LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Acura >> 2008 >> TL Base >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Idle Control System >> PSP Switch Signal Circuit Troubleshooting
April 5, 2026: LEMON Manuals is launched! Read the announcement.

PSP Switch Signal Circuit Troubleshooting

  1. Start the engine, and let it idle.
  2. Align the steering wheel straight ahead.
  3. Check the PSP SWITCH in the DATA LIST with the HDS.

    Does it indicate ON? 

    YES  -Go to step 4.

    NO  -Go to step  14.

  4. Turn the steering wheel to the full lock position.
  5. Check the PSP SWITCH in the DATA LIST with the HDS.

    Does it change to OFF? 

    YES  -The PSP switch signal circuit is OK.

    NO  -Go to step 6.

  6. Turn the ignition switch OFF.
  7. Disconnect the PSP switch 2P connector.
  8. Start the engine.
  9. Check the PSP SWITCH in the DATA LIST with the HDS.

    Does it change to OFF? 

    YES  -Replace the PSP switch (see POWER STEERING HOSE, LINE, AND PRESSURE SWITCH REPLACEMENT ).

    NO  -Go to step 10.

  10. Turn the ignition switch OFF.
  11. Jump the SCS line with the HDS.
  12. Disconnect ECM/PCM connector E (31P).
  13. Check for continuity between PSP switch 2P connector terminal No. 1 and body ground.
    Fig 1: Checking Continuity Between PSP Switch 2P Connector Terminal No. 1 And Body Ground
    G05458230Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the ECM/PCM (E17) and the PSP switch.

    NO  -Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the symptom/ indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).

  14. Turn the ignition switch OFF.
  15. Disconnect the PSP switch 2P connector.
  16. Connect PSP switch 2P connector terminals No. 1 and No. 2 with a jumper wire, then start the engine.
    Fig 2: Connecting PSP Switch 2P Connector Terminals No. 1 And No. 2 With Jumper Wire
    G05458231Courtesy of AMERICAN HONDA MOTOR CO., INC.
  17. Check the PSP SWITCH in the DATA LIST with the HDS.

    Does it change to ON? 

    YES  -Replace the PSP switch (see POWER STEERING HOSE, LINE, AND PRESSURE SWITCH REPLACEMENT ).

    NO  -Go to step 18.

  18. Turn the ignition switch OFF.
  19. Remove the jumper wire from the PSP switch 2P connector.
  20. Jump the SCS line with the HDS.
  21. Disconnect ECM/PCM connector E (31P).
  22. Connect PSP switch 2P connector terminal No. 1 to body ground with a jumper wire.
    Fig 3: Connecting PSP Switch 2P Connector Terminal No. 1 To Body Ground With Jumper Wire
    G05458232Courtesy of AMERICAN HONDA MOTOR CO., INC.
  23. Check for continuity between body ground and ECM/PCM connector terminal E17.
    Fig 4: Checking Continuity Between Body Ground And ECM/PCM Connector Terminal E17
    G05458233Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 24.

    NO  -Repair open in the wire between the PSP switch and the ECM/PCM (E17).

  24. Check for continuity between PSP switch 2P connector terminal No. 2 and body ground.
    Fig 5: Checking Continuity Between PSP Switch 2P Connector Terminal No. 2 And Body Ground
    G05458234Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the symptom/ indication goes away with a known-good ECM/PCM, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).

    NO  -Repair open in the wire between the PSP switch and G302.