P0930

P0930-BTSI CONTROL CIRCUIT LOW






For a complete wiring diagram, refer to: Electrical Diagrams

Theory of Operation
The brake switch signal must be active before the shift lever can be moved out of the park position. The Shifter lever assembly receives two brake switch signals. The first signal is a CAN C Bus message sent to the shift lever assembly. The second signal is a hardwired brake switch signal to the shift lever assembly. The CAN C Bus message is the primary brake switch signal and the hardwired signal serves as the backup brake switch signal.

When Monitored
Continuously with the ignition on.

Set Condition
The DTC will set if the high side driver detects a short to ground for 10 seconds.

Possible Causes
- ENGINE BRAKE DTC'S PRESENT
- ABS DTC'S PRESENT
- (B29) BRAKE SWITCH SIGNAL SHORT TO GROUND
- SHIFT LEVER ASSEMBLY

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. NAG1 Automatic Transmission

Diagnostic Test
1. ENGINE DTC'S PRESENT
With the scan tool, read Engine DTCs.

Are there any Engine brake DTC's present?
Yes >> Refer to - ENGINE ELECTRICAL DIAGNOSTICS and perform the appropriate diagnostic procedure.
Perform NAG1 TRANSMISSION VERIFICATION TEST - Ver 1. Verification Tests
No >> Go To 2
2. ABS MODULE DTC IS PRESENT
With the scan tool, read ABS Module DTCs.

Are there any ABS DTC's present?
Yes >> Refer to - BRAKES - ABS ELECTRICAL DIAGNOSTICS and perform the appropriate diagnostic procedure.
Perform NAG1 TRANSMISSION VERIFICATION TEST - Ver 1. Verification Tests
No >> Go To 3
3. (B29) BRAKE SWITCH SIGNAL SHORT TO GROUND





Turn the ignition off to the lock position.
Disconnect the Shift Lever Assembly harness connector.

NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance between ground and the (B29) Brake Switch Signal circuit.

Is the resistance below 5.0 ohms?
Yes >> Repair the (B29) Brake Switch Signal for a short to ground.
No >> Go To 4
4. SHIFT LEVER ASSEMBLY
Using the schematics as a guide, inspect the wiring and connectors. Repair as necessary Pay particular attention to all power and ground circuits.
If there are no possible causes remaining, view repair.

Repair
Replace the Shift Lever Assembly per the Service Information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - Ver 1. Verification Tests