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No DTC - Powertrain Control Module (Pcm - Accord)

NOTE: If symptom is intermittent, check for loose fuse No. 1 BACK UP LIGHTS, METER LIGHTS (10-amp) in underdash fuse/relay box, poor connection at PCM terminal A18 and gauge assembly.
  1. If Malfunction Indicator Light (MIL) never comes on, even for 2 seconds after ignition is turned on, go to next step. If MIL stays on or comes on after 2 seconds, go to step 5).
  2. Turn ignition on. If low oil pressure light is on, go to next step. If low oil pressure light is not on, replace fuse No. 1 and repair short in wire between fuse No. 1 BACK-UP LIGHTS, METER LIGHTS (10-amp) and gauge assembly. See WIRING DIAGRAMS  section.
  3. If oil pressure light is on, try to start engine. If engine starts, go to next step. If engine does not start, turn ignition on. Measure voltage between ground and PCM terminals A10 and A23. See Figure or Figure . If less than one volt exists, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM. If one volt or more exists, repair open in Black wire(s) between PCM and ground (G101), located at left side of intake manifold on.
  4. Turn ignition off. Using jumper wire, connect PCM terminal A18 to ground. Turn ignition on. If MIL illuminates, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM. If MIL does not illuminate, replace MIL bulb or repair open Light Green/Red wire between PCM connector terminal A18.
  5. Connect scan tool or Honda PGM tester to DLC connector. Turn ignition on. Read DTCs (if present). See RETRIEVING CODES  . If DTCs are present, go to DIAGNOSTIC TROUBLE CODE IDENTIFICATION  . After identifying DTC, go to appropriate Diagnostic Trouble Code (DTC) test. If DTCs are not present, go to next step.
  6. Turn ignition off. Connect SCS service connector to service check connector. See RETRIEVING CODES  . Turn ignition on. If DTCs are not present using MIL, go to next step. If DTCs are present using MIL, repair open or short in Light Green wire between PCM terminal C8 and DLC. See Figure . Go to DIAGNOSTIC TROUBLE CODE IDENTIFICATION  . After identifying DTC, go to appropriate Diagnostic Trouble Code (DTC) test.
  7. Attempt to start engine. If engine starts, go to next step. If engine does not start, go to step 10).
  8. Turn ignition off. Turn ignition on. Measure voltage between PCM connector terminals C7 (Red wire) and D11 (Green/Blue wire). See Figure or Figure . If approximately 5 volts exists, go to next step. If approximately 5 volts does not exist, repair short to ground in Red wire between PCM connector terminal C7 and service check connector. See WIRING DIAGRAMS  section.
  9. Turn ignition off. Disconnect PCM connector "A". Refer to Figure . Turn ignition on. If MIL is on, repair short to ground in Light Green/Red wire between PCM terminal A18 and MIL. If MIL is not on, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM.
  10. Inspect fuse No. 33 PCM (15-amp), located in underhood fuse/relay box. If fuse is okay, go to next step. If fuse is open, repair short in White/Green wire between fuse No. 33 and PGM-FI main relay. See WIRING DIAGRAMS  section. Replace fuse.
  11. Inspect No. 2 FUEL PUMP (15-amp) fuse in underdash fuse/relay box. If fuse is okay, go to next step. If fuse is open, repair short in Red/White wire between underdash fuse/relay box and PGM-FI main relay. See WIRING DIAGRAMS  section. Replace fuse.
  12. Turn ignition on. While observing MIL, disconnect 3-pin Manifold Absolute Pressure (MAP) sensor, Throttle Position (TP) sensor, EGR valve lift sensor and Fuel Tank Pressure (FTP) sensor (if equipped), each one at a time. If MIL goes off for a few seconds and then comes back on, go to next step.
  13. Turn ignition off. Disconnect PCM connector "D". Refer to Figure or Figure . Check for continuity between ground and PCM connector terminals D4 and D10. If continuity does not exist, go to next step. If continuity exists, repair short to ground in wire between PCM connector terminal D4 and MAP sensor, or wire between PCM connector terminal D10 and TP sensor, EGR valve lift sensor or FTP sensor (if equipped).
  14. Disconnect injector resistor, EVAP purge control solenoid valve, front (primary) HO2S (sensor 1) and IAC valve connectors. Turn ignition on. Measure voltage between ground and PCM connector terminals A11 and A24. See Figure or Figure . If battery voltage exists, go to next step. If battery voltage does not exist, check for poor connection at PGM-FI main relay or repair open in wire between PCM and PGM-FI main relay (if necessary). See WIRING DIAGRAMS  section.
  15. If battery voltage was present, reconnect all sensor connectors. Reconnect PCM connector. Turn ignition on. Measure voltage between ground and PCM connector terminals A9 and A22. If voltage reading for either terminal is less than one volt, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM. If voltage reading for either terminal is more than one volt, repair open in wire between ground (G101) on left side of intake manifold and PCM terminals A9 and/or A22.
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