P0928
P0928-BTSI CONTROL CIRCUIT
For a complete wiring diagram REFER to DIAGRAMS/ELECTRICAL .
Theory of Operation
The Brake Transmission Safety Interlock (BTSI) is a safety feature that prohibits movement of the shift lever out of park unless certain conditions are met. The Wireless Ignition Node (WIN) controls the BTSI solenoid. The WIN module will engage the BTSI solenoid when the module detects the depression of the brake pedal thus allowing the transmission shift lever to move from the park position to any other position. Failure of the control circuit may inhibit the movement of the shift lever and cause this DTC to set.
- When Monitored:
When the ignition is in accessory, run or start position.
- Set Condition:
This DTC will set if the WIN module detects a problem with the BTSI solenoid control circuit. The DTC will remain active until the WIN module no longer detects a failure of the BTSI control circuit.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview
Diagnostic Test
1. DETERMINE IF THE DTC IS ACTIVE OR STORED
With the scan tool, read WIN DTCs.
Is the DTC active or stored?
Active
- Go to 2
Stored
- Perform the THEFT AND SECURITY SYSTEMS INTERMITTENT TEST.Symptom Related Diagnostic Procedures
2. CHECK THE (K321) BRAKE TRANSMISSION SHIFT INTERLOCK SOLENOID UNLOCK CIRCUIT FOR A SHORT TO GROUND
Turn the ignition off to the lock position.
Disconnect the Wireless Ignition Node (WIN) module harness connector.
Disconnect the Shifter Lever Assembly harness connector.
Measure the resistance between ground and the (K321) Brake Transmission Shift Interlock Solenoid Unlock circuit.
Is the resistance below 100k ohms?
Yes
- Repair the (K321) Brake Transmission Shift Interlock Solenoid Unlock circuit for a short to ground.
- Perform the THEFT AND SECURITY SYSTEMS VERIFICATION TEST.Theft and Security System Verification Test
No
- Go to 3
3. CHECK THE (K321) BRAKE TRANSMISSION SHIFT INTERLOCK SOLENOID UNLOCK CIRCUIT FOR A SHORT TO VOLTAGE
Ignition on, engine not running
Measure the voltage of the (K321) Brake Transmission Shift Interlock Solenoid Unlock circuit.
Is the voltage above 0.5 volts?
Yes
- Repair the (K321) Brake Transmission Shift Interlock Solenoid Unlock circuit for a short to voltage.
- Perform the THEFT AND SECURITY SYSTEMS VERIFICATION TEST.Theft and Security System Verification Test
No
- Go to 4
4. CHECK THE (K321) BRAKE TRANSMISSION SHIFT INTERLOCK SOLENOID UNLOCK CIRCUIT FOR AN OPEN
Turn the ignition off to the lock position.
Reconnect the WIN module harness connector.
Ignition on, engine not running
NOTE: It may be necessary to erase WCM DTCs to actuate the BTSI solenoid.
With the scan tool under WIN, actuate the BTSI solenoid.
Using a 12-volt test light connected to ground, check the (K321) Brake Transmission Shift Interlock Solenoid Unlock circuit in the Shifter Lever Assembly harness connector.
NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
- Go to 5
No
- Repair the (K321) Brake Transmission Shift Interlock Solenoid Unlock circuit for an open.
- Perform the THEFT AND SECURITY SYSTEMS VERIFICATION TEST.Theft and Security System Verification Test
5. CHECK THE SHIFT LEVER ASSEMBLY BTSI SOLENOID
Turn the ignition off to the lock position.
Replace the Shift Lever Assembly.
Reconnect all previously disconnected connectors.
Use the scan tool and erase WIN DTCs.
Turn the ignition off to the lock position, wait a minimum of 15 seconds, then turn the ignition on.
Wait a minimum of one minute, then read WIN DTCs.
Does the DTC P0928-BTSI CONTROL CIRCUIT reset?
Yes
- Replace and program the WIN module.
NOTE: The WIN module requires a specific programing procedure.
- Perform the THEFT AND SECURITY SYSTEMS VERIFICATION TEST.Theft and Security System Verification Test
No
- Repair is complete.
- Perform the THEFT AND SECURITY SYSTEMS VERIFICATION TEST.Theft and Security System Verification Test