Engine Controls - Tests W/codes - Eec (1.8L): Other Ford Escort V facelift

Hard Failures

Hard failures cause Malfunction Indicator Light (MIL) to come on and trouble codes to be set in Powertrain Control Module (PCM) memory. Trouble code remains until problem is repaired. To retrieve trouble codes, see RETRIEVING CODES. Use circuit tests to determine cause of malfunction.

If a sensor fails, PCM will use a substitute value in its calculations to continue engine operation. PCM can estimate failed sensor values based on feedback from working sensors. In this condition, known as Limited Operating Strategy (LOS), vehicle runs but driveability will not be optimum.

Intermittent Failures

Intermittent failures may cause Malfunction Indicator Light (MIL) to flicker or glow. Light will go out after intermittent fault goes away. These faults indicate that a defect may or may not be present at time of testing; however, corresponding trouble code will be retained in PCM memory.

If related fault does not reoccur within a certain time frame, trouble code will be erased from PCM memory. Intermittent failures may be caused by a sensor, connector or wiring problems. See INTERMITTENTS in H - EEC TESTS W/O CODES article in this section.

RETRIEVING CODES

Retrieve codes from EEC system through Data Link Connector (DLC) using following self-test procedures: Key On Engine Off (KOEO) and Key On Engine Running (KOER). See QUICK TEST. If no code or only intermittent fault is found after performing KOEO and KOER self-tests, proceed to SWITCH MONITOR TEST.

Note. Before hooking up equipment to diagnose EEC system, prepare and visually inspect vehicle. See VISUAL CHECK & VEHICLE PREPARATION.

Visual Check & Vehicle Preparation

Before hooking up any equipment to diagnose EEC system, visually check following and perform preparation procedures

1. Check condition of air cleaner and air ducting.
2. Perform all necessary safety precautions to prevent personal injury or vehicle damage.
3. Block drive wheels. Set parking brake. Place shift lever in Park(A/T) or Neutral (M/T). DO NOT move shift lever during test unless specifically directed to do so.
4. Check all vacuum hoses for leaks, restrictions and proper routing.
5. Check EEC system wiring harness connections for corrosion, damaged pins, loose wires and improper routing.
6. Check PCM, sensors and actuators for physical damage.
7. Check engine coolant and oil level.
8. Turn off all lights and accessories. Ensure vehicle doors are closed when measuring voltage or resistance.
9. Start engine, and allow it to idle until upper radiator hose is hot and pressurized. Check for leaks around exhaust manifold and exhaust gas oxygen sensor.

Key On Engine Off (KOEO) & Key On Engine Running (KOER)

Self-Tests

Perform KOEO and KOER self-test procedures using either Analog Volt-Ohmmeter (VOM), Malfunction Indicator Light (MIL) or Super Star II tester.

Note. EEC system will not display a PASS code.

KOEO codes include hard and intermittent failures. To determine failure type (hard or intermittent), record and clear codes stored in PCM memory. Operate vehicle, and repeat KOEO self-test. Codes that reappear immediately are hard failures. Codes that do not reappear are intermittent failures.

Repair hard failures in order of code appearance before performing KOER self-test. Use appropriate CODE REFERENCE CHART table to determine circuit test to perform. Clear codes from PCM memory after they have been recorded and/or faults have been repaired. See CLEARING CODES. If no trouble codes are found during KOEO self-test, proceed to KOER self-test.

Analog Volt-Ohmmeter (VOM)

1) Turn ignition off. To initiate KOEO self-test, connect a jumper wire between PCM STI terminal of Data Link Connector (DLC) and ground. (Scheme 171)

2) Set VOM to 0-20V DC range. Connect positive (+) lead of VOM to PCM STO terminal at DLC and negative (-) test lead to engine ground.

3) Turn ignition on and observe voltmeter. Count voltmeter needle sweeps (between 0-12 volts) to determine code. (Scheme 170)

Scheme 170

Scheme 171

4) If codes are not present, go to step 6). If codes are present, record codes. Turn ignition off, and go to next step.

5) Erase codes from PCM memory. See CLEARING CODES. Repeat step 3) to identify hard faults. If code does not reappear, fault is intermittent. Go to step 8) to begin KOER self-test. If code reappears, indicating hard fault, repair fault as necessary. Refer to appropriate CODE REFERENCE CHART to determine circuit test to perform. Go to step 7).

6) If engine starts, go to step 8) to begin KOER self-test. If engine does not start, go to appropriate BASIC TESTING article in this section.

7) Repeat step 5) until no code appears. Terminate KOEO self-test by turning ignition off and disconnecting jumper wire from PCM STI terminal and ground. Go to next step to begin KOER self-test.

8) Start and operate engine at 2000 RPM for 3 minutes to ensure HO2S/O2S sensor is operating. Ensure vehicle is at normal operating temperature. Turn ignition off. Jumper PCM STI terminal to ground to activate KOER self-test. Turn ignition on, and wait 10 seconds.

9) Start engine and allow it to idle. Ensure VOM is connected as described in step 2). Record all codes displayed, and repair fault as necessary. Refer to appropriate CODE REFERENCE CHART to determine circuit test to perform. If no code is present, go to ANALOG VOLT-OHMMETER (VOM) under SWITCH MONITOR TEST.

Malfunction Indicator Light (MIL)

1) Check MIL operation. Turn ignition on. If MIL is on, MIL circuit is okay. Go to next step. If MIL is off, go to TEST MIL. After performing TEST MIL, return to this procedure.

2) Connect a jumper wire between ground and PCM STI terminal of Data Link Connector (DLC). (Scheme 171) Turn ignition on. Observe MIL and record pulses to determine KOEO codes stored.

Note. Reading codes using MIL pulses is similar to reading codes using VOM needle sweeps. See ANALOG VOLT-OHMMETER (VOM) under QUICK TEST.

3) If codes are not present, go to next step. If codes are present, go to step 5).

4) If engine starts, go to step 7) to begin KOER self-test. If engine does not start, go to the BASIC TESTING article in this section.

5) Erase codes from PCM memory. See CLEARING CODES. Repeat step 2) to identify hard faults. If code does not reappear, fault is intermittent. Go to step 7) to begin KOER self-test. If code reappears, indicating hard fault, repair fault as necessary. See appropriate CODE REFERENCE CHART to determine circuit test to perform. Go to next step.

6) Repeat step 5) until no code appears. Terminate KOEO self-test by turning ignition off and disconnecting jumper wire from PCM STI terminal. Go to next step to begin KOER self-test.

7) Start and operate engine at 2000 RPM for 3 minutes to ensure HO2S/O2S sensor is operating. Ensure vehicle is at normal operating temperature. Connect jumper wire between ground and PCM STI terminal of DLC. Observe MIL. Record pulses to determine KOER codes stored. Use appropriate CODE REFERENCE CHART to determine circuit test to perform.

Super Star II Tester

1) To initiate KOEO self-test, turn ignition off. Connect color-coded adapter cable leads to Super Star II tester. Connect service adapter cables to vehicle Data Link Connector (DLC).

2) Use Harness Adapter (007-00049 or 007-0052) between adapter cables and vehicle DLC. Slide adapter switch to EEC/MECS position. Slide Super Star II tester switch to EEC/MECS position.

3) Set center button in TEST position. Turn Super Star II tester on. Tester should display 888 for 2 seconds when activated. Turn ignition on.

4) Release and then reset button in TEST position. After all codes have been received by tester, release center button.

5) Retrieve and record all codes in tester memory, and then go to next step. If no code exists, go to step 7).

6) Erase codes from PCM memory. See CLEARING CODES. Repeat steps 3) and 4) to identify hard faults. If code does not reappear, fault is intermittent. Go to step 9) to begin KOER self-test. If code reappears, indicating hard fault, repair fault as necessary. See the CODE-TO-TEST MENU to determine circuit test to perform. Go to step 8).

7) If engine starts, go to step 9) to begin KOER self-test. If engine does not start, go to appropriate BASIC TESTING article in this section.

8) Repeat step 6) until no code appears. Turn ignition off. Go to next step to begin KOER self-test.

9) To initiate KOER self-test, ensure center button on Super Star II tester is unlatched and turned to OFF position. Start and operate engine at 2000 RPM for 3 minutes to ensure HO2S/O2S sensor is operating. Turn Super Star II tester on. Set center button in TEST position. Turn ignition off. Start engine and allow it to idle.

10) To activate KOER self-test, release and then reset button in TEST position. Record all codes displayed. Refer to appropriate CODE REFERENCE CHART to determine circuit test to perform. If no code is displayed, go to SUPER STAR II TESTER under SWITCH MONITOR TEST.

1) Turn engine off and allow it to cool. Turn all accessories off. Disconnect PCM STI jumper from ground. Place shift lever in Park (A/T) or Neutral (M/T).

2) Reconnect jumper wire between ground and PCM STI terminal at DLC connector. Using VOM, connect positive (+) lead to SML terminal at DLC connector. Connect negative (-) lead to engine ground.

3) Turn ignition on. Test EEC input devices individually. See SWITCH MONITOR TEST SPECIFICATIONS table. Ensure input device is deactivated after test. Leaving device on while testing another device may produce false results and cause misdiagnosis.

4) If input device fails test (reading on VOM is not as indicated), perform related circuit test. See SWITCH MONITOR TEST SPECIFICATIONS table. If all input devices fail, check Switch Monitor Light (SML) circuit. See TEST SML. If all input devices test okay and no code is stored in PCM memory, EEC system test is complete.

SWITCH MONITOR TEST SPECIFICATIONS

1) Turn engine off and allow it to cool. Turn all accessories off. Connect tester. See SUPER STAR II TESTER under QUICK TEST. Ensure tester center button is released.

2) Place shift lever in Park (A/T) or Neutral (M/T). Turn tester on, and set center button to TEST position. Observe LED indication as each input device is tested. See SWITCH MONITOR TEST SPECIFICATIONS table.

3) Test EEC input devices individually. Turn device off after test. Leaving device on while testing another device may produce false results and cause misdiagnosis. If input device fails test (reading on Super Star II tester is not as indicated), perform related circuit test. See SWITCH MONITOR TEST SPECIFICATIONS table.

4) If all input devices fail, check Switch Monitor Light (SML) circuit. See TEST SML. If all input devices test okay and no code is stored in PCM memory, EEC system test is complete.

CLEARING CODES

To clear trouble codes, deactivate self-test by disconnecting jumper wire from PCM STI terminal at Data Link Connector (DLC). Disconnect negative (-) battery cable. Depress brake pedal for 5-10 seconds. All hard codes and intermittent codes will be erased from PCM memory.

SUMMARY

If no hard fault codes are present, driveability symptoms exist or intermittent codes exist, proceed to H - EEC TESTS W/O CODES article in this section for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.

CIRCUIT TESTS

Note. For identification of PCM connector terminals (Scheme 172)

Scheme 172

HOW TO USE CIRCUIT TESTS

1) DO NOT perform any circuit test unless specifically instructed by a procedure under QUICK TEST or SWITCH MONITOR TEST. Ensure all non-EEC related faults are corrected. Follow each test step in order until fault is found. When more than one code is received, start with first code displayed.

2) Use circuit tests to check electrical circuits before replacing sensors or any other components. Always test circuits for continuity between sensor and PCM. Test all circuits for short to power, opens or short to ground.

Note. A short is defined as a resistance value of less than 5 ohms.

3) DO NOT connect any test light or measure voltage or resistance at PCM unless specified in testing procedure. DO NOT pierce wiring. If backprobing is specified, always backprobe harness side of connector. DO NOT probe connector side.

4) Isolate both ends of circuit and turn ignition off whenever checking for shorts or continuity, unless specified otherwise. Disconnect solenoids and switches before checking circuit continuity or energizing solenoids.

Solenoid Performance Check

To properly diagnose solenoid, check it in ON and OFF positions. When test procedure requires click test, check appropriate solenoid as follows.

1. BANK/INJ Install breakout box. Connect PCM to breakout box. Turn ignition on. Injectors should click when engine is cranked.
2. CANP Install breakout box, leaving PCM disconnected. Turn ignition on. Apply vacuum to vacuum nipple of canister purge solenoid. Using jumper wire, ground CANP test pin at breakout box. Vacuum should release.
3. EGRC Install breakout box, leaving PCM disconnected. Turn ignition Apply vacuum to EGR valve. Vacuum should hold. Using jumper wire, ground ERGC test pin of breakout box. Vacuum should release.
4. EGRV Install breakout box, leaving PCM disconnected. Turn ignition Apply vacuum to EGR valve. Vacuum should not hold. Using jumper wire, ground EGRV test pin of breakout box. Apply vacuum to EGR valve. Vacuum should hold.
5. EVR Disconnect vacuum hoses at solenoid. Verify airflow between ports on solenoid. See VACUUM SPECIFICATION (EVR SOLENOID) table. Install breakout box, leaving PCM disconnected. Turn ignition on. Using jumper wire, ground EVR test pin of breakout box. Verify airflow between ports on solenoid. VACUUM SPECIFICATIONS Between Ports Airflow With Ignition Off "A" & "B" No "A" & "C" No "B" & "C" Yes With Ignition On (1) "A" & "B" Yes "A" & "C" No "B" & "C" No (1) With the EVR test pin grounded at the breakout box.
6. FPRC Install breakout box, leaving PCM disconnected. Turn ignition Apply vacuum to FPRC solenoid. Vacuum should hold. Using jumper wire, ground FPRC test pin of breakout box. Vacuum should release.
7. HSIA Install breakout box, leaving PCM disconnected. Turn ignition Apply vacuum to HSIA solenoid. Vacuum should hold. Using jumper wire, ground HSIA test pin of breakout box. Vacuum should release.
8. IAC Install breakout box, leaving PCM disconnected. Turn ignition Using jumper wire, ground IAC test pin of breakout box intermittently. IAC solenoid should click when test pin is grounded.
9. VRIS Disconnect vacuum hoses at solenoid. Verify airflow between ports on solenoid. See VACUUM SPECIFICATION (VRIS SOLENOID) table. Install breakout box, leaving PCM disconnected. Turn ignition on. Using jumper wire, ground VRIS test pin of breakout box. Verify airflow between ports on solenoid.

VACUUM SPECIFICATIONS

Simulated PCM Solenoid Activation

To further diagnose solenoid, ensure PCM and related circuits are capable of operating solenoid. When test procedure requires simulated PCM solenoid activation, check function of appropriate solenoid. Solenoid should function as follows.

1. BANK/INJ Solenoid should activate during cranking and while engine is running.
2. CANP With engine temperature more than 140°F (60°C), solenoid should activate during vehicle cruise or acceleration.
3. EGRC With engine temperature more than 140°F (60°C), solenoid should activate at normal driving (cruising).
4. EGRV With engine temperature more than 140°F (60°C), solenoid should activate during idle, deceleration or at wide open throttle.
5. EVR With engine temperature more than 158°F (70°C), solenoid should activate when engine speed is less than 1500 RPM.
6. FPRC On 1.8L, coolant temperature more than 158°F (70°C). Solenoid should activate with engine speed less than 1500 RPM and remain activated for 2 minutes after engine is started.
7. HSIA Solenoid should activate when engine speed is less than 5000 RPM.
8. IAC Solenoid should activate during engine cranking and running.
9. VRIS Solenoid should activate with engine at low speed.

Switch Performance Check

Switch must be checked in ON (closed) and OFF (open) positions. Switch should function as follows

1. ACS Switch is closed when A/C is on and blower is operating.
2. BLMT On 1.8L, switch is closed with fan selector switch is in 2nd, 3rd or 4th position.
3. CCPS Switch is closed with A/C on and system pressure within normal operation range.
4. HPS Switch is closed with A/C on and system pressure exceeding normal operating range.
5. IDL Switch is open when throttle is depressed.
6. CPP/PNP CPP switch is closed when clutch pedal is depressed. PNP switch is closed when transaxle is in Neutral.
7. PSP Switch is open when system pressure is less than 245 psi (16.9 kg/cm 2 ). Switch is closed when system pressure is greater than 290 psi (20.0 kg/cm 2 ).
8. WOT Switch is closed when throttle is open.

Check switch in ON and OFF positions. Install breakout box, leaving PCM disconnected. Turn ignition on. Measure voltage between breakout box test pin of switch being tested and ground. Switch should function as follows

1. BOO Depress clutch pedal to close switch. Battery voltage should be present.
2. DEF Turn rear defroster on to close switch. Battery voltage should be present.
3. HDLT Turn headlight on to close switch. Battery voltage should be present.
4. VST Switch is closed when engine is cranking. About 9 volts should be present.

TP Sensor Circuit & Connector Terminals (1.8L A/T) ID. Scheme 173

Note. Enter this test only when a Code 12 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test. To prevent replacement of good components, check following non-EEC components for fault: idle speed or throttle stop adjustments, throttle shaft or linkage, and cruise control linkage.

CIRCUIT PIN IDENTIFICATION

1) Check System Integrity Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, go to next step.

2) Check TP Sensor Voltage Turn ignition off. Install breakout box. Install PCM to breakout box. Turn ignition on. Measure voltage at TP test pin at breakout box. Slowly depress accelerator pedal, and compare voltage to specifications shown in VOLTAGE & RESISTANCE SPECIFICATIONS (TP SENSOR) table. If voltage is as specified, and no other problem or code is found, replace PCM. If voltage is not as specified, go to next step.

3) Check VREF Turn ignition off. Disconnect TP sensor connector. Turn ignition on. Measure voltage at VREF terminal of TP sensor connector. On 1.8L A/T, if voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, go to TEST VREF.

4) Check Wires To PCM (1.8L A/T) Turn ignition off. With breakout box installed, disconnect PCM connectors. Disconnect TP sensor connector. Measure and record resistances of TP wire and SIG RTN wire between test pins at breakout box and TP sensor connector. Measure and record resistance between ground and TP test pin at breakout box. If resistances are less than 5 ohms between test pins and TP sensor connector, and more than 10,000 ohms between ground and TP test pin, replace TP sensor. If resistance is not as specified, repair TP wire between TP sensor connector and PCM.

VOLTAGE & RESISTANCE SPECIFICATIONS

VAF Sensor Circuit & Connector Terminals ID (1.8L). Scheme 174

Note. Enter this test only when a Code 08 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test. To avoid unnecessary use of diagnostic time, check for unmetered air leaks between VAF sensor and throttle body. This test is intended to diagnose VAF and VMREF circuits only.

CIRCUIT PIN IDENTIFICATION

1) Check System Integrity Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, go to next step.

2) Check VAF Voltage Turn ignition off. Install breakout box. Connect PCM to breakout box. Access VAF measuring vane (air door). Turn ignition on. Measure voltage between VAF and SIG RTN test pins at breakout box while moving air door. If voltage is not as specified, go to next step. See VOLTAGE SPECIFICATIONS (VAF SENSOR) table. If voltage is as specified and no other problem or code is found, replace PCM.

3) Check VAF Signal From VAF Meter Turn ignition off. Access VAF measuring vane. Disconnect VAF meter connector. Connect a jumper wire between VREF and SIG RTN terminals at VAF meter connector. Turn ignition on. Measure voltage between VAF terminal at VAF meter and SIG RTN terminal at VAF meter connector while moving air door. Compare voltage to specifications shown in VOLTAGE SPECIFICATIONS (VAF SENSOR) table. If voltage is as specified, and no other problem or code is found, replace PCM. If voltage is not as specified, go to next step.

4) Check VREF At VAF Meter Turn ignition off. Disconnect VAF meter connector. Turn ignition on. Measure voltage between VREF and SIG RTN terminals at VAF meter connector. If voltage is 4.5-5.5 volts, replace VAF meter. If voltage is not 4.5-5.5 volts, go to TEST VREF.

VOLTAGE SPECIFICATIONS

Identifying Power Relay Circuit. Scheme 175

Identifying Power Relay Connector Terminals (1.8L). Scheme 176

Note. Enter this test only when directed here by other circuit tests. To prevent replacement of good components, check for faults in following non-EEC components: ignition switch, alternator, battery cables, ground straps and voltage regulator. This test is only intended to diagnose following circuits: VPWR and GND.

CIRCUIT PIN IDENTIFICATION

1) Check Circuit Integrity Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, check battery voltage and charge condition. Service as necessary, and go to next step.

2) Check VPWR To PCM Turn ignition off. Install breakout box, leaving PCM disconnected. Turn ignition on. Measure voltage at VPWR test pin at breakout box. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, go to step 4).

3) Check PCM Grounds Turn ignition off. With breakout box installed and PCM disconnected, measure resistance between ground and each GND test pin at breakout box. If all resistances are less than 5 ohms, VPWR circuit is okay. Return to circuit test that sent you here. If one or more resistances is 5 ohms or more, repair open in GND wire(s).

4) Check VPWR Wire From Power Relay To PCM Ensure ignition is off, breakout box is installed and PCM is disconnected. Remove power relay. Relay is located inside engine compartment fuse/relay box. Measure resistance between VPWR test pin at breakout box and VPWR at power relay connector. If voltage is less than 5 ohms, go to next step. If voltage is 5 ohms or more, repair open VPWR wire.

5) Check Ground At Power Relay Turn ignition off. Remove power relay. Measure resistance between ground and GND terminal at power relay connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open power relay ground wire.

6) Check Voltage At Power Relay Turn ignition off. Measure voltage at BATT terminal at power relay connector. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, check fuse to power relay. Fuse is located in engine compartment fuse/relay box. Replace fuse if blown. If fuse is okay, repair wire between fuse and power relay.

7) Check Power To Power Relay Turn ignition on. Measure voltage at PWR terminal at power relay connector. If voltage is more than 10 volts, replace power relay. If voltage is 10 volts or less, check 15-amp fuse to BATT wire. Fuse is located in instrument panel fuse block. Replace fuse if blown. If fuse is okay, repair PWR wire.

Identifying VREF Connector Terminals (1.8L A/T). Scheme 177

Identifying VREF Connector Terminals (1.8L M/T). Scheme 178

Note. Perform this test when a check for VREF has failed in a sensor input circuit test. This test is only intended to diagnose following circuits: VREF and SIG RTN.

CIRCUIT PIN IDENTIFICATION

1) Check System Integrity Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If fault is found, repair as necessary. If no fault is found, go to next step.

2) Check VREF At PCM Turn ignition off. Install breakout box. Connect PCM to breakout box. Turn ignition on. Measure voltage between VREF and SIG RTN test pins at breakout box. If voltage is 4.5-5.5 volts, go to next step. If voltage is not 4.5-5.5 volts, go to TEST VPWR. If VPWR circuit is okay, replace PCM.

3) Check For VREF At Sensor Turn ignition off. Disconnect BARO, EVP, VAF, MC-VAF and TP sensor connectors (if equipped). Turn ignition on. Measure voltage at VREF wire at each disconnected sensor connector. If all readings are 4.5-5.5 volts, VREF circuit is okay. Return to circuit test that sent you here. If any reading is 10-12 volts, repair short to power in VREF wire(s). If any reading is zero volts, go to next step.

4) Check For Open VREF Wires Turn ignition off. With breakout box installed, disconnect PCM connectors. Measure resistance between VREF test pin at breakout box and VREF terminal of sensor connectors. If all resistance readings are less than 5 ohms, go to next step. If any reading is 5 ohms or more, repair open in VREF wire(s).

5) Check For Short In VREF Wires Ensure ignition is off. Measure resistance between ground and VREF test pin at breakout box. If all resistance readings are more than 10,000 ohms, repair SIG RTN wire to PCM. If any resistance reading is 10,000 ohms or less, repair short in wire in question.