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 lock 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 lock circuit. |
| • | The condition must be present for 100 ms. |
Action Taken When the DTC Sets
| • | Stores a DTC B2588 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, a short to voltage, in the steering column lock 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
| • | 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 in the I/P fuse block 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.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Column/Ignition Lock Schematics Connector End View Reference: Steering Wheel and Column Connector End Views | |||
1 | Did you perform the Steering Wheel and Column Diagnostic System Check? | Go to Step 2 | |
2 | Test the steering column lock and steering column unlock circuits for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 5 | Go to Step 3 |
3 | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 5 | Go to Step 4 |
|
Important: Perform the BCM RPO Reprogram procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System. Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Did you complete the replacement? | Go to Step 5 | -- | |
5 |
Does the DTC reset? | Go to Step 2 | System OK |
