Idle Control System: Diagnosis Honda Odyssey II

DTC Troubleshooting

DTC INDEX

Note. If DTC P1519 is stored at same time as DTC P0505, troubleshoot DTC P1519 first, then recheck for DTC P0505.

Scheme 338

1. Start the engine. Hold the engine at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on.
2. Check the engine speed at idle with no-load conditions: headlights, blower fan, rear window defogger, radiator fan, and air conditioner are not operating. Is the engine running at 730 +/- 50 rpm? YES: Intermittent failure, system is OK at this time. NO: If the idle speed is less than 680 rpm, go to step 3; if it's 780 rpm or higher, go to step 4 .
3. Disconnect the IAC valve 3P connector. Does the engine speed increase or fluctuate? YES: Adjust the idle speed (see «Idle Speed Adjustment»(ref-171138-S15708429122005011300000) ). If the idle speed will not adjust properly, clean the passage in the throttle body, and then adjust it again. NO: Replace the IAC valve.
4. Turn the ignition switch OFF.
5. Remove the intake air duct from the throttle body.
6. Start the engine, and let it idle.
7. Put your fingers on the lower port (A) in the throttle body. Does the engine speed drop? YES: Check the idle speed (see «Idle Speed Adjustment»(ref-171138-S15708429122005011300000) ). If it's out of specification, replace the IAC valve. NO: Check for vacuum leaks with the throttle valve completely closed, and repair as needed.

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Scheme 344

1. Reset the PCM (see «HOW TO RESET THE PCM»(ref-171136-S26798080882005011100000) ).
2. Turn the ignition switch ON (II). Is DTC P1519 indicated? YES: Go to step 3. NO: Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the IAC valve and at the PCM.
3. Turn the ignition switch OFF.
4. Disconnect the IAC valve 3P connector.
5. Turn the ignition switch ON (II).
6. Measure voltage between IAC valve 3P connector terminal No. 2 and body ground. Is there battery voltage? YES: Go to step 7. NO: Repair open in the wire between the IAC valve and the PGM-FI main relay.
7. Turn the ignition switch OFF.
8. Check for continuity between body ground and IAC valve 3P connector terminal No. 1. Is there continuity? YES: Go to step 9. NO: Repair open in the wire between the IAC valve and G101.
9. Disconnect PCM connector B (25P).
10. Check for continuity between body ground and PCM connector terminal B23. Is there continuity? YES: Repair short in the wire between the IAC valve and the PCM (B23). NO: Go to step 11.
11. Connect IAC valve 3P connector terminal No. 3 to body ground with a jumper wire.
12. Check for continuity between PCM connector terminal B23 and body ground. Is there continuity? YES: Go to step 13. NO: Repair open in the wire between the IAC valve and the PCM (B23).
13. Remove the jumper wire from the IAC valve 3P connector, then reconnect the IAC valve 3P connector.
14. Turn the ignition switch ON (II).
15. Measure voltage between body ground and PCM connector terminal B23. Is there battery voltage? YES: Substitute a known-good PCM and recheck (see «HOW TO SUBSTITUTE THE PCM FOR TESTING PURPOSE»(ref-171136-S22224174352005011100000) ). If the symptom/indication goes away, replace the original PCM. NO: Replace the IAC valve.

Scheme 345

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Scheme 350

1. Reset the PCM (see «HOW TO RESET THE PCM»(ref-171136-S26798080882005011100000) ).
2. Turn the ignition switch ON (II). Is DTC P1519 indicated? YES: Go to step 3. NO: Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the IAC valve and at the PCM.
3. Turn the ignition switch OFF.
4. Disconnect the IAC valve 3P connector.
5. Turn the ignition switch ON (II).
6. Measure voltage between IAC valve 3P connector terminal No. 2 and body ground. Is there battery voltage? YES: Go to step 7. NO: Repair open in the wire between the IAC valve and the PGM-FI main relay.
7. Turn the ignition switch OFF.
8. Check for continuity between body ground and IAC valve 3P connector terminal No. 1. Is there continuity? YES: Go to step 9. NO: Repair open in the wire between the IAC valve and G101.
9. Disconnect PCM connector B (24P).
10. Check for continuity between body ground and PCM connector terminal B23. Is there continuity? YES: Repair short in the wire between the IAC valve and the PCM (B23). NO: Go to step 11.
11. Connect IAC valve 3P connector terminal No. 3 to body ground with a jumper wire.
12. Check for continuity between PCM connector terminal B23 and body ground. Is there continuity? YES: Go to step 13. NO: Repair open in the wire between the IAC valve and the PCM (B23).
13. Remove the jumper wire from the IAC valve 3P connector, then reconnect the IAC valve 3P connector.
14. Turn the ignition switch ON (II).
15. Measure voltage between body ground and PCM connector terminal B23. Is there battery voltage? YES: Substitute a known-good PCM and recheck (see «HOW TO SUBSTITUTE THE PCM FOR TESTING PURPOSE»(ref-171136-S22224174352005011100000) ). If the symptom/indication goes away, replace the original PCM. NO: Replace the IAC valve.