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

QUICK TEST

Note. Accuracy of self-test data depends on correct operation of non-EEC components and systems. Correct all non-EEC problems in engine, ignition or fuel system attempting to diagnose EEC system.

CODE-TO-TEST MENU

Note. In order to allow for a more detailed and complete title to be displayed in the menu screen, specific Circuit Tests are titled "TEST". For example, TEST MIL is referred to as TEST MIL.

CODE REFERENCE CHART (1.8L)

SWITCH MONITOR TEST

Perform this test if no code is present after performing KOEO and KOER self-tests. Switch monitor tests determine if electrical signals to PCM from input devices are correct. In this procedure, each device is tested individually. Perform test using Super Star II tester or Analog Volt-Ohmmeter (VOM).

TEST EQUIPMENT

Following equipment is recommended for diagnosing and testing EEC system. DO NOT attempt to test this system without proper equipment. Damage to vehicle components may result if improper equipment is used.

1. Self-Test Automatic Read-Out (Super Star II) diagnostic tester is recommended but not required. It is specially built for EEC systems and is used to display 2-digit (numeric) codes programmed into powertrain control module. Aftermarket scan tools are also available.
2. Analog Volt-Ohmmeter (VOM) with 0-20V DC range can be used, as an alternative to diagnostic tester, to read codes.
3. Digital Volt-Ohmmeter (DVOM) with minimum 10-megohm input impedance.
4. A breakout box is required to perform certain tests on system. Test pin number mentioned in circuit tests refers to test pin number on breakout box. Breakout box Adapter (T92C-6000-AH) has an A/B position selector switch. Ensure switch is in correct position for each test step. If no switch position is given, switch can be in either position. Once breakout box has been installed during a test sequence, it may stay connected for remainder of that test, unless stated otherwise. Aftermarket breakout boxes are also available.
5. Vacuum gauge with 0-30 in. Hg range and resolution (units on scale) of 1 in. Hg.
6. Tachometer with 0-6000 RPM range, +/- 40 RPM accuracy, and a resolution of 20 RPM.
7. Vacuum pump with 0-30 in. Hg range.
8. Timing light.
9. Spark Tester (D81P-6666-A or ST-125) is required. A modified side electrode spark plug is not sufficient for these procedures.
10. Fuel Injection Pressure Gauge (T80L-9974-A).
11. 12-volt test light (non-powered type).
12. Jumper wire about 15" long.

Note. Following circuit tests and illustrations are provided courtesy of Ford Motor Co. Complete EEC system wiring diagrams may be found in WIRING DIAGRAMS .

Note. In order to allow for a more detailed and complete title to be displayed in the menu screen, specific Circuit Tests are titled "TEST". For example, TEST MIL is referred to as TEST MIL.

CODE REFERENCE CHART (1.8L)

Note. Following circuit tests and illustrations are provided courtesy of Ford Motor Co. Complete EEC system wiring diagrams may be found in WIRING DIAGRAMS .

TEST BARO - BAROMETRIC PRESSURE SENSOR

Note. Enter this test only when Code 14 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test. To prevent unnecessary replacement of components, check for fault in following non-EEC items: atmospheric barometer reading (unusually high or low), vacuum lines (blocked) and basic mechanical engine components. This test is intended to diagnose BARO circuit only.

Note. Barometric pressure sensor is built into PCM and cannot be replaced separately. If Code 14 appears repeatedly after clearing codes, replace PCM.

Visually check all wiring, connectors and components for evidence of damage, shorting or looseness. If a fault is found, repair as necessary. If no fault is found, erase codes from memory. Perform KOEO and KOER self-tests. See QUICK TEST. If Code 14 continues to appear, replace PCM.

Distributor Connector Terminals (1.8L) ID. Scheme 146

Note. Enter this test only when Code 03 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test. This test is intended to diagnose CID circuit only.

Note. CID is incorporated with Crankshaft Position (CKP) sensor inside distributor.

CIRCUIT PIN IDENTIFICATION

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

2) Check CID Signal Turn ignition off. Install breakout box. Connect PCM to breakout box. Measure voltage at CID test pin at breakout box while bumping starter. If voltage fluctuates between zero and 5 volts, circuit is okay. If no other problem or code is found, replace PCM. If voltage does not fluctuate between zero and 5 volts, go to next step.

3) Check VPWR To Distributor Ensure ignition is off. Disconnect distributor connector. Turn ignition on. Measure voltage at VPWR wire at distributor connector. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, go to TEST VPWR. If VPWR circuit is okay, repair VPWR wire to distributor.

4) Check Distributor Ground Turn ignition off. Ensure distributor is disconnected. Measure resistance of GND wire between distributor connector and ground. If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open GND wire.

5) Check For Open CID Wire Ensure ignition is off. With breakout box installed, disconnect PCM connectors. Measure resistance of CID wire between ground and CID test pin at breakout box. If resistance is more than 10,000 ohms, replace distributor. If resistance is 10,000 ohms or less, repair short to ground in CID wire.

6) Check For Short In CID Wire With breakout box installed and PCM connectors disconnected, measure resistance of CID wire between ground and CID test pin at breakout box. If resistance is more than 10,000 ohms, replace distributor. If resistance is 10,000 ohms or less, repair short to ground in CID wire.

TEST CKP (1.8L) - CRANKSHAFT POSITION SENSOR

Note. Enter this test only when Code 02 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test. This test is intended to diagnose CKP circuit only.

CIRCUIT PIN IDENTIFICATION

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

2) Check VPWR To Distributor Turn ignition off. Disconnect distributor connector. Turn ignition on. Measure voltage between ground and distributor VPWR wire. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, perform TEST VPWR. If results of TEST VPWR are okay, repair open in VPWR wire to distributor.

3) Check Distributor Ground Ensure ignition is off and distributor is disconnected. Measure resistance between distributor GND wire and ground. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in distributor GND wire.

4) Check Distributor To PCM Wires Ensure ignition is off and distributor is disconnected. Install breakout box, leaving PCM disconnected. Measure and record resistance between CKP test pin at breakout box and CKP terminal at distributor connector. Measure and record resistance between ground and CKP test pin at breakout box. If resistance is less than 5 ohms between CKP test pin and CKP terminal at distributor connector and more than 10,000 ohms between ground and CKP test pin, replace CKP sensor. If resistance is not as specified, repair CKP wire between distributor connector and PCM.

Identifying ECT Connector Terminals (1.8L). Scheme 147

Note. Enter this test only when a Code 09 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test. To prevent unnecessary diagnosis, inspect coolant level, oil level, cooling fan, thermostat and airflow to radiator for obstruction before electronic testing. This test is intended to diagnose ECT circuit only.

CIRCUIT PIN IDENTIFICATION (ECT)

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

2) Check ECT Sensor Resistance Run engine until engine coolant reaches temperatures specified. See RESISTANCE SPECIFICATIONS (ECT SENSOR) table. Monitor temperature at ECT sensor using Rotunda Digital Thermometer (055-00100). Turn ignition off. Install breakout box, leaving PCM disconnected. Measure resistance between ECT and SIG RTN test terminals at breakout box. Compare readings with RESISTANCE SPECIFICATIONS (ECT SENSOR) table. If resistance is not as specified, go to next step. If resistance is as specified, ECT circuit is okay. If no other problem or code is found, replace PCM.

RESISTANCE SPECIFICATIONS

3) Check ECT Circuit Turn ignition off. With breakout box installed and PCM disconnected, disconnect ECT sensor connector. Measure and record resistance between ECT test pin at breakout box and ECT terminal at ECT sensor connector. Measure and record resistance between ground and ECT test pin at breakout box. If resistance between ECT test pin at breakout box and ECT terminal at ECT sensor connector is less than 5 ohms and resistance between ground and ECT test pin at breakout box is 10,000 ohms, go to next step. If resistance is not as specified, repair ECT wire between ECT sensor connector and PCM.

4) Check SIG RTN Circuit (1.8L) Ensure ignition is off and ECT sensor is disconnected. With breakout box installed and PCM disconnected, measure resistance between SIG RTN test pin at breakout box and SIG RTN terminal at ECT sensor connector. If resistance is less than 5 ohms, replace ECT sensor. If resistance is 5 ohms or more, repair SIG RTN wire between ECT sensor connector and PCM.

IAT Sensor Connector Terminals (1.8L) ID. Scheme 148

Note. Enter this test only when a Code 10 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test. This test is intended to diagnose the IAT circuit only.

CIRCUIT PIN IDENTIFICATION

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

2) Check IAT Resistance Turn ignition off. Install breakout box, leaving PCM disconnected. Access IAT sensor. IAT sensor is located in the Volume Airflow (VAF) meter. Monitor temperature at IAT sensor using Rotunda Digital Thermometer (055-00100). Measure resistance between IAT and SIG RTN test pins at breakout box. Compare readings with RESISTANCE SPECIFICATIONS (IAT SENSOR) table. If resistance is not as specified, go to next step. If resistance is as specified, IAT circuit is okay. If no other problem or code is found, replace PCM.

RESISTANCE SPECIFICATIONS

3) Check For Open IAT Wire Ensure ignition is off, breakout box is installed and PCM is disconnected. On 1.8L, disconnect VAF sensor connector. Measure resistance between IAT test pin at breakout box and IAT terminal at VAF, MC-VAF or IAT sensor connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open the IAT wire.

4) Check For Short In IAT Wire Ensure ignition is off, breakout box is installed and PCM is disconnected. Measure resistance between ground and IAT test pin at breakout box. If resistance is more than 10,000 ohms, go to step 6).

Note. A break in step numbering sequence occurs at this point. Procedure skips from step 4) to step 6). No test procedures have been omitted.

6) Check IAT Sensor SIG RTN (1.8L) Ensure ignition is off. Measure resistance between SIG RTN test pin at breakout box and SIG RTN terminal at VAF sensor connector or IAT sensor connector. If resistance is 5 ohms or more, repair IAT sensor SIG RTN wire. If resistance is less than 5 ohms, replace VAF sensor on 1.8L.

IDM Circuit (1.8L) ID. Scheme 149

ICM Connector Terminals (1.8L) ID. Scheme 150

Ignition Coil Connector Terminals (1.8L) ID. Scheme 151

Note. Enter this test only when Code 01 is displayed during self-test procedures (KOEO or KOER). This test is only intended to diagnose following EEC system-related spark and electrical circuits (IDM, SPOUT and VPWR to ignition).

CIRCUIT PIN IDENTIFICATION

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

2) Check Coil Spark Connect spark tester between coil secondary cable and ground. Crank engine. If spark is present and no other fault except for Code 01 is found, replace PCM. If spark is not present, go to next step.

3) Continuous IDM At Coil Turn ignition off. Disconnect ignition coil connector. Connect test light between IDM and PWR wires at ignition coil. Crank engine. If test light flashes, go to next step. If test light does not flash, go to step 5).

4) Check Power To Ignition Coil Disconnect ignition coil connector. Turn ignition on. Measure voltage between ground and PWR wire at ignition coil. If voltage is greater than 10 volts, replace coil. If reading is 10 volts or less, repair PWR circuit between ignition coil and ignition switch.

5) Check For Continuous IDM From Ign Control Module (ICM) Disconnect ICM connector. Connect a jumper wire between SPOUT and GND terminals at ICM connector. Connect test light between IDM terminal at ICM connector and PWR wire at ignition coil. Crank engine. If test light does not flash, go to next step. If test light flashes as engine is cranked, repair IDM wire between ICM and coil.

6) Check ICM Ground Remove ICM connector. Connect test light between PWR wire at ignition coil and GND wire at ICM connector. Turn ignition on. If light does not come on, repair ICM GND wire. If light comes on, go to next step.

7) Check SPOUT Circuit From ICM Turn ignition off. Disconnect ICM connector. Install breakout box, leaving PCM disconnected. Measure resistance between SPOUT test pin at breakout box and SPOUT terminal at ICM connector. If resistance is less than 5 ohms, check SPOUT wire for shorts to any other circuit. If wiring is okay, replace PCM. If resistance is 5 ohms or more, repair SPOUT wire between ICM connector and PCM.

Instrument Cluster Connector Terminals (1.8L) ID. Scheme 152

Note. Enter this test only when instructed by QUICK TEST. This test is intended to diagnose MIL circuit only.

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 MIL Operation Turn ignition off. Install breakout box, leaving PCM disconnected. Turn ignition on. Ground MIL test pin (No. 51) at breakout box. If MIL is on, MIL circuit is okay. If codes do not flash on MIL during QUICK TEST or MIL never comes on, replace PCM. If MIL is off, go to next step.

3) Check MIL Bulb Turn ignition off. Remove instrument cluster. Remove and inspect MIL bulb. Replace bulb as necessary. If bulb is okay, go to next step.

4) Check For Open MIL Wire Turn ignition off. Disconnect instrument cluster connector. Ensure ignition is off, breakout box is installed and PCM is disconnected. Measure resistance between MIL test pin (No. 31) at breakout box and MIL terminal at instrument cluster connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in MIL wire.

5) Check For Short In MIL Wire Ensure ignition is off, breakout box is installed and PCM and instrument cluster connectors are disconnected. Measure resistance between ground and MIL test pin (No. 51) at breakout box. If resistance is more than 10,000 ohms, replace instrument cluster printed circuit board. If resistance is 10,000 ohms or less, repair short to ground in MIL wire.

TEST O2S (1.8L) - OXYGEN SENSOR

Note. Enter this test only when Code 15 (lean) or Code 17 (rich) is displayed during self-test procedures (KOEO or KOER). This test is intended to diagnose O2S circuit.

Note. Voltage that remains more than .55 volt indicates a continuously rich condition. Voltage that remains less than .55 volt indicates a continuously lean condition. Rich or lean conditions may also be an indication of another problem.

1) Check O2S Voltage Ensure engine is at normal operating temperature. Turn ignition off. Disconnect O2S connector. Measure voltage at O2S connector. Voltage should increase as engine speed increases and decrease as engine speed decreases; voltage should be 0.2-0.8 volt at idle. If voltage is as specified, go to next step. If voltage is not as specified, replace O2S.

2) Check O2S Circuit Turn ignition off. Install breakout box, leaving PCM disconnected. Measure resistance between O2S test pin at breakout box and O2S connector. If resistance is less than 5 ohms, O2S circuit is okay. If no other problem or code is found, replace PCM.

TEST PGC - POWER & GROUND CHECK

Note. Enter this test only when directed here by TEST STO or by another test. This test is intended to diagnose Keep Alive Power (KAPWR) and Ground (GND) circuits.

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 Voltage Turn ignition off. Install breakout box, leaving PCM disconnected. Measure voltage at KAPWR test pin at breakout box. If reading is about battery voltage, go to next step. If reading is less than battery voltage, repair wire as necessary.

3) Check Grounds Ensure ignition is off, breakout box is installed and PCM is disconnected. Measure resistance between ground and GND test pin at breakout box. Repeat test for each ground wire. If resistance is less than 5 ohms, replace PCM. If resistance is 5 ohms or more, repair open ground wire.

Relay Connector Terminals - WAC Relay (1.8L) ID. Scheme 153

Note. Enter this test only when a Code 67 or Code 68 is displayed during self-test procedures (KOEO or KOER) or when directed here from another circuit test or SWITCH MONITOR TEST. This test is intended to diagnose following relays and circuits: A/C Relay (ACR), Fuel Pump Relay (FPR), High Condenser Fan Relay (HCFAN), High Cooling Fan Relay (HFAN), Low Condenser Fan Relay (LCFAN), Low Cooling Fan Relay (LFAN) and Wide Open Throttle A/C Cutoff Relay (WAC).

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) Perform Relay Click Test Turn ignition off. Install breakout box. Connect PCM to breakout box. Locate relay to be tested. Turn ignition on. Feel and/or listen to relay while grounding appropriate relay test pin at breakout box. If relay clicks, relay is okay. If relay does not click, go to next step.

3) Check For Open Relay Wire To PCM Turn ignition off. With breakout box installed, disconnect PCM connectors. Disconnect relay to be tested. Measure resistance between breakout box test pin of relay being tested and relay terminal to PCM at relay connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open wire between PCM and relay connector.

Note. When testing HFAN or HCFAN relays, both HFAN and HCFAN relays must be disconnected.

4) Check For Short In Relay Wire To PCM Turn ignition off. With PCM disconnected and breakout box installed, disconnect relay to be tested. Measure resistance between ground and breakout box test pin of relay being tested. If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 or less, repair short to ground in wire between PCM and relay connector.

5) Check Power To Suspect Relay Turn ignition off. Disconnect relay to be tested. Turn ignition off. Measure voltage at PWR terminal at relay connector. If voltage is more than 10 volts, replace relay. If voltage is 10 volts or less, repair PWR wire.

Identifying Injector Connector Terminals (1.8L). Scheme 154

Identifying Typical Solenoid Connector Terminals. Scheme 155

Identifying EVR/VRIS Solenoid Ports. Scheme 156

Note. Enter this test only when Code 25, 26, 28, 29, 34, 41 or 46 is displayed during self-test procedures (KOEO or KOER). This test is intended to diagnose following solenoids and circuits: Canister Purge (CANP), EGR Control (EGRC), EGR Vent (EGRV), EGR Vacuum Regulator (EVR), Fuel Pressure Regulator Control (FPRC), High Speed Inlet Air Control (HSIA), Idle Air Control (IAC), injectors (INJ) or injector banks (BANK), and Variable Resonance Induction System Solenoids (VRIS).

CIRCUIT PIN IDENTIFICATION

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

2) Solenoid Function Turn ignition off. Install breakout box, leaving PCM disconnected. Check function of appropriate solenoid. See SOLENOID PERFORMANCE CHECK. If solenoid functions okay, test is complete. If no other problem or code is found, replace PCM. If solenoid does not function properly, go to next step.

3) Check Power To SolenoID Turn ignition off. Disconnect connector of solenoid to be tested. Turn ignition on. Measure voltage between connector ground and VPWR terminal at solenoid connector. If voltage is less than battery voltage, go to TEST VPWR. If VPWR circuit is okay, repair VPWR wire to solenoid. If voltage is battery voltage, go to next step.

4) Check For Open Solenoid Wire To PCM Turn ignition off. Ensure breakout box is installed and PCM is disconnected. Disconnect connector of solenoid to be tested. Measure resistance between solenoid test pin at breakout box and terminal at solenoid connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open solenoid wire to PCM.

5) Check For Short In Solenoid Wire To PCM Turn ignition off. Ensure breakout box is installed and PCM is disconnected. Disconnect connector of solenoid to be tested. Measure resistance between ground and solenoid test pin at breakout box. If resistance is more than 10,000 ohms, replace solenoid. If resistance is 10,000 ohms or less, repair short to ground in solenoid wire.

TEST SML - SWITCH MONITOR LIGHT

Note. Enter this test only when directed here by SWITCH MONITOR TEST. Switch monitor light is located on Super Star II/Super Mecs adapter. This test is intended to diagnose SML circuit only.

1) Check For Open SML Wire Turn ignition off. Install breakout box, leaving PCM disconnected. Measure resistance between SML test pin (No. 38) at breakout box and SML terminal at data link connector. see scheme 16 If resistance is less than 5 ohms, go to next step. If resistance is at least 5 ohms, repair open SML wire.

2) Check For Short In SML Wire Turn ignition off. With breakout box installed and PCM disconnected, measure resistance between ground and SML test pin (No. 38) at breakout box. If resistance is more than 10,000 ohms, replace PCM. If resistance is 10,000 ohms or less, repair short in SML wire.

Type "A" Switch ID. Scheme 157

A/C Switch Ckt & Connector ID (Type "A"). Scheme 158

Idle Switch Circuit & Connector ID (Type "A"). Scheme 159

Type "B" Switch Circuit ID. Scheme 160

Idle & WOT Switch Ckts & Connector ID (M/T, Type "B"). Scheme 161

Type "C" Switch Circuit ID. Scheme 162

PNP/CPP Switch Ckts & Connector ID (M/T Type "C"). Scheme 163

Note. Enter this test only when directed here by SWITCH MONITOR TEST. This test is intended to diagnose following switches and circuits: A/C Switch (ACS), Blower Motor Switch (BLMT), Clutch Cycling Pressure Switch (CCPS), Clutch Pedal Position Switch (CPP), High Pressure Switch (HPS), Idle Switch (IDL), Park/Neutral Position Switch (PNP), Power Steering Pressure Switch (PSP), Rear Defroster Switch (DEF) and Wide Open Throttle Switch (WOT).

CIRCUIT PIN IDENTIFICATION

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

Note. The idle switch is adjustable. If 12 volts is present with switch closed, adjust switch. See THROTTLE POSITION (TP) SENSOR in the ADJUSTMENTS article in this section After adjustment procedure is completed, repeat step 2).

2) Check Switch Signal To PCM Install breakout box. Connect PCM to breakout box. Measure voltage between ground and breakout box test pin of switch being tested. Check voltage with switch in open and closed positions. See SWITCH PERFORMANCE CHECK. Voltage should switch from less than one volt (switch closed) to more than 10 volts (switch open). 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 For Open Switch Wire Ensure ignition is off. With breakout box installed, disconnect PCM connectors. Disconnect switch to be tested. Measure resistance between breakout box test pin of switch being tested and corresponding terminal at switch connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in wire tested.

4) Check For Short In Switch Wire Ensure ignition is off, breakout box is installed and PCM is disconnected. Measure resistance between ground and breakout box test pin of switch being tested. If resistance is less than 5 ohms, repair short to ground in wire between switch and PCM. If testing PSP or IDL switch, if resistance is 5 ohms or more, replace switch. On all other switches, if resistance is 5 ohms or more, go to next step.

5) Check Ground At Suspect Switch Turn ignition off. Measure resistance between ground and GND terminal at connector of switch being tested. If resistance is less than 5 ohms, replace switch. If resistance is at least 5 ohms, repair open in ground wire.

TEST STI - SELF-TEST INPUT

Note. Enter this test only when Super Star II tester displays STO LO or VOM displays zero volt.

CIRCUIT PIN IDENTIFICATION

1) Check System Integrity Visually check all wiring and connectors 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 For Open STI Wire Turn ignition off. Install breakout box, leaving PCM disconnected. Measure resistance between STI test pin at breakout box and PCM STI terminal at Data Link Connector (DLC). see scheme 24 If resistance is less than 5 ohms, go to next step. If resistance is at least 5 ohms, repair open PCM STI wire between PCM and DLC.

3) Check For Short In PCM STI Wire Ensure ignition is off, breakout box is installed and PCM disconnected. Measure resistance between ground and STI test pin at breakout box. If resistance is more than 10,000 ohms, go to TEST STO. If resistance is 10,000 ohms or less, repair short to ground in PCM STI wire.

TEST STO - SELF-TEST OUTPUT

Note. Enter this test only when instructed by TEST STI.

CIRCUIT PIN IDENTIFICATION

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

2) Check For Open STO Wire Turn ignition off. Install breakout box, leaving PCM disconnected. Measure resistance between STO test pin at breakout box and PCM STO terminal at Data Link Connector (DLC). see scheme 24 If resistance is less than 5 ohms, go to next step. If resistance is at least 5 ohms, repair open PCM STO wire.

3) Check For Short In STO Wire Ensure ignition is off, breakout box is installed and PCM disconnected. Measure resistance between ground and STO test pin at breakout box. If resistance is more than 10,000 ohms, go to TEST PGC. If resistance is 10,000 ohms or less, repair short to ground in PCM STO wire.

Defroster Switch Ckt & Connector ID (1.8L 3 & 5-Door). Scheme 164

Defroster Switch Ckt & Connector ID (1.8L 4-Door). Scheme 165

Note. Enter this test only when directed here from SWITCH MONITOR TEST. This test is intended to diagnose following switches and circuits: Brake On-Off (BOO) switch, Headlight (HDLT) switch, Rear Window Defrost (DEF) and Vehicle Start (VST) switch.

CIRCUIT PIN IDENTIFICATION

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

2) Check Switch Signal To PCM Turn ignition off. Install breakout box, leaving PCM disconnected. Turn ignition on. Measure voltage between breakout box test pin of switch being tested and ground. Check voltage with switch in ON (closed) and OFF (open) positions. See SWITCH PERFORMANCE CHECK. If voltage is as specified and no other problem or code is found, replace PCM. On headlight switch, if voltage is not as specified but headlights work, check for open wire. If headlights do not work, test headlight switch. See STEERING COLUMN SWITCHES article in the ACCESSORIES/SAFETY EQUIPMENT Section. On all other switches, if voltage is not as specified, go to next step.

3) Check Power To Switch Turn ignition off. Disconnect connector of switch to be tested. Turn ignition on. Measure voltage at PWR terminal of switch. If voltage is about battery voltage, go to next step. If voltage is less than battery voltage, repair open PWR wire.

4) Check Switch Continuity Turn ignition off. Disconnect connector of switch to be tested. Measure resistance between switch terminals. Resistance should be less than 5 ohms with switch closed and more than 10,000 ohms with switch open. If resistance is not as specified, replace switch. If resistance is as specified and no other problem or code is found, replace PCM.

TEST VSS (1.8L) - VEHICLE SPEED SENSOR

Note. Enter this test only when directed here by other circuit tests.

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 VSS Signal Turn ignition off. Disconnect VSS connector. Remove VSS from transaxle. Check continuity between VSS connector terminals while rotating speedometer drive gear. If continuity exists 8 times per one revolution of speedometer drive gear, sensor is okay. Check wires between VSS connector and PCM. Repair wires as necessary. If continuity does not exist 8 times per one revolution of speedometer drive gear, replace VSS.

EEC Wiring Diagram (1.8L A/T - 1 of 2). Scheme 166

EEC Wiring Diagram (1.8L A/T - 2 of 2). Scheme 167

EEC Wiring Diagram (1.8L M/T - 1 of 2). Scheme 168

EEC Wiring Diagram (1.8L M/T - 2 of 2). Scheme 169