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DTC B1127

DTC B1127  : Driver's door lock key cylinder switch malfunction

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
DTC Description DTC
B1127 Driver's door lock key cylinder switch malfunction  

DTC (Door Multiplex Control Unit)

  1. Problem verification 1

    -1. With the driver's door key cylinder switch in the neutral position, check the parameter(s) below with the HDS.

    Signal Current conditions
    Values Unit
    Driver's Door Key Cylinder Switch (LOCK)    
    Driver's Door Key Cylinder Switch (UNLOCK)    

    Is either information indicator ON?

    YES 

    Go to step 4.

    NO 

    Go to step 2.

  2. Problem verification 2

    -1. With the driver's door key cylinder in the lock position, check the parameter(s) below with the HDS.

    Signal Current conditions
    Values Unit
    Driver's Door Key Cylinder Switch (LOCK)    
    Driver's Door Key Cylinder Switch (UNLOCK)    

    Are both information indicators ON?

    YES 

    Go to step 3.

    NO 

    Intermittent failure, the system is OK at this time.

  3. Shorted wire check (DR KEY CYL UNLOCK to DR KEY CYL LOCK line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Disconnect the following connector.

    Driver's door latch 10P connector

    -3. Connect terminals A and B with jumper wires.

    Terminal A Power window master switch 37P connector No. 8
    Terminal B Body ground
    Terminal A Power window master switch 37P connector No. 7
    Terminal B Body ground

    -4. Check the parameter(s) below with the HDS.

    Signal Current conditions
    Values Unit
    Driver's Door Key Cylinder Switch (LOCK)    
    Driver's Door Key Cylinder Switch (UNLOCK)    

    Are both information indicators ON?

    YES 

    Repair a short between the wires.

    NO 

    The DR KEY CYL UNLOCK to DR KEY CYL LOCK wire is OK. Faulty driver's door key cylinder switch; replace the driver's door latch .

  4. Determine possible failure area (driver's door latch, others)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Disconnect the following connector.

    Driver's door latch 10P connector

    -3. Check the parameter(s) below with the HDS.

    Signal Current conditions
    Values Unit
    Driver's Door Key Cylinder Switch (LOCK)    
    Driver's Door Key Cylinder Switch (UNLOCK)    

    Is either information indicator ON?

    YES 

    Go to step 5.

    NO 

    Faulty driver's door key cylinder switch; replace the driver's door latch .

  5. Shorted wire check (DR KEY CYL UNLOCK, DR KEY CYL LOCK lines)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Disconnect the following connector.

    Power window master switch 37P connector

    -3. Check for continuity between test points 1 and 2 individually.

    Test condition Vehicle OFF (LOCK) mode
    Driver's door latch 10P connector: disconnected
    Power window master switch 37P connector: disconnected
    Test point 1 Power window master switch 37P connector No. 8
    Test point 2 Body ground
    Test point 1 Power window master switch 37P connector No. 7
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the wire.

    NO 

    The DR KEY CYL UNLOCK and DR KEY CYL LOCK wires are OK. Replace the power window master switch .