Engine Control System & Engine Component Tests: Other Honda CR-V I рестайлинг

HEATED AIR INDUCTION SYSTEM (ODYSSEY)

Heated air induction system improves fuel economy in cold weather conditions and when engine is cold. When ambient air temperature is low, air temperature control valve opens air valve to allow heated air into engine.

1. Remove air cleaner. Check air valve operation. Blend door should not open to fresh air with wax element below 32°F (0°C). (Scheme 72) If blend door is not open to fresh air, go to next step. If blend door is open to fresh air, check blend door control shaft for binding or sticking. If blend door control shaft is okay, replace air cleaner housing.
2. Start engine and run at 3000 RPM with no loads and transmission in Park or Neutral until radiator fan comes on. Check air valve operation. Blend door should open to fresh air with wax element above 50°F (10°C). (Scheme 72) If blend door is open to fresh air, air valve is okay. If blend door is not open to fresh air, check blend door control shaft for binding or sticking. If blend door control shaft is okay, replace air cleaner housing.

Scheme 72

INTAKE AIR CONTROL SYSTEM (PRELUDE)

Intake control solenoid valve is located at right side of engine, under intake duct. See COMPONENT LOCATIONS . When engine speed is below 3970 RPM, PCM supplies ground to intake control solenoid. This opens intake control solenoid valve sending intake manifold vacuum to intake control diaphragm.

1. Start engine and allow to idle. Disconnect vacuum hose, located between intake control solenoid valve and intake control diaphragm, from upper port of intake control solenoid valve. See «VACUUM DIAGRAMS»(ref-3119) article. Check for vacuum at open port of intake control solenoid valve. If vacuum does not exist, go to next step. If vacuum exists, go to step 7 .
2. Reconnect vacuum hose to upper port of intake control solenoid valve. Disconnect vacuum hose from intake control vacuum tank. See «VACUUM DIAGRAMS»(ref-3119) article. Check for vacuum at open hose of intake control vacuum tank. If vacuum exists, go to next step. If vacuum does not exist, check for blockage or vacuum leak between intake control vacuum tank and intake manifold.
3. Turn ignition off. Disconnect intake control solenoid valve 2-pin connector. Turn ignition on. Measure voltage between intake control solenoid valve connector terminals. If battery voltage does not exist, go to next step. If battery voltage exists, replace intake control solenoid valve.
4. Measure voltage between ground and intake control solenoid valve harness connector terminal No. 2 (Black/Yellow wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Black/Yellow wire between intake control solenoid valve connector and No. 14 ECU (15-amp) fuse located in under-dash fuse/relay box. See «WIRING DIAGRAMS»(ref-3123) article.
5. Turn ignition off. Reconnect intake control solenoid valve 2-pin connector. Turn ignition on. Using backprobe set, connect a fused jumper wire between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and terminal No. 25 (White wire). Go to next step.
6. If intake control solenoid valve does not click when jumper wire is connected, repair open in White wire between intake control solenoid valve and PCM 32-pin connector "A". See «WIRING DIAGRAMS»(ref-3123) article. If intake control solenoid valve clicks when jumper wire is connected, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.
7. Increase engine speed to more than 4200 RPM. Check for vacuum at solenoid valve upper port. See «WIRING DIAGRAMS»(ref-3123) article. If vacuum does not exist, go to step 9 . If vacuum exists, disconnect intake control solenoid valve 2-pin connector. Check for vacuum again. If vacuum does not exist, go to next step. If vacuum exists, replace intake control solenoid valve.
8. Turn ignition off. Disconnect PCM 32-pin connector "A". See «PIN VOLTAGE CHARTS»(ref-3080) article. Check for continuity between ground and intake control solenoid valve 2-pin harness connector terminal No. 1 (White wire). If continuity exists, repair short in White wire between PCM 32-pin connector "A" and intake control solenoid valve. See «WIRING DIAGRAMS»(ref-3123) article. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.
9. Apply vacuum to vacuum hose disconnected from intake control solenoid valve upper port. See «VACUUM DIAGRAMS»(ref-3119) article. If vacuum holds, intake system is okay at this time. If vacuum does not hold, check vacuum hoses for proper connections or disconnected, cracked or leaking hoses. If vacuum hoses are okay, replace intake control diaphragm.

INTAKE AIR BY-PASS CONTROL SYSTEM (PRELUDE)

Intake Air By-Pass (IAB) control solenoid valve is located at lower rear of engine. See COMPONENT LOCATIONS . IAB control solenoid valve is off when engine speed is more than 4900 RPM.

1. Start engine and allow to idle. Disconnect vacuum hose from IAB control diaphragm. See «VACUUM DIAGRAMS»(ref-3119) article. Check for vacuum at hose. If vacuum does not exist, go to next step. If vacuum exists, go to step 7 .
2. Disconnect vacuum hose, located between IAB vacuum tank and intake manifold, from IAB vacuum tank. See «VACUUM DIAGRAMS»(ref-3119) article. Check for vacuum at hose of IAB vacuum tank. If vacuum exists, go to next step. If vacuum does not exist, repair blockage or vacuum leak between IAB vacuum tank and intake manifold.
3. Turn ignition switch off. Disconnect IAB control solenoid valve 2-pin connector. Measure voltage between IAB control solenoid valve harness connector terminals. If battery voltage does not exist, go to next step. If battery voltage exists, replace IAB control solenoid valve.
4. Measure voltage between ground and IAB control solenoid valve harness connector terminal No. 1 (Black/Yellow wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Black/Yellow wire between IAB control solenoid valve connector and No. 14 ECU (15-amp) fuse located in under-dash fuse/relay box. See «WIRING DIAGRAMS»(ref-3123) article.
5. Turn ignition off. Reconnect IAB control solenoid valve 2-pin connector. Turn ignition on. Using backprobe set, connect a fused jumper wire between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and terminal No. 26 (Red/Blue wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. Go to next step.
6. If IAB control solenoid valve does not click when jumper wire is connected, repair open in Red/Blue wire between IAB control solenoid valve and PCM 32-pin connector "A". See «WIRING DIAGRAMS»(ref-3123) article. If IAB control solenoid valve clicks when jumper wire is connected, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.
7. Increase engine speed to more than 5000 RPM. Check for vacuum at disconnected TAB control diaphragm hose. See «VACUUM DIAGRAMS»(ref-3119) article. If vacuum does not exist, IAB control system is okay. If vacuum exists, disconnect IAB control solenoid valve 2-pin connector. Check for vacuum again at disconnected IAB control diaphragm hose. If vacuum does not exist, go to next step. If vacuum exists, replace IAB control solenoid valve.
8. Turn ignition off. Disconnect PCM 32-pin connector "A". See «PIN VOLTAGE CHARTS»(ref-3080) article. Check for continuity between ground and IAB control solenoid valve harness connector terminal No. 2 (Red/Blue). If continuity exists, repair short in Red/Blue wire between PCM 32-pin connector "A" and IAB control solenoid valve. See «WIRING DIAGRAMS»(ref-3123) article. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.

INTAKE AIR BY-PASS CONTROL VALVE (PRELUDE)

Check valve shaft for binding and sticking, and ensure movement is smooth. Turn engine off. Ensure tab on IAB control valve contacts stop. (Scheme 73) Start engine and allow to idle. Ensure tab of IAB control valve contacts full-close screw. If control valve does not function properly, clean linkage and shafts using carburetor cleaner. If problem still exists after cleaning, disassemble intake manifold and inspect IAB valve assembly. See INTAKE MANIFOLD in appropriate article in ENGINES.

Scheme 73

Accord 3.0L & Odyssey

1. Start engine and allow to idle. Ensure engine coolant temperature is below 104°F (40°C). Disconnect vacuum hose located between air intake duct and Fuel Injection Air (FIA) control valve form air intake duct. Connect vacuum gauge to open end of hose. Raise and lower engine speed. Ensure vacuum gauge reading changes as RPM changes. If vacuum reading does not change, check for misrouted, leaking broken or clogged FIA system vacuum lines. If vacuum lines are okay, check for cracked or damaged FIA control valve. If vacuum reading does change, go to next step.
2. Run engine at 3000 RPM with no loads and transmission in Park or Neutral, until radiator fan comes on. Allow engine to idle. Ensure vacuum gauge reading does not change as RPM changes. If vacuum reading changes, check for misrouted, leaking broken or clogged FIA system vacuum lines. If vacuum lines are okay, check for cracked or damaged FIA control valve.

Accord (2.3L), Civic, CR-V, Odyssey & S2000

Note. Throttle stop screw is preset at factory and is not adjustable.

1. Check throttle cable for binding or sticking. If cable operation is okay, go to next step. If cable binds or sticks, check cable routing. Reroute or replace cable as necessary and go to next step.
2. Check throttle valve and shaft for being overly tight or loose. Replace throttle body as necessary. If throttle valve and shaft are okay, go to next step.
3. Check for clearance between throttle stop screw and throttle lever. If any clearance exists, replace throttle body. DO NOT adjust throttle stop screw.

Accord (3.0L) & Prelude

1. On Accord 3.0L, disconnect vacuum hose located between top of throttle body and top of Fuel Injection Air (FIA) control valve from FIA control valve. (Scheme 74) On Prelude, disconnect vacuum hose located between top or throttle body and EVAP purge control solenoid valve, from EVAP purge control solenoid valve. On all models, connect vacuum gauge to open end of hose. Start engine and run at 3000 RPM with no loads and transmission in Park or Neutral, until radiator fan comes on. Allow engine to idle. Vacuum should not exist. If vacuum exists, check throttle cable adjustment and go to next step. If vacuum does not exist, go to next step.
2. Open throttle slightly from idle. Vacuum should exist. If vacuum exists, go to next step. If vacuum does not exist, check throttle body port for clogging. Clean as necessary and go to next step.
3. Turn engine off. Check throttle cable for binding or sticking. If cable operation is okay, go to next step. If cable binds or sticks, check cable routing. Reroute or replace cable is necessary and go to next step.
4. Check throttle valve and shaft for being overly tight or loose. Replace throttle body as necessary. If throttle valve and shaft are okay, go to next step.
5. Check for clearance between throttle stop screw and throttle lever. If any clearance exists, replace throttle body. DO NOT adjust throttle stop screw.

Scheme 74

Ground Circuits

1. Measure resistance to ground at appropriate PCM ground terminals. See «POWER & GROUND CIRCUIT TERMINAL IDENTIFICATION»(ref-3110-S27957659022000041800000) table. Resistance should be zero ohms for each circuit. If resistance is not zero ohms, repair open to ground.
2. To check voltage drop on ground circuit, connect negative lead of DVOM to a good ground. Connect positive lead to each ground terminal. With engine running, voltmeter should indicate less than 0.1 volt. If voltage is more than 0.1 volt, check for open, corrosion, or loose connection on ground lead. See «WIRING DIAGRAMS»(ref-3123) article.

Power Circuits

1. Check for battery voltage between appropriate PCM connector Voltage Back-Up (VBU) terminal and ground. See «POWER & GROUND CIRCUIT TERMINAL IDENTIFICATION»(ref-3110-S27957659022000041800000) table. If battery voltage does not exist, check appropriate PCM fuse. See «PCM POWER CIRCUIT FUSE IDENTIFICATION»(ref-3110-S31682369442000041800000) table. If fuse is okay, check for an open in wire between fuse and appropriate PCM connector terminal. See «WIRING DIAGRAMS»(ref-3123) article.
2. Turn ignition on. Check for battery voltage between appropriate PCM connector Ignition Power (IGP) source terminal and ground. See «POWER & GROUND CIRCUIT TERMINAL IDENTIFICATION»(ref-3110-S27957659022000041800000) table. If battery voltage does not exist, check appropriate fuse. See «PCM POWER CIRCUIT FUSE IDENTIFICATION»(ref-3110-S31682369442000041800000) table. If fuse is okay, check for open in wire between fuse and appropriate PCM connector terminal. Check for defective ignition switch. See «WIRING DIAGRAMS»(ref-3123) article.

POWER & GROUND CIRCUIT TERMINAL IDENTIFICATION

PCM POWER CIRCUIT FUSE IDENTIFICATION

ENGINE SENSORS & SWITCHES

Many engine performance related sensors and switches will set a DTC if faulty. See appropriate SELF-DIAGNOSTICS article.

Accord M/T

1. Check No. 6 ECU (15-amp) fuse. Fuse is located in drivers side underdash fuse/relay box. Disconnect Vehicle Speed Sensor (VSS) 3-pin connector. VSS is located at lower right rear of engine, on top of transaxle. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Connect VSS Test Harness (07LAJ-PT3020A) to VSS harness connector. (Scheme 75) Connect positive ohmmeter probe to RED test harness clip. Tape all unused test harness clips to prevent contact with surrounding components. Check for continuity between Red test harness clip and ground. If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between VSS and ground connector. Ground connector is located at right side of plenum chamber, below Intake Air Temperature (IAT) sensor.
2. Connect positive voltmeter probe to White test harness clip, and connect negative voltmeter probe to Red test harness clip. (Scheme 75) Turn ignition on. Measure voltage between White and Red test harness clips. If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Black/Yellow wire between VSS and No. 6 ECU (15-amp) fuse.
3. Disconnect White test harness clip. Connect positive voltmeter probe to Green test harness clip. Measure voltage between Green and Red test harness clips. If 5 volts or more exists, go to next step. If 5 volts or more do not exist, repair short in Blue/White wire between VSS, PCM 31-pin connector "C" terminal No. 23, cruise control unit terminal No. 12 and driver's multiplex control unit connector "B" terminal No. 14. See «PIN VOLTAGE CHARTS»(ref-3080) article. (Scheme 76) Cruise control unit is located under instrument panel on left side of steering column. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Driver's multiplex control unit is located on driver's side underdash fuse/relay box.
4. Turn ignition off. Connect other end of VSS Test Harness (07LAJ-PT3020A) to VSS connector. Raise and support front of vehicle. Place transmission in Neutral and turn ignition on. Block one front wheel. While observing voltmeter, slowly rotate other front wheel. If voltage toggles between zero and about 5 volts or more, go to next step. If voltage does not toggle between zero and about 5 volts or more, replace VSS.
5. Disconnect instrument cluster 22-pin connector "B". Measure voltage between ground and instrument cluster 22-pin harness connector "B" terminal No. 2 (Blue/White wire). Ensure one front wheel is blocked. While observing voltmeter, slowly rotate other front wheel. If voltage is toggling, replace speedometer. If voltage is not toggling, repair open in Blue/White wire between VSS and instrument panel 22-pin connector "B". (Scheme 76)

Scheme 75

Scheme 76

Civic

1. Check No. 15 ALTERNATOR & SP SENSOR (7.5-amp). Fuse is located in underdash fuse/relay box. Disconnect VSS 3-pin connector. VSS is located at lower right rear of engine, on top of transaxle. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Connect VSS Test Harness (07LAJ-PT3020A) to VSS harness connector. (Scheme 75) Connect positive ohmmeter probe to RED test harness clip. Tape all unused test harness clips to prevent contact with surrounding components. Check for continuity between Red test harness clip and ground. If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between VSS and ground connector. On models not equipped with Continuously Variable Transmission (CVT), ground connector is located at right side of engine, below engine coolant temperature switch, on thermostat housing. On models equipped with CVT, ground connector is located at right front of engine, below air cleaner box.
2. On all models, connect positive voltmeter probe to White test harness clip, and connect negative voltmeter probe to Red test harness clip. (Scheme 75) Turn ignition on. Measure voltage between White and Red test harness clips. If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Black/Yellow wire between VSS and No. 15 ALTERNATOR & SP SENSOR fuse (7.5-amp).
3. Disconnect White test harness clip. Connect positive voltmeter probe to Green test harness clip. Measure voltage between Green and Red test harness clips. If 5 volts or more exists, go to next step. If less than 5 volts exists, repair open in Blue/White wire between VSS and PCM 31-pin connector "C" terminal No. 18 (D16Y5 engine with M/T) or terminal No. 23 (except D16Y5 engine with M/T), or cruise control unit (if equipped) connector terminal No. 12. See «PIN VOLTAGE CHARTS»(ref-3080) article. Cruise control unit is located behind driver's left kick panel. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000).
4. Turn ignition off. Connect other end of VSS Test Harness (07LAJ-PT3020A) to VSS connector. Raise and support front of vehicle. Turn ignition on and place transmission in Neutral. Block one front wheel. While observing voltmeter, slowly rotate other front wheel. If voltage toggles between zero and about 5 volts or more, go to next step. If voltage does not toggle between zero and about 5 volts or more, replace VSS.
5. Disconnect instrument cluster 16-pin connector "B". Measure voltage between ground and instrument cluster 16-pin harness connector "B" terminal No. 11 (Blue/White wire). Ensure one front wheel is blocked. While observing voltmeter, slowly rotate other front wheel. If voltage is toggling, replace speedometer. If voltage is not toggling, repair open in Blue/White wire between VSS and instrument panel 16-pin connector "B".

Scheme 77

CR-V

1. Check No. 15 ALTERNATOR & SP SENSOR (7.5-amp) fuse. Fuse is located in underdash fuse/relay box. Disconnect VSS 3-pin connector. VSS is located at lower right rear of engine, on top of transaxle. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Connect VSS Test Harness (07LAJ-PT30200 or 07LAJ-PT3020A) to VSS harness connector. (Scheme 75) Connect positive ohmmeter probe to RED test harness clip. Tape all unused test harness clips to prevent contact with surrounding components. Check for continuity between Red test harness clip and ground. If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between VSS and ground connector. Ground connector is located at lower right rear of engine, on thermostat housing.
2. Connect positive voltmeter probe to White test harness clip, and connect negative voltmeter probe to Red test harness clip. (Scheme 75) Turn ignition on. Measure voltage between White and Red test harness clips. If battery voltage exists, go to next step. If battery voltage does not exist, repair open in wire between VSS and No. 15 ALTERNATOR & SP SENSOR (7.5-amp) fuse.
3. Disconnect White test harness clip. Connect positive voltmeter probe to Green test harness clip. Measure voltage between Green and Red test harness clips. If 5 volts or more exists, go to next step. If 5 volts or more do not exist, repair short in Blue/White wire between VSS and PCM 31-pin connector "C" terminal No. 18, Transmission Control Module (TCM) 22-pin connector "B" terminal No. 5 (A/T) or cruise control unit connector terminal No. 12. See «PIN VOLTAGE CHARTS»(ref-3080) article.
4. Turn ignition off. Connect other end of VSS Test Harness (07LAJ-PT30200 or 07LAJ-PT3020A) to VSS connector. Raise and support front of vehicle. Place transmission in Neutral and turn ignition on. Block one front wheel. While observing voltmeter, slowly rotate other front wheel. If voltage toggles between zero volts and about 5 volts or more, go to next step. If voltage does not toggle between zero volts and about 5 volts or more, replace VSS.
5. Disconnect instrument cluster 16-pin connector "B". Measure voltage between ground and instrument cluster 16-pin harness connector "B" terminal No. 11 (Blue/White wire). Ensure one front wheel is blocked. While observing voltmeter, slowly rotate other front wheel. If voltage is toggling, replace speedometer. If voltage is not toggling, repair open in Blue/White wire between VSS and instrument panel 16-pin connector "B".

Prelude

1. Check No. 14 EAT ECU (15-amp) fuse. Fuse is located in underdash fuse/relay box. Disconnect VSS 3-pin connector. VSS is located at lower right rear of engine, on top of transaxle. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Connect VSS Test Harness (07LAJ-PT3020A) to VSS harness connector. (Scheme 75) Connect positive ohmmeter probe to RED test harness clip. Tape all unused test harness clips to prevent contact with surrounding components. Check for continuity between Red test harness clip and ground. If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between VSS and ground connector. Ground connector is located at right side of engine, below VTEC pressure switch and ignition coil secondary ignition wire.
2. On all models, connect positive voltmeter probe to White test harness clip, and connect negative voltmeter probe to Red test harness clip. (Scheme 75) Turn ignition on. Measure voltage between White and Red test harness clips. If battery voltage exists, go to next step. If battery voltage does not exist, repair open in wire between VSS and No. 14 EAT ECU (15-amp) fuse.
3. Disconnect White test harness clip. Connect positive voltmeter probe to Green test harness clip. Measure voltage between Green and Red test harness clips. If 5 volts or more exists, go to next step. If 5 volts or more do not exist, repair short in Blue/White wire between VSS and PCM 31-pin connector "C" terminal No. 18, Transmission Control Module (TCM) 22-pin connector "B" terminal No. 5 (A/T) or cruise control unit connector terminal No. 12. See «PIN VOLTAGE CHARTS»(ref-3080) article.
4. On all models, turn ignition off. Connect other end of VSS Test Harness (07LAJ-PT3020A) to VSS connector. Raise and support front of vehicle. Turn ignition on and place transmission in Neutral. Block one front wheel. While observing voltmeter, slowly rotate other front wheel. If voltage toggles between zero and about 5 volts or more, go to next step. If voltage does not toggle between zero and about 5 volts or more, replace VSS.
5. Disconnect instrument cluster 16-pin connector "B". Measure voltage between ground and instrument cluster 16-pin harness connector "B" terminal No. 3 (Blue/White wire). Ensure one front wheel is blocked. While observing voltmeter, slow rotate other front wheel. If voltage toggles between zero and about 5 volts or more replace speedometer. If voltage does not toggle between zero and about 5 volts or more, repair open in Blue/White wire between VSS and instrument panel 16-pin connector "B".

S2000

1. Raise and support vehicle. Disconnect VSS 3-pin connector. VSS is located at left side of transmission. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Check for continuity between ground and VSS harness connector terminal No. 3 (Brown/Yellow wire). If continuity exists, go to next step. If continuity does not exists, repair open in Brown/Yellow wire between VSS and ground connector G101. Ground connector G101 is located behind valve cover on engine block.
2. Disconnect Throttle Position (TP) sensor. Turn ignition on. Measure voltage between ground and VSS harness connector terminal No. 1 (Yellow/Blue wire). If about 5 volts exist, go to next step. If about 5 volts do not exist, repair short in Yellow/Blue wire between VSS and PCM 31-pin connect "C" terminal No. 28 or TP sensor. See «PIN VOLTAGE CHARTS»(ref-3080) article.
3. Measure voltage between ground and VSS harness connector terminal No. 2 (Blue/White wire). If about 5 volts exist, go to next step. If about 5 volts do not exist, repair open or short to ground in Blue/White wire between VSS and PCM 32-pin connector "A" terminal No. 9 or instrument cluster 20-pin connector "C" terminal No. 3. See «PIN VOLTAGE CHARTS»(ref-3080) article.
4. Reconnect VSS connector. Turn ignition on and place transmission in Neutral. Using backprobe set, measure voltage between ground and instrument cluster 20-pin connector "C" terminal No. 3 (Blue/White wire). (Scheme 78) If voltage toggles between zero and about 5 volts or more, replace printer circuit board in instrument cluster. If voltage does not toggle between zero and about 5 volts or more, replace VSS.

Scheme 78

Accord A/T

1. Check for DTC P0720. Repair as necessary. If DTC P0720 does not exist, check fuse No. 9 BACK-UP (7.5-amp). Fuse is located in driver's side underdash fuse/relay box. Using backprobe set, check for continuity between instrument cluster 22-pin connector "B" terminal No. 16 (Black wire) and ground connector G501. See «WIRING DIAGRAMS»(ref-3123) article. Ground connector G501 is located behind dash center panel. If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between instrument cluster 22-pin connector "B" and ground connector G501. (Scheme 76)
2. Raise and support front of vehicle. Disconnect instrument cluster 22-pin connector "B". Measure voltage between ground and instrument cluster 22-pin harness connector "B" terminal No. 2 (Blue/White wire). Turn ignition on and place transmission in Neutral. Block one front wheel. While observing voltmeter, rotate other front wheel more than 3 MPH. If voltage toggles between zero and about 5 volts or more, replace instrument cluster. If voltage does not toggle between zero and about 5 volts or more, go to next step.
3. Using backprobe set, measure voltage between ground and PCM 32-pin connector "A" terminal No. 9 (Blue/White wire). See «WIRING DIAGRAMS»(ref-3123) article. Ensure ignition switch is on and transmission is in Neutral. While observing voltmeter, rotate other front wheel more than 3 MPH. If voltage does not toggle between zero and about 5 volts or more, repair Blue/White wire between PCM 32-pin connector "A", cruise control unit terminal No. 12 and driver's side multiplex control unit 14-pin connector "B". Cruise control unit is located under instrument panel on left side of steering column. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Driver's multiplex control unit is located on driver's side underdash fuse/relay box. If voltage toggles between zero and about 5 volts or more, go to next step.
4. Disconnect PCM 32-pin connector "A". Check for continuity between ground and PCM 32-pin harness connector "A" terminal No. 9 (Blue/White wire). If continuity exists, repair short in Blue/White wire between PCM 32-pin connector "A", gauge assembly 22-pin connector "B" terminal No. 2, cruise control unit and driver's side multiplex control unit. If continuity does not exist, check for bent, loose or corroded terminals. If terminals are okay, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or problem goes away, replace original PCM.

Odyssey

1. Check for DTC P0720. Repair as necessary. If DTC P0720 does not exist, check No. 9 BACK-UP (10-amp) fuse. Fuse is located in driver's side underdash fuse/relay box. Using backprobe set, check for continuity between instrument cluster 22-pin connector "B" terminal No. 16 (Black wire) and ground connector G503. See «WIRING DIAGRAMS»(ref-3123) article. Ground connector G503 is located at right side of dash, behind glove box, above keyless door lock control unit. If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between instrument cluster 22-pin connector "B" and ground connector G503. (Scheme 76)
2. Raise and support front of vehicle. Disconnect instrument cluster 22-pin connector "B". Measure voltage between ground and instrument cluster 22-pin harness connector "B" terminal No. 2 (Blue/White wire). Turn ignition on and place transmission in Neutral. Block one front wheel. While observing voltmeter, rotate other front wheel more than 3 MPH. If voltage toggles between zero and about 5 volts or more, replace instrument cluster. If voltage does not toggle between zero and about 5 volts or more, go to next step.
3. Using backprobe set, measure voltage between ground and PCM 32-pin connector "A" terminal No. 9 (Blue/White wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. Block one front wheel. While observing voltmeter, rotate other front wheel more than 3 MPH. If voltage toggles between zero and about 5 volts or more, repair Blue/White wire between PCM 32-pin connector "A" and instrument cluster 22-pin connector "B" terminal No. 2. If voltage does not toggle between zero volts and about 5 volts or more, go to next step.
4. Disconnect PCM 32-pin connector "A". Check for continuity between ground and PCM 32-pin harness connector "A" terminal No. 9 (Blue/White wire). If continuity exists, repair short in Blue/White wire between PCM 32-pin connector "A" and instrument cluster, cruise control connector terminal No. 12 or driver's multiplex control unit 22-pin connector "B" terminal No. 14. If continuity does not exist, check for bent, loose or corroded terminals. If terminals are okay, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or problem goes away, replace original PCM.

Accord & Odyssey

1. Turn ignition off. Remove PGM-FI main relay. PGM-FI main relay is located under left side of instrument panel, near steering column. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Check for continuity between ground and PGM-FI main relay harness connector terminal No. 3 (Black wire). (Scheme 79) If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between PGM-FI main relay connector terminal No. 3 and ground connection. Go to next step.
2. On Accord 2.3L, ground connection is located at left side of intake plenum, under Intake Air Temperature (IAT) sensor. On Accord V6 and Odyssey, ground connection is located left side of engine, on thermostat housing, below radiator fan switch. See «WIRING DIAGRAMS»(ref-3123) article. Go to next step.
3. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 7 (White/Green wire). If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 46 ACG-S (15-amp) fuse. No. 46 ACG-S (15-amp) fuse is located at under-hood fuse/relay box. If fuse is blown, check for short in White/Green wire between No. 46 ACG-S (15-amp) fuse and PGM-FI main relay. If fuse is okay, check for open in White/Green wire between No. 46 ACG-S (15-amp) fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article.
4. Turn ignition on. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 5 (Red/White wire). If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 1 FUEL PUMP (15-amp) fuse. No. 1 FUEL PUMP (15-amp) fuse is located in driver's side under-dash fuse/relay box. If fuse is blown, check for short in Red/White wire between No. 1 FUEL PUMP (15-amp) fuse and PGM-FI main relay. If fuse is okay, check for open in Red/White wire between No. 1 FUEL PUMP (15-amp) fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article.
5. Put transmission in Park (A/T) or depress clutch pedal (M/T). Turn ignition switch to START position. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 2 (Blue/Orange wire). If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 13 STARTER SIGNAL (7.5-amp) fuse. No. 13 STARTER SIGNAL (7.5-amp) fuse is located in driver's side under-dash fuse/relay box. If fuse is blown, check for short in Blue/Orange wire between No. 13 STARTER SIGNAL (7.5-amp) fuse and PGM-FI main relay. If fuse is okay, check for open in Blue/Orange wire between No. 13 STARTER SIGNAL (7.5-amp) fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article.
6. Turn ignition off. Disconnect PCM 32-pin connector "A". Check for continuity in Green/Yellow wire between PGM-FI main relay harness connector terminal No. 1 and PCM 32-pin harness connector "A" terminal No. 15. If continuity exists, go to next step. If continuity does not exist, repair open in Green/Yellow wire between PGM-FI main relay and PCM 32-pin connector "A". See «WIRING DIAGRAMS»(ref-3123) article.
7. Reconnect PCM and PGM-FI main relay connectors. Turn ignition on. On Accord, using backprobe set, measure voltage between PCM 25-pin connector "B" terminals No. 1 (Yellow/Black wire) and No. 20 (Brown/Black wire), and between No. 9 (Yellow/Black wire) and No. 20 (Brown/Black wire). On Odyssey, using backprobe set, measure voltage between PCM 25-pin connector "B" terminals No. 1 (Yellow/Black wire) and No. 2 (Black wire), and between No. 9 (Yellow/Black wire) and No. 2 (Black wire). Go to next step.
8. On all models, if battery voltage exists, go to next step. If battery voltage does not exist, repair open in Yellow/Black wire between PCM 25-pin connector "B" terminal No. 1 or No. 9 and PGM-FI main relay terminal No. 6. See «WIRING DIAGRAMS»(ref-3123) article. If wires are okay, replace PGM-FI main relay.
9. Turn ignition off. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 15 (Green/Yellow wire) and 25-pin connector "B" terminal No. 2 (Black wire). Turn ignition on. If one volt or less exists for 2 seconds after ignition is first turned on, check PGM-FI main relay. See «PGM-FI MAIN RELAY TEST»(ref-3110-S32986050582000041800000). If more than one volt exists, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.

Civic & CR-V

1. Turn ignition off. Remove PGM-FI main relay. PGM-FI main relay is located under right side of instrument panel, above passenger's right kick panel. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Check for continuity between ground and PGM-FI main relay harness connector terminal No. 3 (Black wire). (Scheme 79) If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between PGM-FI main relay connector terminal No. 3 and ground connection. Go to next step.
2. On Civic except Continuously Variable Transmission (CVT), ground connection is located on right side of engine, on thermostat housing, under engine coolant temperature switch. On Civic equipped with CVT, ground connection is located at right front of engine between air cleaner box and starter. On CR-V, ground connection is located behind distributor next to radiator fan switch. See «WIRING DIAGRAMS»(ref-3123) article. Go to next step.
3. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 7 (White/Black wire). See «WIRING DIAGRAMS»(ref-3123) article. If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short in White/Black wire between No. 44 FI E/M (15-amp) fuse and PGM-FI main relay. If wire is okay, replace No. 44 FI E/M (15-amp) fuse in under-hood fuse/relay box. See «WIRING DIAGRAMS»(ref-3123) article.
4. Turn ignition on. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 5 (Yellow/Green wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short in Yellow/Green wire between No. 13 FUEL PUMP (15-amp) fuse and PGM-FI main relay, or replace No. 13 FUEL PUMP (15-amp) fuse in under-dash fuse/relay box. See «WIRING DIAGRAMS»(ref-3123) article.
5. Put transmission in Park (A/T) or depress clutch pedal (M/T). Turn ignition switch to START position. Measure voltmeter between ground and PGM-FI main relay harness connector terminal No. 2 (Blue/White wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short in Blue/White wire between No. 31 STARTER SIGNAL (7.5-amp) fuse and PGM-FI main relay, or replace No. 31 STARTER SIGNAL (7.5-amp) fuse in under-dash fuse/relay box. See «WIRING DIAGRAMS»(ref-3123) article.
6. Turn ignition off. Disconnect PCM 32-pin connector "A". Check for continuity in Green/Yellow wire between PGM-FI main relay harness connector terminal No. 1 and PCM 32-pin harness connector "A" terminal No. 16. See «PIN VOLTAGE CHARTS»(ref-3080) article. If continuity exists, go to next step. If continuity does not exist, repair open in Green/Yellow wire between PGM-FI main relay and PCM 32-pin connector "A".
7. Reconnect PCM and PGM-FI main relay connectors. Turn ignition on. On Civic, using backprobe set, measure voltage between PCM 25-pin connector "B" terminals No. 1 (Yellow/Black wire) and No. 20 (Brown/Black wire), and between No. 9 (Yellow/Black wire) and No. 20 (Brown/Black wire). On CR-V, using backprobe set, measure voltage between PCM 25-pin connector "B" terminals No. 1 (Yellow/Black wire) and No. 2 (Black wire), and between No. 9 (Yellow/Black wire) and No. 2 (Black wire). Go to next step.
8. On all models, if battery voltage exists, go to next step. If battery voltage does not exist, repair open in Yellow/Black wire between PCM 25-pin connector "B" terminal No. 1 or No. 9 and PGM-FI main relay terminal No. 6. See «WIRING DIAGRAMS»(ref-3123) article. If wires are okay, replace PGM-FI main relay.
9. Turn ignition off. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 16 (Green/Yellow wire) and 25-pin connector "B" terminal No. 2 (Black wire). Turn ignition on. If one volt or less exists for 2 seconds after ignition is first turned on, check PGM-FI main relay. See «PGM-FI MAIN RELAY TEST»(ref-3110-S32986050582000041800000). If more than one volt exists, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.

1. Turn ignition off. Remove PGM-FI main relay. PGM-FI main relay is located under left side of instrument panel, near steering column. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Check for continuity between ground and PGM-FI main relay harness connector terminal No. 3 (Black wire). (Scheme 79) If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between PGM-FI main relay connector terminal No. 3 and ground connection. Ground connection is located below and behind distributor cap, under VTEC pressure switch. See «WIRING DIAGRAMS»(ref-3123) article.
2. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 7 (White/Green wire). See «WIRING DIAGRAMS»(ref-3123) article. If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 4 ACG-S (10-amp) fuse in fuse/relay box located on left side of engine compartment, next to battery. If fuse is blown, check for a short in White/Green wire between PGM-FI main relay and No. 4 ACG S (15-amp) fuse. If fuse is okay, check for open in White/Green wire between PGM-FI main relay and No. 4 ACG S (15-amp) fuse. See «WIRING DIAGRAMS»(ref-3123) article.
3. Turn ignition on. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 5 (Red/Orange wire). If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 23 FUEL PUMP SRS (15-amp) fuse in under-dash fuse/relay box. If fuse is blown, check for short in Red/Orange wire between No. 23 FUEL PUMP SRS (15-amp) fuse and PGM-FI main relay. If fuse is okay, check for open in Red/Orange wire between No. 23 FUEL PUMP SRS (15-amp) fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article.
4. Depress clutch pedal. Turn ignition switch to START position. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 2 (Blue/Red wire). If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 2 STARTER SIGNAL (7.5-amp) fuse in under-dash fuse/relay box. If fuse is blown, check for short in Blue/Red wire between No. 2 STARTER SIGNAL (7.5-amp) fuse and PGM-FI main relay. If fuse is okay, check for open in Blue/Red wire between No. 2 STARTER SIGNAL (7.5-amp) fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article.
5. Turn ignition off. Disconnect PCM 32-pin connector "A". Check for continuity in Green/Orange wire between PGM-FI main relay harness connector terminal No. 1 and PCM 32-pin harness connector "A" terminal No. 16. See «PIN VOLTAGE CHARTS»(ref-3080) article. If continuity exists, go to next step. If continuity does not exist, repair open in Green/Orange wire between PGM-FI main relay and PCM 32-pin connector "A". See «WIRING DIAGRAMS»(ref-3123) article.
6. Reconnect PCM and PGM-FI main relay connectors. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 10 (Black wire) and No. 11 (Yellow/Black wire), and between No. 10 (Black wire) and No. 24 (Yellow/Black wire). If battery voltage exists, go to step 7. If battery voltage does not exist, repair open in Yellow/Black wire between PCM 32-pin connector "A" terminal No. 11 or No. 24 and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article. If wires are okay, replace PGM-FI main relay.
7. Turn ignition off. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 10 (Black wire) and No. 16 (Green/Orange wire). Turn ignition on. If one volt or less exists for 2 seconds after ignition is first turned on, check PGM-FI main relay. See «PGM-FI MAIN RELAY TEST»(ref-3110-S32986050582000041800000). If more than one volt exists, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.

1. Turn ignition off. Remove PGM-FI main relay. PGM-FI main relay is located at right side of steering column. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Check for continuity between ground and PGM-FI main relay harness connector terminal No. 3 (Black wire). (Scheme 79) If continuity exists, go to next step. If continuity does not exist, repair open in Black wire between PGM-FI main relay connector terminal No. 3 and ground connection. Ground connection is located at rear of engine, behind cylinder head. See «WIRING DIAGRAMS»(ref-3123) article.
2. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 7 (White/Green wire). See «WIRING DIAGRAMS»(ref-3123) article. If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 46 ACG S (15-amp) fuse in under-dash fuse/relay box. If fuse is blown check for a short in White/Green wire between PGM-FI main relay and No. 46 ACG S (15-amp) fuse. If fuse is okay, check for open in White/Green wire between PGM-FI main relay and No. 46 ACG S (15-amp) fuse. See «WIRING DIAGRAMS»(ref-3123) article.
3. Turn ignition on. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 5 (Black/Yellow wire). If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 2 FUEL PUMP SRS (15-amp) fuse in under-dash fuse/relay box. If fuse is blown, check for short in Black/Yellow wire between No. 2 FUEL PUMP SRS (15-amp) fuse and PGM-FI main relay. If fuse is okay, check for open in Black/Yellow wire between No. 2 FUEL PUMP SRS (15-amp) fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article.
4. Depress clutch pedal. Turn ignition switch to ON position. Push start button. Measure voltage between ground and PGM-FI main relay harness connector terminal No. 2 (Blue/Orange wire). If battery voltage exists, go to next step. If battery voltage does not exist, check for a blown No. 21 STARTER SIGNAL (7.5-amp) fuse in under-dash fuse/relay box. If fuse is blown, check for short in Blue/Orange wire between No. 21 STARTER SIGNAL (7.5-amp) fuse and PGM-FI main relay. If fuse is okay, check for open in Blue/Orange wire between No. 21 STARTER SIGNAL (7.5-amp) fuse and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article.
5. Turn ignition off. Disconnect PCM 32-pin connector "A". Check for continuity in Green/Yellow wire between PGM-FI main relay harness connector terminal No. 1 and PCM 32-pin harness connector "A" terminal No. 15. See «PIN VOLTAGE CHARTS»(ref-3080) article article. If continuity exists, go to next step. If continuity does not exist, repair open in Green/Yellow wire between PGM-FI main relay and PCM 32-pin connector "A". See «WIRING DIAGRAMS»(ref-3123) article.
6. Reconnect PCM and PGM-FI main relay connectors. Turn ignition on. Using backprobe set, measure voltage between PCM 25-pin connector "B" terminals No. 1 (Yellow/Black wire) and No. 20 (Brown/Yellow wire), and between No. 9 (Yellow/Black wire) and No. 20 (Brown/Yellow wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open in Yellow/Black wire between PCM 25-pin connector "B" terminals No. 1 or No. 9 and PGM-FI main relay. See «WIRING DIAGRAMS»(ref-3123) article. If wires are okay, replace PGM-FI main relay.
7. Turn ignition off. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 15 (Green/Yellow wire) and PCM 25-pin connector "B" terminal No. 2 (Black wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. Turn ignition on. If one volt or less exists for 2 seconds after ignition is first turned on, check PGM-FI main relay. See «PGM-FI MAIN RELAY TEST»(ref-3110-S32986050582000041800000). If more than one volt exists, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.

Scheme 79

VTEC SOLENOID VALVE

Check for resistance between ground and VTEC solenoid valve connector terminal No. 1. If resistance is not 14-30 ohms, replace VTEC solenoid valve. If resistance is 14-30 ohms, remove VTEC solenoid valve assembly from cylinder head. Check VTEC solenoid valve filter for clogging. If clogging is found, replace engine oil and filter. If filter is not clogged, push VTEC solenoid valve pintle with finger to check movement. If VTEC solenoid valve pintle does not move freely, replace VTEC solenoid valve. If VTEC solenoid valve pintle moves freely, check engine oil pressure.

FUEL DELIVERY

Note. For fuel system pressure testing, see BASIC DIAGNOSTIC PROCEDURES article.

Fuel Pump (Accord, CR-V, Odyssey & S2000)

1. On Accord, CR-V and S2000, check fuel pump operation by listening for noise at fuel fill port with cap removed. On Odyssey, check fuel pump operation by listening for noise at fuel injector rails located under intake manifold cover. On all models, fuel pump should run for 2 seconds after ignition switch is first turned to ON position. If fuel pump does not make any noise, go to next step.
2. On Accord, remove spare tire cover. On CR-V, fold left rear seat cushion forward and remove base frame cover. On Odyssey, remove rear seats and pull back carpet. On S2000, remove tray trim and tray from behind head rests. On all models, remove fuel pump access panel. Ensure ignition is off. Disconnect fuel pump 5-pin connector. Using backprobe set, connect a fused jumper wire between PGM-FI main relay 7-pin connector terminals No. 4 (Black/Yellow wire on Accord and Odyssey or Yellow/Green wire on CR-V and S2000) and No. 5 (Red/White wire on Accord and Odyssey, Yellow/Green wire on CR-V or Black/Yellow wire on S2000). (Scheme 79) Go to next step.
3. Turn ignition on. Check for battery voltage between ground and fuel pump 5-pin harness connector terminal No. 5 (Black/Yellow wire) on Accord and Odyssey, No. 4 (Yellow/Green wire) on CR-V or No. 5 (Yellow/Green wire) on S2000 as soon as ignition is turned on. On all models, go to next step.
4. If battery voltage exists, check for open in Black wire between fuel pump harness 5-pin connector terminal No. 4 (Accord, Odyssey or S2000) or No. 3 (CR-V) and ground connector. On Accord, ground connector is located in left front of fuel pump access panel. On CR-V, ground connector is located at left front door sill. Go to next step. On Odyssey, ground connector is located at bottom of left center pillar, in front of driver's seat belt tensioner. On S2000, ground connector is located at left front of trunk, behind carpet. Go to next step.
5. On all models, if Black wire is okay, replace fuel pump. If battery voltage does not exist, check PGM-FI main relay and circuit. See «PGM-FI MAIN RELAY TEST»(ref-3110-S32986050582000041800000) and «PGM-FI MAIN RELAY CIRCUIT CHECK»(ref-3110-S14687767612000053000000).

Fuel Pump (Civic & Prelude)

1. Check fuel pump operation by listening for noise at fuel fill port with cap removed. Fuel pump should run for 2 seconds after ignition switch is first turned to ON position. If fuel pump does not make any noise, go to next step.
2. Remove rear seat cushion hold down bolt located behind cushion and remove rear seat cushion. Pull back carpet. Remove fuel pump access panel. Ensure ignition is off. Disconnect fuel pump 2-pin connector. Using backprobe set, connect a fused jumper wire between PGM-FI main relay 7-pin connector terminals No. 4 (Black/Yellow wire on Prelude or Yellow/Green wire on Civic) and No. 5 (Yellow/Green wire on Civic or Red/Orange wire on Prelude). (Scheme 79) Go to next step.
3. Turn ignition on. Check for battery voltage between ground and fuel pump 2-pin harness connector terminal No. 2 (Yellow/Green wire on Civic or Black/Yellow wire on Prelude) as soon as ignition is turned on. On all models, go to next step.
4. If battery voltage exists, check for open in Black wire between fuel pump harness 2-pin connector terminal No. 1 and ground connector. On Civic, ground connector is located at left front door sill. Go to next step. On Prelude, ground connector is located under front passenger's seat. Go to next step.
5. On all models, if Black wire is okay, replace fuel pump. If battery voltage does not exist, check PGM-FI main relay and circuit. See «PGM-FI MAIN RELAY TEST»(ref-3110-S32986050582000041800000) and «PGM-FI MAIN RELAY CIRCUIT CHECK»(ref-3110-S14687767612000053000000).

Fuel Injector

Fuel injector resistance information is not available from manufacturer. For fuel injector testing, see appropriate MISFIRE IN ONE CYLINDER DETECTED DTC testing in appropriate SELF-DIAGNOSTICS article.

Fuel Pressure Regulator

Disconnect fuel pressure regulator vacuum hose. Check fuel system pressure. See FUEL PRESSURE in BASIC DIAGNOSTIC PROCEDURES article. Reconnect and again disconnect fuel pressure regulator vacuum hose. Ensure fuel pressure rises when vacuum hose is disconnected. If fuel pressure does not rise and fall as specified, replace fuel pressure regulator.

AIR CONDITIONING SIGNAL

Note. This signal informs PCM of a demand for A/C system.

Accord, Odyssey & S2000

1. Turn ignition off. Disconnect A/C pressure switch connector. See «A/C SIGNAL COMPONENT LOCATIONS»(ref-3110-S32264581282000041800000) table. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 27 (Blue/Red wire) and 25-pin connector "B" terminal No. 20 (Brown/Black wire on Accord and Odyssey, or Brown/Yellow wire on S2000). See «PIN VOLTAGE CHARTS»(ref-3080) article. If 5 volts exist, go to next step. If 5 volts do not exist, go to step 4.
2. Turn ignition off. Reconnect A/C pressure switch connector. Turn ignition on. Using backprobe set, momentarily connect a fused jumper wire between PCM 32-pin connector "A" terminals No. 17 (Red wire) and 25-pin connector "B" terminal No. 20 (Brown/Black wire on Accord and Odyssey, or Brown/Yellow wire on S2000), several times. If A/C compressor clutch makes a clicking sound, go to next step. If A/C compressor clutch does not make a clicking sound, go to step 5.
3. Start engine. Turn A/C and blower motor switches on. If A/C operates, A/C signal is okay. If A/C does not operate, go to step 7.
4. Turn ignition switch off. Disconnect PCM 32-pin connector "A". Check for continuity between ground and terminals PCM 32-pin harness connector "A" terminal No. 27 (Blue/Red wire). If continuity exists, repair short in Blue/Red wire between PCM 32-pin connector "A" and A/C pressure switch. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM. If continuity still does not exist, inspect A/C system. See appropriate article in AIR CONDITIONING & HEATING.
5. Using backprobe set, momentarily connect a fused jumper wire between ground and main (S2000) under-hood fuse/relay box 16-pin connector terminal No. 11 (Red wire), several times. (Scheme 80) Go to next step.
6. If A/C compressor clutch makes a clicking sound, repair open in Red wire between A/C clutch relay and PCM 32-pin connector "A" terminal No. 17. See «WIRING DIAGRAMS»(ref-3123) article. If A/C compressor clutch does not make a clicking sound, inspect A/C system. See appropriate A/C-HEATER SYSTEMS article.
7. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 27 (Blue/Red wire) and 25-pin connector "B" terminal No. 20 (Brown/Black wire on Accord and Odyssey, or Brown/Yellow on S2000). If less than one volt does not exist, repair open in Blue/Red wire between A/C pressure switch and PCM 32-pin connector "A". If less than one volt exists, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM. If specified voltage still does not exist, inspect A/C system. See appropriate A/C-HEATER SYSTEMS article.

Civic (Except D16Y5 Engine With M/T) & CR-V

1. Turn ignition off. Disconnect A/C pressure switch connector. See «A/C SIGNAL COMPONENT LOCATIONS»(ref-3110-S32264581282000041800000) table. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 27 (Blue/Red wire) and 25-pin connector "B" terminals No. 20 (Brown/Black wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If battery voltage exists, go to step 3. If battery voltage does not exist, go to next step.
2. Turn ignition switch off. Disconnect PCM 32-pin connector "A". Check for continuity between ground and PCM 32-pin harness connector "A" terminal No. 27 (Blue/Red wire). If continuity exists, repair short in Blue/Red wire between PCM 32-pin connector "A" and A/C pressure switch. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM. If continuity still does not exist, inspect A/C system. See appropriate A/C-HEATER SYSTEMS article.
3. Turn ignition off. Reconnect A/C pressure switch connector. Turn ignition on. Using backprobe set, momentarily connect a fused jumper wire between PCM 32-pin connector "A" terminal No. 17 (Black/Red wire) and PMC 25-pin connector "B" terminal No. 20 (Brown/Black wire), several times. If A/C compressor clutch makes a clicking sound, go to step 5. If A/C compressor clutch does not make a clicking sound, go to next step.
4. Using backprobe set, momentarily connect a fused jumper wire between ground and under-hood fuse/relay box 9-pin connector terminal No. 5 (Black/Red wire), several times. (Scheme 81) See «A/C SIGNAL COMPONENT LOCATIONS»(ref-3110-S32264581282000041800000) table. If A/C compressor clutch makes a clicking sound, repair open in Black/Red wire between PCM 32-pin connector "A" terminal No. 17 and under-hood fuse/relay box 9-pin connector terminal No. 5. See «WIRING DIAGRAMS»(ref-3123) article. If A/C compressor clutch does not make a clicking sound, inspect A/C system. See appropriate A/C-HEATER SYSTEMS article.
5. Start engine. Turn A/C and blower motor switches on. If A/C operates, A/C signal is okay. If A/C does not operate, go to next step.
6. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 27 (Blue/Red wire) and 25-pin connector "B" terminal No. 20 (Brown/Black wire). If less than one volt does not exist, repair open in Blue/Red wire between A/C pressure switch and PCM 32-pin connector "A". If less than one volt exists, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM. If specified voltage still does not exist, inspect A/C system. See appropriate A/C-HEATER SYSTEMS article.

Civic (D16Y5 Engine With M/T) & Prelude

1. Turn ignition off. Disconnect A/C pressure switch and A/C diode (Prelude) connectors. See «A/C SIGNAL COMPONENT LOCATIONS»(ref-3110-S32264581282000041800000) table. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and 31-pin connector "C" terminals No. 5 (Blue/Red wire on Civic, or Blue/Orange on Prelude). See «PIN VOLTAGE CHARTS»(ref-3080) article. If 5 volts (Civic) or battery voltage (Prelude) exists, go to step 3. If specified voltage does not exist, go to next step.
2. Turn ignition switch off. Disconnect PCM 31-pin connector "C". Check for continuity between ground and PCM 31-pin harness connector "C" terminal No. 5 (Blue/Red wire on Civic, or Blue/Orange on Prelude). If continuity exists, repair short in Blue/Red wire between PCM 31-pin connector "C" and A/C pressure switch. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM. If continuity still does not exist, inspect A/C system. See appropriate A/C-HEATER SYSTEMS article.
3. Turn ignition off. Reconnect A/C pressure switch and A/C diode (Prelude) connectors. Turn ignition on. Using backprobe set, momentarily connect a fused jumper wire between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and No. 17 (Black/Red wire on Civic, or Pink/Blue wire on Prelude), several times. If A/C compressor clutch makes a clicking sound, go to step 5. If A/C compressor clutch does not make a clicking sound, go to next step.
4. On Civic, using backprobe set, momentarily connect a fused jumper wire between ground and under-hood fuse/relay box 9-pin connector terminal No. 5 (Black/Red wire), several times. (Scheme 81) On Prelude, using backprobe set, momentarily connect a fused jumper wire between ground and A/C clutch relay connector terminal No. 4 (Pink/Blue wire), several times. (Scheme 82) See «A/C SIGNAL COMPONENT LOCATIONS»(ref-3110-S32264581282000041800000) table. On all models, if A/C compressor clutch makes a clicking sound, repair open in Black/Red wire (Civic) or Pink/Blue wire (Prelude) between PCM 32-pin connector "A" terminal No. 17 and under-hood fuse/relay box 9-pin connector terminal No. 5 on Civic, or A/C clutch relay on Prelude. See «WIRING DIAGRAMS»(ref-3123) article. If A/C compressor clutch does not make a clicking sound, inspect A/C system. See appropriate A/C-HEATER SYSTEMS article.
5. Start engine. Turn A/C and blower motor switches on. If A/C operates, A/C signal is okay. If A/C does not operate, go to next step.
6. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 5 (Blue/Red wire on Civic, or Blue/Orange on Prelude). If less than one volt does not exist, repair open in Blue/Red (Civic) wire or Blue/Orange (Prelude) wire between A/C pressure switch and PCM 31-pin connector "C". If less than one volt exists, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM. If specified voltage still does not exist, inspect A/C system. See appropriate A/C-HEATER SYSTEMS article.

A/C SIGNAL COMPONENT LOCATIONS

Scheme 80

Scheme 81

Scheme 82

A/T GEAR POSITION SIGNAL

Note. This signal informs PCM when transmission is in Park or Neutral.

Note. For A/T gear position signal testing on Accord, CR-V and Odyssey, see DTC P1705 or P1706: A/T GEAR POSITION SWITCH in appropriate SELF-DIAGNOSTICS article.

1. Turn ignition on. Observe A/T position indicator on instrument panel while selecting each gear position separately. If A/T position indicator functions properly, go to next step. If A/T position indicator does not function properly, see appropriate article in AUTOMATIC TRANSMISSIONS.
2. Turn ignition off. Disconnect instrument cluster 16-pin (Prelude) or 14-pin (Civic) connector. Disconnect Transmission Control Module (TCM) 26-pin connector. On Prelude, TCM is located in passenger side footwell, next to PCM. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000) . On Civic, TCM is located behind passenger side kick panel. On all models, turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and 32-pin connector "C" terminal No. 29 (Light Green wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If about 5 volts does not exist, go to next step. If about 5 volts exists, go to step 4 .
3. Turn ignition off. Disconnect PCM 31-pin connector "C". Check for continuity between ground and PCM 31-pin connector "C" terminal No. 29 (Light Green wire. See «PIN VOLTAGE CHARTS»(ref-3080) article. If continuity exists, repair short in Light Green wire between PCM 31-pin connector "C" and instrument cluster. See appropriate wiring diagram in WIRING DIAGRAMS article. If continuity does not exist, substitute a known-good PCM and recheck. On Prelude, see SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.
4. Turn ignition off. Reconnect instrument cluster and TCM connectors. Place transmission in Park or Neutral position. Start engine. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and PCM 31-pin connector "C" terminal No. 29 (Light Green wire). If less than one volt exists, go to next step. If less than one volt does not exist, repair open in Light Green wire between PCM 31-pin connector "C" and instrument cluster.
5. Measure voltage between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and terminal PCM 31-pin connector "C" terminal No. 29 (Light Green wire) with transmission in any position except Park or Neutral. If battery voltage on Civic, or 5 volts or more on Prelude exists, A/T gear position signal is okay. If specified voltage does not exist, repair short in Light Green wire between PCM 31-pin connector "C" and instrument cluster. See «WIRING DIAGRAMS»(ref-3123) article.

BRAKE SWITCH SIGNAL

Note. This signal informs PCM when brake pedal is depressed.

Accord, Civic (Except D16Y5 Engine With M/T), CR-V, Odyssey & S2000

1. Check brake lights. If brake lights are on without depressing brake pedal, check brake light switch and repair or replace as necessary. If brake lights are not on, depress brake pedal. If brake lights come on, go to next step. If brake lights do not come on, go to step 3 .
2. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 32 (White/Black wire on Accord, Odyssey and S2000, or Green/White wire on Civic and CR-V) and 25-pin connector "B" terminal No. 20 (Brown/Black wire), with brake pedal depressed. See «PIN VOLTAGE CHARTS»(ref-3080) article. If battery voltage exists, brake switch signal is okay. If battery voltage does not exist, repair open in White/Black wire (Accord, Odyssey and S2000) or Green/White wire (Civic and CR-V) between brake switch and PCM 32-pin connector "A". See «WIRING DIAGRAMS»(ref-3123) article.
3. Check brake switch fuse. See «BRAKE SWITCH FUSE IDENTIFICATION»(ref-3110-S03111067732000060200000) table. Fuse is located in under-hood fuse/relay box (main under-hood fuse/relay box on S2000). If fuse is okay, repair open in White/Yellow wire (Accord and Odyssey), Green/White wire (Civic and CR-V) or White/Green wire (S2000) between brake switch fuse and brake switch. If wire is okay, check brake switch adjustment. See ADJUSTMENTS in appropriate DISC & DRUM article in BRAKES. Adjust or replace brake switch as necessary. If fuse is not okay, repair short in White/Yellow wire (Accord and Odyssey), Green/White wire (Civic and CR-V) or White/Green wire (S2000) between brake switch fuse and brake switch. See «WIRING DIAGRAMS»(ref-3123) article. Repair as necessary.

1. Check brake lights. If brake lights are on without depressing brake pedal, check brake light switch and repair or replace as necessary. If brake lights are not on, depress brake pedal. If brake lights come on, go to next step. If brake lights do not come on, go to step 3 .
2. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and PCM 16-pin connector "D" terminal No. 5 (Green/White wire on Civic or White/Black wire on Prelude), with brake pedal depressed. See «PIN VOLTAGE CHARTS»(ref-3080) article. If battery voltage exists, brake switch signal is okay. If battery voltage does not exist, repair open in Green/White wire on Civic or White/Black wire on Prelude between brake switch and PCM 16-pin connector "D". See «WIRING DIAGRAMS»(ref-3123) article.
3. Check brake switch fuse. See «BRAKE SWITCH FUSE IDENTIFICATION»(ref-3110-S03111067732000060200000) table. Fuse is located in under-hood fuse/relay box. If fuse is okay, repair open in White/Green wire on Civic or White/Black wire on Prelude between brake switch fuse and brake switch. If wire is okay, check brake switch adjustment. See ADJUSTMENTS in appropriate DISC & DRUM article in BRAKES. Adjust or replace brake switch as necessary. If fuse is not okay, repair short in White/Green wire (Civic) or White/Black wire (Prelude) wire between brake switch fuse and brake switch. See «WIRING DIAGRAMS»(ref-3123) article. Repair as necessary.

BRAKE SWITCH FUSE IDENTIFICATION

CLUTCH SWITCH SIGNAL (CIVIC D16Y5 ENGINE WITH M/T)

Note. This signal informs PCM when clutch is engaged.

1. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 29 (Red wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. see scheme 44 If about 5 volts exists, go to step 4. If about 5 volts does exist, go to next step.
2. Turn ignition off. Disconnect clutch switch 2-pin connector. Clutch switch is located above clutch pedal. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Turn ignition on. Measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 29 (Red wire). If about 5 volts exists, replace clutch switch. If about 5 volts does not exist, go to next step.
3. Turn ignition off. Disconnect PCM 31-pin connector "C". Check for continuity between ground and PCM 31-pin harness connector "C" terminal No. 29 (Red wire). If continuity exists, repair short in Red wire between PCM 31-pin connector "C" and clutch switch. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.
4. Depress clutch pedal. Measure voltage between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 29 (Red wire). If less than one volt exists, clutch switch signal is okay. If about one volt does not exist, go to next step.
5. Turn ignition off. Disconnect clutch switch 2-pin connector. Clutch switch is located above clutch pedal. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000). Depress clutch pedal and check for continuity between clutch switch terminals. If continuity exists, go to next step. If continuity does not exist, adjust or replace clutch switch.
6. Turn ignition on. Measure voltage between ground and clutch switch harness connector No. 1 (Red wire). If about 5 volts exists, repair open in Black wire between clutch switch harness connector and ground connection. Ground connection is located behind left kick panel, left of clutch switch, behind cruise control unit. See «WIRING DIAGRAMS»(ref-3123) article. If about 5 volts does not exist, repair open in Red wire between PCM 31-pin connector "C" and clutch switch. See «WIRING DIAGRAMS»(ref-3123) article.

GENERATOR (GEN) FR SIGNAL

Note. This signal informs PCM when generator is charging.

Accord, Civic (Except D16Y5 Engine With M/T), CR-V & Odyssey

1. Turn ignition off. Disconnect generator 4-pin (3-pin on Canadian Civic and CR-V models) connector. Turn ignition on. Using backprobe set, measure voltage between PCM 25-pin connector "B" terminal No. 20 (Brown/Black wire) and 31-pin connector "C" No. 5 (White/Red wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If about 5 volts exists, go to step 3. If about 5 volts does not exist, go to next step.
2. Turn ignition off and disconnect negative battery cable. Disconnect PCM 31-pin connector "C". Check for continuity between ground and PCM 31-pin harness connector "C" terminal No. 5 (White/Red wire). If continuity exists, repair short in White/Red wire between PCM 31-pin connector "C" and generator connector. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.
3. Turn ignition off and reconnect generator 4-pin (3-pin on Canadian Civic and CR-V models) connector. Start engine and run at 3000 RPM with no loads and transmission in Park or Neutral, until radiator fan comes on. Allow engine to idle. Using backprobe set, measure voltage between PCM 25-pin connector "B" terminals No. 20 (Brown/Black wire) and 31-pin connector "C" terminal No. 5 (White/Red wire). Turn headlights and rear defogger on. If voltage does not decrease when headlights and rear defogger are turned on, go to next step. If voltage decreases when headlights and rear defogger are turned on, generator FR signal is okay.
4. Turn ignition off. Disconnect negative battery cable, PCM 31-pin connector "C" and generator 4-pin (3-pin on Canadian Civic and CR-V models) connector. Connect a fused jumper wire between ground and generator harness connector terminal No. 4 (White/Red wire) on US models or No. 1 (White/Red wire) on Canadian Civic models. (Scheme 83) Using backprobe set, check for continuity between ground and PCM 31-pin connector "C" terminal No. 5 (White/Red wire). If continuity exists, problem is within generator or regulator. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS. If continuity does not exist, repair open in White/Red wire between PCM 31-pin connector "C" and generator.

1. Turn ignition off. Disconnect generator 4-pin connector (3-pin on Canadian Civic models). Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminal No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 17 (White/Red wire on Civic or White/Green wire on Prelude). See «PIN VOLTAGE CHARTS»(ref-3080) article. If about 5 volts exists, go to step 3. If about 5 volts does not exist, go to next step.
2. Turn ignition off and disconnect negative battery cable. Disconnect PCM 31-pin connector "C". Check for continuity between ground and PCM 31-pin harness connector "C" terminal No. 17 (White/Red wire on Civic or White/Green wire on Prelude). If continuity exists, repair short in White/Red wire (Civic) or White/Green wire (Prelude) between PCM 31-pin connector "C" and generator connector. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.
3. Turn ignition off and reconnect generator connector. Start engine and run at 3000 RPM with no loads and transmission in Park or Neutral, until radiator fan comes on. Allow engine to idle. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 17 (White/Red wire on Civic or White/Green wire on Prelude). Turn headlights and rear defogger on. If voltage does not decrease when headlights and rear defogger are turned on, go to next step. If voltage decreases when headlights and rear defogger are turned on, generator FR signal is okay.
4. Turn ignition off and disconnect negative battery cable. Disconnect PCM 31-pin connector "C". Disconnect generator 4-pin (3-pin on Canadian Civic models) connector. Connect a fused jumper wire between ground and generator harness connector terminal No. 4 (White/Red wire) on US models or No. 1 (White/Red wire) on Canadian models. (Scheme 83) Check for continuity between ground and PCM 31-pin harness connector "C" terminal No. 17 (White/Red wire on Civic or White/Green wire on Prelude). If continuity exists, problem is within generator or regulator. See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS. If continuity does not exist, repair open in White/Red wire on Civic or White/Green wire on Prelude between PCM 31-pin connector "C" and generator.

Scheme 83

1. Turn ignition off. Disconnect generator 4-pin connector. Turn ignition on. Using backprobe set, measure voltage between PCM 25-pin connector "B" terminal No. 20 (Brown/Yellow wire) and 31-pin connector "C" No. 5 (White/Red wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If about 5 volts exists, go to step 3. If about 5 volts does not exist, go to next step.
2. Turn ignition off and disconnect PCM 31-pin connector "C". Check for continuity between ground and PCM 31-pin harness connector "C" terminal No. 5 (White/Red wire). If continuity exists, repair short in White/Red wire between PCM 31-pin connector "C" and generator connector. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.
3. Turn ignition off and reconnect generator 4-pin connector. Start engine and run at 3000 RPM with no loads and transmission in Park or Neutral, until radiator fan comes on. Allow engine to idle. Using backprobe set, measure voltage between PCM 25-pin connector "B" terminals No. 20 (Brown/Yellow wire) and 31-pin connector "C" terminal No. 5 (White/Red wire). Turn headlights and A/C on. If voltage does not decrease when headlights and A/C are turned on, go to next step. If voltage decreases when headlights and A/C are turned on, generator FR signal is okay.
4. Turn ignition off. Disconnect generator 4-pin connector. Turn ignition on. Measure voltage between ground and generator harness connector terminal No. 4 (White/Red wire). (Scheme 83) If about 5 volts exist, problem is within generator or regulator. See appropriate GENERATORS & REGULATORS article. If about 5 volts do not exist, repair open in White/Red wire between PCM 31-pin connector "C" and generator.

IDLE AIR CONTROL VALVE

For Idle Air Control (IAC) valve testing see appropriate Diagnostic Trouble Code (DTC) testing in appropriate SELF-DIAGNOSTICS article.

FAST IDLE THERMO VALVE

Note. Fast idle thermo valve is adjusted by manufacturer and should not be disassembled.

CR-V & Prelude

1. Remove intake air duct from throttle body. Ensure engine coolant temperature is less than 86°F (30°C). Start engine and allow to idle. Place finger over lower port in throttle body and check for airflow. If airflow exists, go to next step. If airflow does not exist, replace fast idle thermo valve and retest.
2. Start engine and run at 3000 RPM with no loads and transmission in Park or Neutral, until radiator fan comes on. Allow engine to idle. Verify fast idle thermo valve is completely closed. If valve is leaking, engine idle speed will decrease when lower port in throttle body is covered. If valve is leaking, check engine coolant level and for air in cooling system. If cooling system is okay, replace fast idle thermo valve and retest.

POWER STEERING PRESSURE (PSP) SWITCH CIRCUIT

Note. This signal informs PCM when power steering load is high.

1. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 26 (Green wire) and 25-pin connector "B" terminal No. 20 (Brown/Black wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If voltage is one volt or more, go to next step. If voltage is less than one volt, go to step 4 .
2. Turn ignition off. Disconnect PSP switch 2-pin connector. On Accord and Odyssey, PSP switch is located below and behind engine. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000) . On Civic and CR-V, PSP switch is located at left rear of engine compartment, between brake master cylinder and plenum chamber. Connect a fused jumper wire between two PSP switch harness connector terminals. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 26 (Green wire) and 25-pin connector "B" terminal No. 20 (Brown/Black wire). If voltage is less than one volt, replace PSP switch. If voltage is one volt or more, repair open in Green wire between PSP switch and PCM 32-pin connector "A". If wire is okay, check for open in Black wire between PSP switch and ground connection. Go to next step.
3. On 2.3L Accord, ground connection is located on inside of left strut tower across from master cylinder. On 3.0L Accord, ground connection is located in front center of cowl. On Civic without Continuously Variable Transmission (CVT), ground connection is located on right side of engine, on thermostat housing, under engine coolant temperature switch. On Civic with CVT, ground connection is located at right front of engine between air cleaner box and starter. On CR-V, ground connection is located behind distributor, next to radiator fan switch. On Odyssey, ground connection is located at right front corner of engine compartment, next to windshield washer reservoir. See «WIRING DIAGRAMS»(ref-3123) article. NOTE: DO NOT hold steering wheel in full lock position for more then 5 seconds.
4. Start engine. Turn steering wheel slowly to full lock position. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 26 (Green wire) and 25-pin connector "B" terminal No. 20 (Brown/Black wire). If battery voltage exists, PSP switch signal is okay. If battery voltage does not exist, go to next step.
5. Turn ignition off. Disconnect PSP switch 2-pin connector. On Accord and Odyssey, PSP switch is located below and behind engine. On Civic and CR-V, PSP switch is located at left rear of engine compartment, between brake master cylinder and plenum chamber. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 26 (Green wire) and 25-pin connector "B" terminal No. 20 (Brown/Black wire). If battery voltage exists, replace PSP switch. If battery voltage does not exist, go to next step.
6. Turn ignition off. Disconnect PCM 32-pin connector "A". Check for continuity between ground and PCM 32-pin harness connector "A" terminal No. 26 (Green wire). If continuity exists, repair short in Green wire between PSP switch connector and PCM 32-pin connector "A". See «WIRING DIAGRAMS»(ref-3123) article. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.

1. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 16 (Green wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If voltage is one volt or more, go to next step. If voltage is less than one volt, go to step 4 .
2. Turn ignition off. Disconnect PSP switch 2-pin connector. On Civic and Prelude (SH), PSP switch is located at left rear of engine compartment, between brake master cylinder and plenum chamber. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000) . On Prelude, PSP switch is located below and behind engine. Connect a fused jumper wire between two PSP switch harness connector terminals. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 16 (Green wire). Go to next step.
3. If voltage is one volt or more, repair open in Green wire between PSP switch and PCM 31-pin connector "C". If wire is okay, check for open in Black wire between PSP switch and ground connection. On Civic without Continuously Variable Transmission (CVT), ground connection is located on right side of engine, on thermostat housing, under engine coolant temperature switch. On Civic with CVT, ground connection is located at right front of engine between air cleaner box and starter. On Prelude, ground connection is located on right side of engine, just behind and below distributor cap, under VTEC pressure switch. See «WIRING DIAGRAMS»(ref-3123) article. If voltage is less than one volt, replace PSP switch. NOTE: DO NOT hold steering wheel in full lock position for more then 5 seconds.
4. Start engine. Turn steering wheel slowly to full lock position. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 16 (Green wire). If battery voltage exists, PSP switch signal is okay. If battery voltage does not exist, go to next step.
5. Turn ignition off. Disconnect PSP switch 2-pin connector. On Civic and Prelude (SH), PSP switch is located at left rear of engine compartment, between brake master cylinder and plenum chamber. On Prelude, PSP switch is located below and behind engine. Turn ignition on. Measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 16 (Green wire). If battery voltage exists, replace PSP switch. If battery voltage does not exist, go to next step.
6. Turn ignition off. Disconnect PCM 31-pin connector "C". Check for continuity between ground and PCM 31-pin harness connector "C" terminal No. 16 (Green wire). If continuity exists, repair short in Green wire between PSP switch connector and PCM 31-pin connector "C". See «WIRING DIAGRAMS»(ref-3123) article. If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.

ELECTRICAL POWER STEERING (EPS) CIRCUIT (S2000)

1. Turn ignition on. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 26 (Blue/Black wire) and 25-pin connector "B" terminal No. 20 (Brown/Yellow wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If battery voltage does not exist, go to next step. If battery voltage exists, go to step 3 .
2. Start engine. Turn steering wheel slowly to full lock position. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 26 (Blue/Black wire) and 25-pin connector "B" terminal No. 20 (Brown/Yellow wire). If battery voltage exists momentarily, PSP switch signal is okay. If battery voltage does not exist momentarily, go to step 4 .
3. Turn ignition off. Disconnect EPS control module 14-pin connector. EPS control module is located at right rear of engine compartment, right of battery. See «COMPONENT LOCATIONS»(ref-3110-S39697342442000041800000) . Turn ignition on. Measure voltage between ground and EPS control module 14-pin harness connector terminal No. 13 (Blue/Black wire). If battery voltage exists, substitute a known good EPS control module and recheck. If battery voltage does not exist, repair open in Blue/Black wire between EPS control module and PCM 32-pin connector "A" terminals No. 26.
4. Turn ignition off. Disconnect EPS control module 14-pin connector. EPS control module is located at right rear of engine compartment, right of battery. Turn ignition on. Measure voltage between ground and EPS control module 14-pin harness connector terminal No. 13 (Blue/Black wire). If battery voltage exists, substitute a known good EPS control module and recheck. If battery voltage does not exist, go to next step.
5. Turn ignition off. Disconnect ECM 32-pin connector "A". Check for continuity between ground and ECM 32-pin harness connector "A" terminal No. 26 (Blue/Black wire). If continuity exists, repair short in Blue/Black wire between EPS and ECM 32-pin connector "A". If continuity does not exist, substitute a known-good PCM and recheck. See SUBSTITUTING PCM in «SELF-DIAGNOSTICS - INTRODUCTION»(ref-3103) article. If symptom or indication goes away, replace original PCM.

STARTER SWITCH SIGNAL

Note. This signal informs PCM when engine is cranking.

1. Place transmission in Neutral or Park position (A/T) or depress clutch pedal (M/T). Turn ignition switch to START position. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 24 (Blue/Orange wire on Accord and Odyssey or Blue/White wire on Civic and CR-V) and 25-pin connector "B" terminal No. 20 (Brown/Black wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If battery voltage exists, starter switch signal is okay. If battery voltage does not exist, go to next step.
2. Inspect STARTER SIGNAL (7.5-amp) fuse. See «STARTER SIGNAL FUSE IDENTIFICATION»(ref-3110-S10516806582000060700000) table. If fuse is okay, repair open in circuit between STARTER SIGNAL (7.5-amp) fuse and PCM 32-pin connector "A" terminal No. 24. If fuse is not okay, repair short in circuit between STARTER SIGNAL (7.5-amp) fuse and PCM 32-pin connector "A" terminal No. 24 or PGM-FI connector terminal No. 2. See «WIRING DIAGRAMS»(ref-3123) article.

1. Place transmission in Neutral or Park position (A/T) or depress clutch pedal (M/T). Turn ignition switch to START position. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 9 (Brown/Black wire) and 31-pin connector "C" terminal No. 6 (Blue/Orange on Civic or Blue/Red wire on Prelude). See «PIN VOLTAGE CHARTS»(ref-3080) article. If battery voltage exists, starter switch signal is okay. If battery voltage does not exist, go to next step.
2. Inspect STARTER SIGNAL (7.5-amp) fuse. See «STARTER SIGNAL FUSE IDENTIFICATION»(ref-3110-S10516806582000060700000) table. If fuse is okay, repair open circuit between STARTER SIGNAL (7.5-amp) fuse and 31-pin connector "C" terminal No. 6. If fuse is not okay, repair short in circuit between STARTER SIGNAL (7.5-amp) fuse and PCM 31-pin connector "C" terminal No. 6 or PGM-FI connector terminal No. 2. Replace STARTER SIGNAL (7.5-amp) fuse. See «WIRING DIAGRAMS»(ref-3123) article.

1. Depress clutch pedal. Turn ignition switch to START position. Press START button. Using backprobe set, measure voltage between PCM 32-pin connector "A" terminals No. 24 (Blue/Orange wire) and 25-pin connector "B" terminal No. 20 (Brown/Yellow wire). See «PIN VOLTAGE CHARTS»(ref-3080) article. If battery voltage exists, starter switch signal is okay. If battery voltage does not exist, go to next step.
2. Inspect STARTER SIGNAL (7.5-amp) fuse. See «STARTER SIGNAL FUSE IDENTIFICATION»(ref-3110-S10516806582000060700000) table. If fuse is okay, repair open in circuit between STARTER SIGNAL (7.5-amp) fuse and PCM 32-pin connector "A" terminal No. 24. If fuse is not okay, repair short in circuit between STARTER SIGNAL (7.5-amp) fuse and PCM 32-pin connector "A" terminal No. 24 or PGM-FI connector terminal No. 2. See «WIRING DIAGRAMS»(ref-3123) article.

STARTER SIGNAL FUSE IDENTIFICATION

IGNITION SYSTEM

Note. For ignition system testing, see BASIC DIAGNOSTIC PROCEDURES article.

EXHAUST GAS RECIRCULATION VALVE

For Exhaust Gas Recirculation (EGR) valve testing see appropriate Diagnostic Trouble Code (DTC) testing in appropriate SELF-DIAGNOSTICS article.

Fuel Tank Pressure Sensor

For Exhaust Gas Recirculation (EGR) valve testing, see appropriate Diagnostic Trouble Code (DTC) testing in appropriate SELF-DIAGNOSTICS article.

EVAP Control Canister Vent Shut Valve

For EVAP Control Canister Vent Shut Valve testing see appropriate Diagnostic Trouble Code (DTC) testing in appropriate SELF-DIAGNOSTICS article.

EVAP Purge Control Solenoid

For EVAP Purge Control Solenoid testing, see appropriate Diagnostic Trouble Code (DTC) testing in appropriate SELF-DIAGNOSTICS article.

EVAP Bypass Solenoid Valve

For EVAP Bypass Solenoid Valve testing, see appropriate Diagnostic Trouble Code (DTC) testing in appropriate SELF-DIAGNOSTICS article.

EVAP 2-Way Valve

1. Remove fuel tank filler cap. Disconnect vapor hose from fuel tank side of 2-way valve, located above EVAP canister. Install "T" fitting into hose. Connect vacuum gauge (0-4 in. Hg scale) and hand vacuum pump to "T" fitting. See STEP 1 in illustration. (Scheme 84)- (Scheme 87).
2. Apply vacuum slowly and continuously while observing vacuum gauge. Vacuum should stabilize momentarily at 0.2-0.6 in. Hg. If vacuum is as specified, go to next step. If vacuum stabilizes at less then 0.2 in. Hg or more then 0.6 in. Hg, replace 2-way valve. Retest system.
3. Move vacuum pump hose from vacuum fitting to pressure fitting. Move vacuum gauge hose from vacuum side to pressure side. See STEP 2 in illustration. (Scheme 84)- (Scheme 87). Slowly pressurize vapor line while observing gauge. If pressure momentarily stabilizes at 0.3 in. Hg, valve is okay. If pressure stabilizes at less than 0.3 in. Hg, replace valve and retest.

Scheme 84

Scheme 85

Scheme 86

Scheme 87

POSITIVE CRANKCASE VENTILATION

On Odyssey, remove intake manifold cover and rear ignition coil cover. On all models, inspect crankcase ventilation hoses and connections for leaks and clogging. Start engine. With engine at idle, pinch and release PCV hose. Valve should click. If valve does not click, check for vacuum at PCV valve end of hose. If manifold vacuum exists, replace PCV valve and recheck. If vacuum does not exist, clear blockage in hose.

PULSED SECONDARY AIR INJECTION SYSTEM

For pulsed secondary air injection system testing see appropriate Diagnostic Trouble Code (DTC) testing in appropriate SELF-DIAGNOSTICS article.

Note. Following procedure should be performed if engine vibrates excessively at idle.

1. Check vacuum lines and hoses for damage and proper connection. Repair/replace hoses as necessary. If vacuum lines and hoses are okay, start and warm engine to normal operating temperature (radiator cooling fan comes on). Allow engine to idle. If idle RPM is less than 800 RPM, go to next step. If idle RPM is not less than 800 RPM, adjust idle speed. See «ON-VEHICLE ADJUSTMENTS»(ref-3100) article.
2. Fully depress brake pedal. With transaxle in gear, have an assistant disconnect and reconnect engine mount control solenoid valve 2-pin connector. (Scheme 88) If there is no noticeable change in idle RPM when engine mount control solenoid valve 2-pin connector is disconnected, go to next step. If there is a noticeable change in idle RPM when engine mount control solenoid valve 2-pin connector is disconnected, engine mount control system is operating properly. Reconnect engine mount control solenoid valve 2-pin connector.
3. Place transaxle in Neutral or Park. Disconnect engine mount control solenoid valve 2-pin connector. Measure voltage of Black/Yellow wire between body ground and engine mount control solenoid valve 2-pin connector terminal No. 2. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Black/Yellow wire between engine mount control solenoid valve 2-pin connector and No. 6 (15-amp) fuse in driver's underdash fuse/relay box. See «WIRING DIAGRAMS»(ref-3123) article.
4. Measure voltage across both terminals (Black/Yellow wire and Green/White wire) of engine mount control solenoid valve 2-pin connector. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Green/White wire between engine mount control solenoid valve and PCM connectors. See «WIRING DIAGRAMS»(ref-3123) article. If Green/White wire is okay, substitute known-good PCM and retest. If battery voltage is now present, replace original PCM.
5. Increase engine speed above 1000 RPM and measure voltage across both terminals (Black/Yellow wire and Green/White wire) of engine mount control solenoid valve 2-pin connector. If battery voltage is not present, go to next step. If battery voltage is present, repair short to ground in Green/White wire between engine mount control solenoid valve and PCM connectors. See «WIRING DIAGRAMS»(ref-3123) article. If Green/White wire is okay, substitute known-good PCM and retest.
6. Disconnect upper vacuum hose from engine mount control solenoid valve, and connect vacuum pump/gauge to hose. Apply vacuum to hose for 20 seconds. If engine mount holds vacuum, go to next step. If engine mount does not hold vacuum, repair or replace vacuum hose or engine mount.
7. Release vacuum from engine mount, and then apply vacuum again. If there is a noticeable change in idle RPM smoothness with or without vacuum applied, go to next step. If there is no noticeable change in idle RPM smoothness with or without vacuum applied, replace engine mount.
8. Remove vacuum pump/gauge from vacuum hose. Reconnect upper vacuum hose to engine mount control solenoid valve. Disconnect lower vacuum hose from engine mount control solenoid valve, and connect vacuum pump/gauge to hose. If vacuum is present, replace engine mount control solenoid valve. If vacuum is not present, repair engine mount control system as necessary.

Scheme 88

Note. Following procedure should be performed if engine vibrates excessively at idle.

1. Check vacuum lines and hoses for damage and proper connection. Repair/replace hoses as necessary. If vacuum lines and hoses are okay, start and warm engine to normal operating temperature (radiator cooling fan comes on). Allow engine to idle. If idle RPM is less than 730 RPM, go to next step. If idle RPM is not less than 730 RPM, adjust idle speed. See «ON-VEHICLE ADJUSTMENTS»(ref-3100) article.
2. Fully depress brake pedal. With transaxle in gear, have an assistant disconnect and reconnect engine mount control solenoid valve 2-pin connector. (Scheme 89) If there is no noticeable change in idle RPM when engine mount control solenoid valve 2-pin connector is disconnected, go to next step. If there is a noticeable change in idle RPM when engine mount control solenoid valve 2-pin connector is disconnected, engine mount control system is operating properly. Reconnect engine mount control solenoid valve 2-pin connector.
3. Place transaxle in Neutral or Park. Disconnect engine mount control solenoid valve 2-pin connector. Measure voltage of Black/Yellow wire between body ground and engine mount control solenoid valve 2-pin connector terminal No. 2. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Black/Yellow wire between engine mount control solenoid valve 2-pin connector and No. 6 (15-amp) fuse in driver's underdash fuse/relay box. See «WIRING DIAGRAMS»(ref-3123) article.
4. Measure voltage across both terminals (Black/Yellow wire and Green/White wire) of engine mount control solenoid valve 2-pin connector. If battery voltage is present, go to next step. If battery voltage is not present, repair open in Green/White wire between engine mount control solenoid valve and PCM connectors. See «WIRING DIAGRAMS»(ref-3123) article. If Green/White wire is okay, substitute known-good PCM and retest. If battery voltage is now present, replace original PCM.
5. Increase engine speed above 1000 RPM and measure voltage across both terminals (Black/Yellow wire and Green/White wire) of engine mount control solenoid valve 2-pin connector. If battery voltage is not present, go to next step. If battery voltage is present, repair short to ground in Green/White wire between engine mount control solenoid valve and PCM connectors. See «WIRING DIAGRAMS»(ref-3123) article. If Green/White wire is okay, substitute known-good PCM and retest.
6. Disconnect upper vacuum hose from engine mount control solenoid valve, and connect vacuum pump/gauge to hose. Apply vacuum to hose for 20 seconds. If engine mount holds vacuum, go to next step. If engine mount does not hold vacuum, repair or replace vacuum hose or engine mount.
7. Release vacuum from engine mount, and then apply vacuum again. If there is a noticeable change in idle RPM smoothness with or without vacuum applied, go to next step. If there is no noticeable change in idle RPM smoothness with or without vacuum applied, replace engine mount.
8. Remove vacuum pump/gauge from upper vacuum hose. Connect vacuum pump/gauge to upper port of engine mount control solenoid valve. Observe vacuum gauge reading with engine at idle and at a speed above 1000 RPM. If manifold vacuum is present at idle and decreases when engine speed is above 1000 RPM, engine mount control system is okay at this time. Check engine mount and vacuum hoses, if necessary. If manifold vacuum is not present at idle and does not decrease when engine speed is above 1000 RPM, replace engine mount control solenoid valve.

Scheme 89