Brake Transmission Shift Interlock System
Brake Transmission Shift Interlock System
If the shifter cannot be shifted out of Park or can be shifted out of Park without depressing the brake pedal, follow the diagnostic procedure below.
Diagnostic and Repair Procedure
- Engage parking brake.
- Connect scan tool to vehicle.
- Check for WCM, PCM and TIPM fault codes.
- For all fault codes perform diagnostics, repair and verification procedures.
- Continue to next step if shifter still shows condition, otherwise stop.
- Using scan tool under the WCM module in the data screen check for change in state of the following signals. If no change in state then perform corresponding circuit repairs:
• 1. Gated park switch: Push and release button on shifter knob.
• 2. BTSI feedback: Push and release brake pedal.
• 3. Brake switch: Push and release brake pedal.
- If change in state occurs in previous steps 1, 2, or 3 then using scan tool under the WCM module in the actuation screen, actuate BTSI. (If shifter can now be released then follow the following step 1), (Otherwise step 2):
- Go To
Test Step 1 - BRAKE TRANSMISSION SHIFT INTERLOCK (BTSI) CIRCUIT TEST
• Turn the ignition off.
• Disconnect the BTSI connector on the shifter.
• The graphic shows a typical shifter connector. Refer to the Wiring Information for the appropriate shifter connector.
• Connect a 12-volt test light between the Ground and the (K321) Brake Transmission Shift Interlock Solenoid Unlock circuits.
• Turn the ignition on.
• While observing the test light, push and release the brake pedal.
Does the test light illuminate brightly when the brake pedal is pushed?
Yes
• Replace the shifter in accordance with the Service Information.
• Perform the Final Verification Test listed below.
No
• Trace and repair the open Ground or the Open (K321) Brake Transmission Shift Interlock Solenoid Unlock circuits as necessary.
• Perform the Final Verification Test listed below.
Final Verification Testing