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DTC B1672: Ignition Switch Control Unit (KNOB SW) Circuit Short

  1. Clear the DTCs with the HDS.
  2. Turn the ignition switch to LOCK (0).
  3. Insert the built-in key into the ignition key switch.
  4. Turn the ignition switch to ON (II), and to LOCK (0) ten times using the built-in 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.

  6. Turn the ignition switch to LOCK (0).
  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
    G06161042Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short to ground in the wire.

    NO  -Go to step 10.

  10. Remove the built-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
    G06161043Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace the ignition switch control unit.

    NO  -Replace the keyless access control unit.