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HOMESERVICE MANUALSHONDA2002CIVIC SIREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 137 (ELECTRONIC THROTTLE CONTROL SYSTEM)DTC TROUBLESHOOTINGDTC P1658: ELECTRONIC THROTTLE CONTROL SYSTEM (ETCS) CONTROL RELAY ON MALFUNCTION
2002 Honda Civic Si

DTC P1658: Electronic Throttle Control System (ETCS) Control Relay ON Malfunction

2002 Honda Civic SiSECTION DTC P1658: Electronic Throttle Control System (ETCS) Control Relay ON Malfunction
WARNING: This page is about a different car, the 2006 Honda Odyssey and 2005 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn the ignition switch ON (II).
  2. Do the ETCS TEST in the INSPECTION MENU with the HDS.

    Is the RELAY circuit OK? 

    1. YES  - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the electronic throttle control system (ETCS) control relay and the PCM.
    2. NO  - Go to step  3.
  3. Turn the ignition switch OFF.
  4. Remove the electronic throttle control system (ETCS) control relay (A) from the passenger's under-dash fuse/relay box.
    Fig 1: Removing ETCS Control Relay
    G03704403Courtesy of AMERICAN HONDA MOTOR CO., INC.
  5. Test the electronic throttle control system (ETCS) control relay (see POWER RELAY TEST ).

    Is the electronic throttle control system (ETCS) control relay OK? 

    1. YES  - Go to step  6.
    2. NO  - Replace the electronic throttle control system (ETCS) control relay, then go to step  13.
  6. Jump the SCS line with the HDS.
  7. Disconnect PCM connector A (44P).
  8. Check for continuity between PCM connector terminal A20 and body ground.
    Fig 2: Checking Continuity Between PCM Connector Terminal A20 And Body Ground
    G03704404Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  - Repair short in the wire between the PCM (A20) and the electronic throttle control system (ETCS) control relay, then go to step  13.
    2. NO  - Go to step  9.
  9. Disconnect PCM connector C (44P).
  10. Turn the ignition switch ON (II).
  11. Measure voltage between PCM connector terminal C4 and body ground.
    Fig 3: Measuring Voltage Between PCM Connector Terminal C4 And Body Ground
    G03704405Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  - Repair short to power in the wire between the PCM (C4) and the electronic throttle control system (ETCS) control relay, then go to step  12.
    2. NO  - Go to step  18.
  12. Turn the ignition switch OFF.
  13. Reconnect all connectors.
  14. Turn the ignition switch ON (II).
  15. Reset the PCM with the HDS.
  16. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  17. Check for Temporary DTCs or DTCs with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    1. YES  - If DTC P1658 is indicated, check for poor connections or loose terminals at the electronic throttle control system (ETCS) control relay and the PCM, then go to step  19. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
    2. NO  - Troubleshooting is complete.
  18. Update the PCM if it does not have the latest software, or substitute a known-good PCM (see PCM UPDATING AND SUBSTITUTION FOR TESTING ).
  19. Check for Temporary DTCs or DTCs with the HDS.

    Are any Temporary DTCs or DTCs indicated? 

    1. YES  - If DTC P1658 is indicated, check for poor connections or loose terminals at the electronic throttle control system (ETCS) control relay and the PCM, then go to step  19. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
    2. NO  - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see PCM REPLACEMENT ).
RENDER: 1.0x

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