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Home >> Acura >> 2007 >> RL >> Repair and Diagnosis >> Body & Frame >> Door Locks >> Keyless Access System >> DTC Troubleshooting >> DTC B1672: Ignition Switch Control Unit (KNOB SW) Circuit Short
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DTC B1672: Ignition Switch Control Unit (KNOB SW) Circuit Short

  1. Clear the DTCs with the HDS.
  2. Turn the build-in switch OFF.
  3. Insert the build-in key into the ignition key switch.
  4. Turn the ignition switch ON (II) and OFF ten times using the ignition key.
  5. Check for DTCs with the HDS.

    Is DTC B1672 indicated? 

    YES  - Go to step 6.

    NO  - Intermittent failure, the system is OK at this time. Check for loose or poor connections at the keyless access control unit and at the ignition switch control unit.

  6. Turn the ignition switch OFF.
  7. Disconnect keyless access control unit connector A (31P).
  8. Disconnect the ignition switch control unit 10P connector.
  9. Check for continuity between ignition switch control unit 10P connector terminal No. 7 and body ground.
    Fig 1: Checking Continuity Between Ignition Switch Control Unit 10P Connector Terminal No. 7 And Body Ground
    G05497405Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair a short in the wire.

    NO  - Go to step 10.

  10. Remove the build-in key from the ignition switch.
  11. Check for continuity between ignition switch control unit 10P connector terminals No. 7 and No. 6.
    Fig 2: Checking Continuity Between Ignition Switch Control Unit 10P Connector Terminals No. 7 And No. 6
    G05497406Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Replace the ignition switch control unit.

    NO  - Replace the keyless access control unit.