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M/T model

  1. Turn the ignition switch ON (II).
  2. Shift the transmission to 1st gear.
  3. Measure voltage between ECM connector terminals B16 and B20.
    Fig 1: Identifying ECM Connector Terminals B16 And B20
    G03680983Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage ? 

    1. YES  -Go to step 4.
    2. NO  -Go to step  6.
  4. Shift the transmission to neutral position.
  5. Measure voltage between ECM connector terminals B16 and B20.
    Fig 2: Measuring Voltage Between ECM Connector Terminals B16 And B20
    G03680984Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there less than 1.0 V ? 

    1. YES  -The neutral position switch signal is OK.
    2. NO  -Go to step  13.
  6. Turn the ignition switch OFF.
  7. Disconnect the neutral position switch 2P connector.
  8. Turn the ignition switch ON (II).
  9. Measure voltage between ECM connector terminals B16 and B20.
    Fig 3: Identifying ECM Connector Terminals
    G03680985Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage ? 

    1. YES  -Replace the neutral position switch.
    2. NO  -Go to step 10.
  10. Turn the ignition switch OFF, and wait for 10 seconds.
  11. Disconnect ECM connector B (25P).
  12. Check for continuity between ECM connector terminal B16 and body ground.
    Fig 4: Checking Continuity Between ECM Connector Terminal B16 And Body Ground
    G03680986Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity ? 

    1. YES  -Repair short in the wire between the ECM (B16) and the neutral position switch.
    2. NO  -Update the ECM if it does not have the latest software, or substitute a known-good ECM; 2000-2001 M/T models (see HOW TO TROUBLESHOOT CIRCUITS AT THE ECM ), 2002-2006 M/T models (see ECM UPDATING AND SUBSTITUTION FOR TESTING-2002-2006 M/T MODELS AND CVT MODEL ), then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM (see ECM REPLACEMENT ).
  13. Turn the ignition switch OFF.
  14. Disconnect the neutral position switch 2P connector.
  15. At the sensor side, check for continuity between neutral position switch 2P connector terminals No. 1 and No. 2 with the transmission in 1st gear.
    Fig 5: Checking Continuity Between Neutral Position Switch 2P Connector Terminals 1 And 2
    G03680987Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity ? 

    1. YES  -Go to step 16.
    2. NO  -Replace the neutral position switch.
  16. Turn the ignition switch ON (II).
  17. Measure voltage between neutral position switch 2P connector terminal No. 2 and body ground.
    Fig 6: Measuring Voltage Between Neutral Position Switch 2P Connector Terminal 2 And Body Ground
    G03680988Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage ? 

    1. YES  -Repair open in the wire between the neutral position switch and G101.
    2. NO  -Repair open in the wire between the ECM (B16) and the neutral position switch.
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