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PSP Switch Signal Circuit Troubleshooting

  1. Turn the ignition switch ON (II).
  2. Measure voltage between PCM connector terminals A26 and B20.
    Fig 1: Measuring Voltage Between PCM Connector Terminals A26 & B20
    G01464142Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there less than 1.0 V? 

    1. YES  -Go to step 3.
    2. NO  -Go to step  6.
  3. Start the engine.
  4. Turn the steering wheel to the full lock position.
  5. Measure voltage between PCM connector terminals A26 and B20.
    Fig 2: Measuring Voltage Between PCM Connector Terminals A26 & B20
    G01464143Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  -The PSP switch signal is OK.
    2. NO  -Go to step  11.
  6. Turn the ignition switch OFF.
  7. Disconnect the PSP switch 2P connector.
  8. Turn the ignition switch ON (II).
  9. At the harness side, connect PSP switch 2P connector terminals No. 1 and No. 2 with a jumper wire.
    Fig 3: Connecting PSP Switch 2P Connector Terminals No. 1 & No. 2 With A Jumper Wire
    G01464144Courtesy of AMERICAN HONDA MOTOR CO., INC.
  10. Measure voltage between PCM connector terminals A26 and B20.
    Fig 4: Measuring Voltage Between PCM Connector Terminals A26 & B20
    G01464145Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there less than 1.0 V? 

    1. YES  -Replace the PSP switch.
    2. NO  -Check for an open in the wire between the PCM (A26) and the PSP switch or, an open in wire between the PSP switch and G201.
  11. Turn the ignition switch OFF.
  12. Disconnect the PSP switch 2P connector.
  13. Turn the ignition switch ON (II).
  14. Measure voltage between PCM connector terminals A26 and B20.
    Fig 5: Measuring Voltage Between PCM Connector Terminals A26 & B20
    G01464146Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    1. YES  -Replace the PSP switch.
    2. NO  -Go to step 15.
  15. Turn the ignition switch OFF.
  16. Disconnect the PCM connector A (32P).
  17. Check for continuity between body ground and PCM connector terminal A26.
    Fig 6: Checking For Continuity Between Body Ground & PCM Connector Terminal A26
    G01464147Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    1. YES  -Repair short in the wire between the PCM (A26) and the PSP switch.
    2. NO  -Substitute a known-good PCM and recheck (see HOW TO SUBSTITUTE THE PCM FOR TESTING ). If voltage is normal, replace the original PCM.
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