Diagnostic Instructions
DTC Descriptor
DTC B2971: Driver Door Key Switch Circuit
Circuit/System Description
The key cylinder unlock feature will unlock all of the doors when the BCM receives a Key Unlock Switch signal for greater than 1 second and will unlock all of the doors.
Conditions for Running the DTC
Battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
| • | The BCM detects the Key Unlock Switch Signal has a fault. |
| • | The conditions above must be present for more than 60 seconds. |
Action Taken When the DTC Sets
| • | The BCM stores the DTC to memory. |
| • | The door lock actuators will not lock or unlock. |
Conditions for Clearing the DTC
| • | This DTC will change from current to history when the fault is no longer present. |
| • | A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present. |
| • | The technician issues a scan tool CLEAR DTCs command. |
Reference Information
Schematic Reference
Door Lock/Indicator Schematics
Connector End View Reference
Description and Operation
Power Door Locks Description and Operation
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Ignition OFF, insert the key into the drivers door lock cylinder, turn the key clockwise and hold for greater than 1 second and turn the key counterclockwise and hold for greater than 1 second. Observe the scan tool Door Lock Requestor parameters,
the reading should be Door Key Cyl.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the Driver Door Latch Assembly.
- Test for less than 1.0 ohm of resistance between the ground circuit terminal 8 and ground.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Ignition ON, verify the scan tool Drvr Door Unlock Cmd is OFF. If not the specified value, test the signal circuit terminal 9 for a short to ground. If the circuit tests normal, replace the BCM.
- Install a 3-amp fused jumper wire between the signal circuit terminal 9 and ground, verify the scan tool Drvr Door Unlock Cmd is ON.
| ⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
- If all circuits tests normal, replace the Driver Door Latch Assembly.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
