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Home >> Acura >> 2009 >> RL >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Anti-Theft Systems >> Keyless Access System >> DTC Troubleshooting >> DTC B1671: Ignition Switch Control Unit (KEY SW) Circuit Open
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DTC B1671: Ignition Switch Control Unit (KEY SW) Circuit Open

  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 B1671 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 keyless access control unit connector A (31P) terminal No. 13 and ignition switch control unit 10P connector terminal No. 3.
    Fig 1: Checking Continuity Between Keyless Access Control Unit Connector A (31P) And Ignition Switch Control Unit 10P Connector
    G06161040Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 10.

    NO  -Repair open in the wire.

  10. With the built-in key inserted, check for continuity between ignition switch control unit 10P connector terminals No. 3 and No. 6.
    Fig 2: Checking Continuity Between Ignition Switch Control Unit 10P Connector Terminals No. 3 And No. 6
    G06161041Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace the keyless access control unit

    NO  -Replace the ignition switch control unit.