 2The TCM commands the driver for the solenoid voltage supply ON and OFF. When the ignition is ON, and the engine is OFF, there are no limits to this control. High side driver 2 may not be commanded ON and OFF with the scan tool if the engine is running.

Scan Tool Output Controls (add on)

Scan Tool Data List

Use the Scan Tool Data List under the following conditions

  1. The «Diagnostic System Check - Automatic Transmission»(/cadillac/cts/i-2002-2007/remont/automatic-trans/#automatic-transmission-5l40-e-diagnostic-information-procedures) has been completed
  2. The On-Board Diagnostics are functioning properly
  3. No DTCs are present
IMPORTANTDo not use a scan tool that displays faulty data. Report the condition to the scan tool manufacturer. The use of a faulty scan tool can result in misdiagnosis and the unnecessary replacement of parts.

Only the parameters listed below are used in this service manual for diagnosing. If a scan tool displays other parameters, the values are not recommended by General Motors for use in diagnosis.

Scan tool values below were recorded under the following conditions

  1. Engine at idle
  2. Upper radiator hose is hot
  3. Closed throttle
  4. Transmission in PARK
  5. Closed loop operation
  6. Accessories OFF
  7. Brake pedal not applied
Scan Tool ParameterData List*Units DisplayedTypical Data Value
1-2 Shift ErrorF2SecondsVaries
1-2 Shift TimeF0, F2SecondsVaries
1-2 Sol.F0, F2, F3, F4, F5On/OffOff
1-2 Sol. CKT StatusF2OK/Short to Volts/Open/SHT GND.OK
1-2 TAP Cell (4-16)F7/F0KPa (psi)Varies
2-3 Shift ErrorF3SecondsVaries
2-3 Shift TimeF0, F3SecondsVaries
2-3 Sol.F0, F2, F3, F4, F5On/OffOn
2-3 Sol. CKT StatusF3OK/Short to Volts/Open/SHT GND.OK
2-3 TAP Cell (4-16)F7/F1KPa (psi)Varies
3-4 Shift ErrorF4SecondsVaries
3-4 Shift TimeF0, F4SecondsVaries
3-4 TAP Cell (4-16)F7/F2KPa (psi)Varies
4-5 Shift ErrorF5SecondsVaries
4-5 Shift TimeF0, F5SecondsVaries
4-5 Sol.F0, F2, F3, F4, F5On/OffOff
4-5 Sol. CKT StatusF5OK/Short to Volts/Open/SHT GND.OK
4-5 TAP Cell (4-16)F7/F3KPa (psi)Varies
A/C ClutchF0On/OffOff
Commanded GearF0, F1, F2, F3, F4, F5, F61,2,3,4,51
CruiseF0Enabled/DisabledDisabled
ECTF0, F1°C (°F)85-115°C (185-239°F)
Engine SpeedF0, F1, F2, F3, F4, F5, F6RPM650-800 RPM
Engine TorqueF0, F1N.m (lb ft)0-13 N.m (lb ft)
Gear RatioF0, F1, F2, F3, F4, F5RatioVaries
High Side Driver 1F6Enabled/DisabledEnabled
High Side Driver 1 CKT StatusF6OK, Open/Short to Volts, Short to GNDOK
High Side Driver 2F1, F2, F3, F5Enabled/DisabledEnabled
High Side Driver 2 CKT StatusF1, F2, F3, F5OK, Open/Short to Volts, Short to GNDOK
Ignition VoltageF0Volts12.0-14.7 Volts
IMS A/B/C/PF0HI/LOWHigh/Low/Low/High
IMSF0Park, Park/Reverse, Reverse, Reverse/Neutral, Neutral, Neutral/Drive 5, Drive 5, Drive 5/Drive 4, Drive 4, Drive 4/Drive 3, Drive 3, Drive 3/Drive 2, Drive 2, InvalidPark
Last Shift TimeF0SecondsVaries
PC Sol. Actual CurrentF0, F6AmpsVaries
PC Solenoid Duty CycleF0, F6%Varies
PC Sol. Ref. CurrentF0, F6AmpsVaries
Steady State TAP 1 GRF7/F4KPa (psi)Varies
Steady State TAP 1 GR/TCCF7/F4KPa (psi)Varies
Steady State TAP 2 GRF7/F4KPa (psi)Varies
Steady State TAP 2 GR/TCCF7/F4KPa (psi)Varies
Steady State TAP 3 GRF7/F4KPa (psi)Varies
Steady State TAP 3 GR/TCCF7/F4KPa (psi)Varies
Steady State TAP 4 GRF7/F4KPa (psi)Varies
Steady State TAP 4 GR/TCCF7/F4KPa (psi)Varies
Steady State TAP 5 GRF7/F4KPa (psi)Varies
Steady State TAP 5 GR/TCCF7/F4KPa (psi)Varies
Steady State TAP ReverseF7/F4KPa (psi)Varies
TCC Brake SwitchF0, F1On/OffOff
TCC Duty CycleF0, F1%0%
TCC Duty Cycle CKT StatusF1OK/Short to Volts/Open/SHT GND.OK
TCC Slip SpeedF0, F1RPM0 RPM
TP AngleF0, F1, F2, F3, F4, F5, F6%0
Traction ControlF0Active/InactiveInactive
Trans. Fluid Temp.F0, F1, F6°C (°F)85-110°C (185-239°F)
Transmission Hot ModeF0, F1On/OffOff
Transmission ISSF0, F1, F2, F3, F4, F5RPM650-800 RPM
Transmission OSSF0, F1, F2, F3, F4, F5RPM0 RPM
Vehicle SpeedF0, F1, F2, F3, F4, F5Km/h (mph)0 km/h (0 mph)
*Data List Legend F0: Transmission Data F1: TCC Data F2: 1-2 Shift Data F3: 2-3 Shift Data F4: 3-4 Shift Data F5: 4-5 Shift Data F6: PC Solenoid Data F7/F0: Transmission Adapts/1-2 Adapt. Data F7/F1: Transmission Adapts/2-3 Adapt. Data F7/F2: Transmission Adapts/3-4 Adapt. Data F7/F3: Transmission Adapts/4-5 Adapt. Data F7/F4: Transmission Adapts/Steady State Data

Scan Tool Data List

Scan Tool Data Definitions

This list explains each data message displayed on the scan tool. This information will assist you in tracking down emissions or driveability DTCs, because you can view the displays while you are driving the vehicle. Refer to Diagnostic System Check - Automatic Transmission for additional information.

Diagnostic Trouble Code (DTC) Type Definitions

Diagnostic Trouble Codes (DTCs) are grouped into several types. Each type has a unique set of characteristics for MIL operation, DTC storage, and DTC clearing. The following list contains a brief summary of the DTC types and the associated properties of each.

Type A

This DTC is emissions related. The MIL illuminates and default actions, if any, are activated immediately after a failure is detected. The DTC is then stored in history and the Freeze Frame data is captured.

Type B

This DTC is emissions related. Default actions, if any, are activated and a Failure Record is stored after the first failure is detected. At the time of the first fail, the DTC will appear in memory as pending. If the next trip reports a pass, the pending DTC is deleted. If the failure recurs on the next consecutive drive cycle, the MIL illuminates, the DTC is stored in history, and the Freeze Frame data is captured at the time of failure.

Type C

This DTC is non emission related and does not turn on the MIL. When a Type C DTC sets, a message may be displayed on the driver information center. Type C DTCs that do not display a message were formerly referred to as type D DTCs.

Diagnostic Trouble Code (DTC) List/Type

Diagnostic Trouble Code (DTC) List/Type