B2593

DTC B2593





Circuit Description
The BCM provides the steering column control function, which allows the column to be electronically locked or unlocked. The BCM provides three outputs, steering column lock, steering column unlock, and a steering column lock relay control. The BCM can apply a ground or battery output on the steering column lock or steering column unlock depending on the desired steering column lock motor position. The BCM uses the feedback switch in order to monitor the motor position and determine if the commanded position was accomplished.
The BCM controls the position of the steering column lock motor based on the following input information:
- Ignition position
- Key IN ignition status
- Key OUT of ignition status
- Steering column lock feedback switch
- PASS-Key-system
- PCM password information
- System voltage
The BCM also monitors its circuitry for the steering column unlock circuit. If the BCM detects a malfunction present, a DTC will set.

Conditions for Setting the DTC
- The BCM detects an internal malfunction, an open or a short to voltage, in the steering column unlock circuit.
- The condition must be present for 100 ms.

Action Taken When the DTC Sets
- Stores a DTC B2593 in the BCM memory.
- The PCM may disable fuel if vehicle speed is detected over 2.4 km/h (1.5 mph).
- Sends a message to the IPC to display the SERVICE COLUMN LOCK message.

Conditions for Clearing the DTC
- The BCM no longer detects an internal malfunction, an open or a short to voltage, in the steering column unlock circuit.
- A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present.
- Use a scan tool.

Diagnostic Aids
- The BCM grounds the steering column lock motor through the ignition switch ground. If the BCM is unable to ground steering column lock motor through the ignition switch ground, the BCM will set a DTC B2593.
- Disconnecting the steering column lock connector with the ignition in the ON position will cause the BCM to enter a Fail Enable Standby mode. The steering column will remain inoperative until the Fail Enable Standby mode is cleared. To clear this mode, disconnect the BCM1 & IPC fuse for 15 seconds.
- If the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while moving related wiring and connectors. This can often cause the malfunction to occur.

Test Description
The number below refers to the step number on the diagnostic table.
4. When the BCM is replaced, use a scan tool to perform the BCM RPO Reprogram procedure.