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No DTC - Powertrain Control Module (Pcm)

NOTE: If symptom is intermittent, check for loose fuse No. 1 BACK UP LIGHTS (10-amp). Fuse is located in underdash fuse/relay box. Also check for poor connection at PCM terminal A18 or an intermittent open in wire between 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 BACK UP LIGHTS (10-amp) and/or repair short in wire between fuse 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 (Black wire) and A23 (Black wire) individually. See 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.
  4. Turn ignition off. Using jumper wire, connect PCM terminal A18 to ground. See Figure . 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 and/or repair open in wire between PCM connector terminal A18 and gauge assembly. See WIRING DIAGRAMS  section.
  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 . See WIRING DIAGRAMS section. 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 terminal terminals C7 (Red wire) and D11 (Green/Blue wire). If approximately 5 volts exists, go to next step. If approximately 5 volts does not exist, repair short to ground in wire between PCM connector terminal C7 and service check connector. See WIRING DIAGRAMS  section.
  9. Turn ignition off. Disconnect PCM connector "A". See Figure . Turn ignition on. If MIL is on, repair short to ground in wire between PCM terminal A18 and MIL. See WIRING DIAGRAMS  section. If MIL is not on, substitute a known-good PCM and recheck. If symptom or indication goes away, replace original PCM.
  10. Inspect ECM/PCM fuse (10-amp). Fuses are located in underhood fuse/relay box. If fuse is okay, go to next step. If fuse is open, repair short in wire between fuse and PGM-FI main relay. See WIRING DIAGRAMS  section. Replace fuse.
  11. Inspect fuse No. 2 FUEL PUMP (15-amp). If fuse is okay, go to next step. If fuse is open, repair short in 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. If MIL does not go off for a few seconds and then come back on, replace sensor that caused MIL to go out.
  13. Turn ignition off. Disconnect PCM connector "D". See Figure . Check for continuity between ground and PCM connector terminals D4 and D10 individually. 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 individually. See 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 connector terminals A11 and A24 and PGM-FI main relay. 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 individually. 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) located left side of intake manifold and PCM terminal(s) terminals A9 and/or A22. See WIRING DIAGRAMS  section.
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