Diagnosis - CD4E: Other Ford Contour I

Air Conditioning Clutch (ACC)

On factory installed A/C system, PCM receives signal voltage from ACC switch indication that the air conditioning compressor clutch is engaged. The PCM uses the ACC switch signal to adjust line pressure to compensate for additional engine load. If the ACC switch fails with closed contacts, line pressure will be slightly low with air conditioning off. If the ACC switch fails with open contacts, line pressure will be slightly higher with air conditioning on.

Brake On/Off (BOO) Switch

The PCM receives a signal from the BOO switch when the brake switch is operated. Torque converter clutch is disengaged when brakes are applied. Malfunctioning switch will affect torque converter operation.

Crankshaft Position (CKP) Sensor & Ignition Control Module

(ICM)

The CKP sensor sends crankshaft position information to the ICM, which sends an engine speed signal to the PCM. Signal received by the PCM affects line pressure, shift scheduling, torque converter clutch and WOT shift control. Engine speed signal malfunction may result in harsh engagements, firm shifts, TCC lock-up and/or late WOT shifts.

Engine Coolant Temperature (ECT) Sensor

Engine temperature signal is sent to PCM. Malfunctioning ECT will affect torque converter clutch operation.

Mass Airflow Sensor (MAF)

The MAF signal is used for Electronic Pressure Control (EPC), shift and TCC operation and MAF malfunction will affect these areas.

Transmission Control Switch (TCS)

Switch is mounted on shift lever handle. Switch controls operation of 4th gear. Malfunction of switch will cause lack of 4th disable function.

Throttle Position Sensor (TPS)

The TPS is a potentiometer mounted to the engine throttle body. The PCM receives a signal from the TPS relaying throttle plate position. TPS failure will cause PCM to operate in fail safe mode and raise line pressure to prevent transaxle damage. This condition will result in harsh engagements, firm shift feel, abnormal shift schedule and TCC not engaging or cycling.

Transmission Range (TR) Sensor

The PCM monitors a series of step down resistors in the TR sensor that act as a voltage divider. The voltage signal corresponds with position of the transaxle range selector lever. The TR sensor also contains the neutral/start and backup light circuits. Malfunction of the TR sensor may cause harsh engagements and firm shift feel. Improper shifting or shift selection and no engine cranking may also result.

Transmission Speed Sensor (TSS)

The TSS is a magnetic pickup that sends turbine shaft speed signal to the PCM. Malfunction of sensor may cause harsh engagements of shifts. Lack of 4th gear or no engine braking in 2nd or 3rd gear may result.

Vehicle Speed Sensor (VSS)

The VSS is a magnetic pickup that sends output speed signal to the PCM. Malfunction of sensor may cause harsh engagements of shifts. Lack of 4th gear, TCC lock-up, or engine braking in 2nd or 3rd gear may result.

SERVICE CODE TYPES

During QUICK TEST, 3 types of service codes are retrieved: Key On Engine Off (KOEO), Key On Engine Running (KOER) and Continuous Memory codes. See QUICK TEST for self-test procedures. Codes may be cleared from PCM memory after they have been recorded or repaired. See CLEARING CODES .

KOEO & KOER Codes (Hard Faults)

These codes indicate faults are present at time of testing. A hard fault may cause CHECK ENGINE or Malfunction Indicator Light (MIL) to go on and remain on until fault is repaired. If KOEO or KOER codes are retrieved during KOEO SELF-TEST or KOER SELF-TEST, use CODE REFERENCE CHART to find correct testing and repair procedures.

Continuous Memory Codes (Soft Faults)

These codes indicate a fault that may or may not be present at time of testing. These codes are used to diagnose intermittent problems. Continuous Memory Codes are retrieved after KOEO SELF-TEST. Some codes may turn on MIL/CHECK ENGINE light. Corresponding soft fault trouble code will be retained in PCM memory. If fault does not reoccur within 40 warm-up cycles, PCM will automatically clear code.

Technician may clear service codes from memory. See CLEARING CODES . Intermittent faults may be caused by a sensor, connector or wiring-related problem.

RETRIEVING CODES

Note. Data Link Connector (DLC) was previously referred to as Self-Test connector or VIP connector.

Service codes are retrieved from EEC-IV system through Data Link Connector (DLC). Various methods and test equipment may be used to access these codes

1. Analog Volt-Ohmmeter (VOM)
2. Scan Tool
3. In-Dash Malfunction Indicator Light (MIL)/CHECK ENGINE light

Note. For engine-related DTCs information and testing, see the TESTS W/CODES - EEC-IV (2.0L) article in ENGINE PERFORMANCE. These DTCs pertain to engine performance and must be repaired first, as engine performance and related component signals will affect transmission operation and diagnosis.

Separator Pulse

Single 1/2-second separator pulse is issued 6-9 seconds after last KOEO code. Continuous Memory Codes (soft faults) are then displayed 6-9 seconds after 1/2-second separator pulse. Some digital test equipment may display separator code as "10" instead of "1".

Pass Codes

A Code 111 indicates no service codes were recorded in that portion of test; system passes that portion of test. If Code 111 is not retrieved in KOEO SELF-TEST, codes retrieved during KOER SELF-TEST may not be valid. Code 111 (pass code) must be obtained in KOEO SELF-TEST. A Code 111-1-111 output during KOEO SELF-TEST indicates no KOEO code or Continuous Memory Code was recorded.

Continuous Memory Codes

These codes result from information stored by PCM during continuous self-test monitoring. Codes are displayed after separator pulse code in KOEO SELF-TEST. Use these codes for diagnosis only when KOEO SELF-TEST and KOER SELF-TEST result in Code 111 (pass code) and all steps under QUICK TEST are successfully completed. These codes indicate faults recorded within last 40 engine starts (80 engine starts on some models). Fault may or may not be currently present. See CODE REFERENCE CHART .

Fast Codes

At start of KOEO SELF-TEST and after Wide Open Throttle (WOT) request in KOER SELF-TEST, PCM outputs short bursts of information, known as FAST CODES, which were used by manufacturer during assembly. With most equipment, these code bursts are not visible; an entire code sequence lasts less than 1/2 second. If this fluctuation is visible on test equipment, ignore it.

Scheme 54

CLEARING CODES

To clear codes from PCM memory, start KOEO SELF-TEST . When service codes appear on test equipment or CHECK ENGINE light, disconnect jumper wire from Self-Test Input (STI) connector. If using STAR Series Tester, unlatch center button. This procedure erases Continuous Memory Codes from PCM memory. If problem has not been corrected or fault is still present, hard code will immediately be reset in PCM memory.

ADDITIONAL SYSTEM FUNCTIONS

Additional diagnostic system features are available to help diagnose driveability problems and service EEC-IV systems.

Malfunction Indicator Light (MIL)

The MIL is intended to alert driver of certain malfunctions in EEC-IV system. Light may also be used to retrieve service codes stored in PCM. When hooked up for KOEO SELF-TEST or KOER SELF-TEST, light will display all codes which turn on light during vehicle operation.

Light should come on when ignition is turned on and go out when engine is started. If light comes on and then goes off during vehicle operation, code causing light to come on will be stored in PCM memory as a Continuous Memory Code. If light comes on during vehicle operation, vehicle should be inspected as soon as possible. Immediately turning off engine is not necessary; vehicle can be driven with light on.

Output State Check

Output State Check is used as an aid in servicing output actuators associated with EEC-IV system. It allows technicians to energize and de-energize most system output actuators on command. This mode is entered from KOEO SELF-TEST after all codes have been retrieved.

Disconnect cruise control servo (if equipped). With DVOM on 20-volt scale, connect DVOM negative lead to STO terminal at Diagnostic Link Connector (DLC). Connect positive lead to positive battery terminal. Using jumper wire, connect STI to SIG RTN at Diagnostic Link Connector (DLC).

Perform KOEO SELF-TEST until continuous memory test is complete. DVOM will read less than 1.0 volt when test is complete. Depress and release throttle. If voltage increases, OUTPUT STATE CHECK has been entered. If voltage does not increase, depress throttle to WOT and release. If STO voltage still does not increase, go to CIRCUIT TEST QC. See TESTS W/CODES - EEC-IV (2.0L) article in ENGINE PERFORMANCE.

Failure Mode Effects Management (FMEM), Code 998

FMEM mode allows system operation when sensors fail or transmit signals that are out of normal operating range. During FMEM mode, PCM substitutes a mid-range signal for defective sensor while continuing to monitor sensor. If faulty sensor's signals return to normal operating range, PCM will use those signals. A Code 98 or 998 will be displayed when FMEM mode is in effect.

EQUIPMENT HOOKUP

Complete all steps in PRELIMINARY INSPECTION before proceeding to self-diagnostic tests. Ensure vacuum hoses and EEC-IV wiring harnesses are properly connected. Apply parking brake, and place shift lever in Park (A/T) position. Block drive wheels. Turn off all electrical accessories. Connect appropriate test equipment to vehicle as follows

Analog Volt-Ohmmeter (VOM)

1. Turn ignition switch to OFF position. Set VOM at 0-15V DC range. Connect positive lead of VOM to positive battery terminal.
2. Connect negative VOM lead to Self-Test Output (STO) terminal of Data Link Connector (DLC). (Scheme 55) Activate KOEO SELF-TEST by connecting jumper wire from Self-Test Input (STI) pigtail to signal return terminal of Data Link Connector (DLC) with ignition on.

STAR Series Tester

Turn ignition switch to OFF position. Connect color-coded adapter cable leads to diagnostic tester. Connect 2 service connectors of adapter cable to vehicle Data Link Connector (DLC) and STI pigtail connector. Connect timing light. Go to KOEO SELF-TEST . Ensure tester is switched to fast mode.

Turn ignition on. Connect a jumper wire between Self-Test Input (STI) pigtail and signal return terminal of Data Link Connector (DLC). (Scheme 55) Go to KOEO SELF-TEST.

Scheme 55

Preliminary Set Up

Connect Transaxle Tester (007-0085C). Install pressure gauge to line pressure tap. See AUTO TRANS OVERHAUL - FORD CD4E TRANSAXLE article. Set Bench/Drive switch to DRIVE mode. Set tester to Gear Select "1" position. Ensure vehicle is in Park. Start vehicle.

EPC Solenoid

Record line pressure. Line pressure should be 76 psi (5.3 kg/cm 2 ) (maximum line pressure). If line pressure is not within specification, see TESTING in AUTO TRANS OVERHAUL - FORD CD4E TRANSAXLE article or PINPOINT TEST E. Depress EPC switch. Line pressure should be 64 psi (4.5 kg/cm 2 ) (minimum line pressure). If line pressure is not within specification, see TESTING in AUTO TRANS OVERHAUL - FORD CD4E TRANSAXLE article or PINPOINT TEST E.

Engagements

Rotate Gear Select switch to 3/R position. Shift transaxle from Park to Reverse. Reverse should engage. Shift transaxle from Reverse to Park. Rotate Gear Select switch to "1" position. Depress EPC switch. Line pressure should drop to idle pressure of 64 psi (4.5 kg/cm 2 ). While depressing EPC switch, shift vehicle from Park to Drive. Vehicle should shift into Drive with smooth engagement. Release EPC switch and repeat previous step. Vehicle shift engagement should be firm with EPC switch released.

Note. Ensure Gear Select switch is in 3/R position for reverse gear. Upshifts and downshifts will be firm during this procedure.

Upshift/Downshift

1. Remove line pressure gauge. Set gear select switch to 1st position. Shift transmission to drive. Depress the 3-2T/CCS button and accelerate (road test) vehicle. If vehicle will not move, forward one-way clutch failure is possible. If vehicle will move go to next step.
2. Ensure Gear Select switch is in "1" position. Shift transmission to overdrive and accelerate to 15 MPH. Rotate Gear Select switch to "2" position. Vehicle should shift into 2nd gear. Accelerate to 25 MPH and select "3" position. Vehicle should shift into 3rd gear. Accelerate to 35-45 MPH and select "4" position. Vehicle should shift into 4th gear.
3. Downshift as outlined in step 2). To prevent harsh 4-3 downshift depress 3-2T/CCS button during 4-3 downshift. Vehicle should downshift through each gear.

3-2 Timing/Coast Clutch Engagement

Accelerate and upshift vehicle into 3rd gear. Release throttle and depress 3-2T/CCS switch. Coast clutch should disengage. Lightly depress throttle and release 3-2T/CCS switch. Engine braking should occur.

Note. This test may be performed on hoist.

Transmission Speed Sensor Function Check

Set voltmeter to 20 volts A/C. Connect voltmeter leads to appropriate TSS jacks. Slowly accelerate vehicle and monitor voltmeter reading. Voltage should increase with vehicle speed.

SUMMARY

If no service code is present but driveability problem still exists, proceed to AUTO TRANS OVERHAUL - FORD CD4E TRANSAXLE article for symptom diagnosis procedures.

Note. CIRCUIT and PINPOINT TESTS are diagnostic formats used to test and service EEC-IV system. QUICK TEST allows technician to identify problems and retrieve service codes. CIRCUIT TESTS check engine circuits, sensors and actuators. PINPOINT TESTS check transaxle circuits, sensors and actuators.

CODE REFERENCE CHART

Note. For transmission fault codes perform appropriate circuit or pinpoint test. See CODE REFERENCE CHART table. For engine-related fault codes output during QUICK TEST procedure, see TESTS W/CODES - EEC-IV (2.0L) article in ENGINE PERFORMANCE section. These fault codes pertain to engine performance and must be repaired first as engine performance will greatly affect transmission operation.

Note. No trouble code was available for 3-2T/CCS component malfunction. If component is suspected, see PINPOINT TEST G .

CODE REFERENCE CHART

CIRCUIT TESTS

Note. A breakout box, connected to vehicle harness at PCM, is necessary to perform most circuit tests. References to Test Pin No. found in CIRCUIT TEST steps refer to test terminals on manufacturer's breakout box. Circuit diagrams at beginning of each test identify circuit and wire colors.

HOW TO USE CIRCUIT TESTS

1. DO NOT perform any CIRCUIT TEST unless specifically instructed by a «QUICK TEST»(ref-55818-S19164096512001033100000) procedure. Follow each test step in order until fault is found. DO NOT replace any part unless directed to do so. When more than one code is retrieved, start with first code displayed.
2. CIRCUIT TESTS ensure electrical circuits are okay before sensors or other components are replaced. Always test circuits for continuity between sensor and PCM. Test all circuits for short to power, opens or short to ground. Voltage Reference (VREF) and Voltage Power (VPWR) circuits should be tested with ignition on or as specified in CIRCUIT TESTS.
3. DO NOT measure voltage or resistance at PCM. DO NOT connect any test light unless specified in testing procedure. All measurements are made by probing rear of connector. Isolate both ends of a circuit and turn ignition off when checking for shorts or continuity, unless instructed otherwise.
4. Disconnect solenoids and switches from harness before measuring continuity and resistance or applying voltage. After each repair, check all component connections and repeat QUICK TEST.
5. An open circuit is defined as a resistance reading of greater than 5 ohms. This specification tolerance may be too high for some items in EEC-IV system. If resistance approaches 5 ohms, always clean suspect connector and coat it with protective dielectric silicone grease. A short is defined as a resistance reading of less than 10 k/ohms to ground, unless stated otherwise in CIRCUIT TEST.

Note. Procedures in CIRCUIT TESTS are written for the use of the following Ford Motor Co. test equipment: Super Star II Tester (007-0041B) Breakout Box (T83L-50-EEC-IV) Transaxle Tester (007-0085C)

Terminal pin references are based on this equipment and appropriate overlays. All references to "test pins", "test terminals" or "jacks" refer to test equipment. When aftermarket test equipment is used, always follow test equipment manufacturer's procedures.

PINPOINT TESTS

Note. Procedures in PINPOINT TESTS are written for the use of the following Ford Motor Co. test equipment: Super Star II Tester (007-0041B) Breakout Box (T83L-50-EEC-IV) Transaxle Tester (007-0085C)

Terminal pin references are based on this equipment and appropriate overlays. All references to "test pins", "test terminals" or "jacks" refer to test equipment. When aftermarket test equipment is used, always follow test equipment manufacturer's procedures.