P0928-BTSI CONTROL CIRCUIT
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For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
When the Cluster detects that the brake pedal is pressed by the driver, the Cluster delivers 12 volts to the Brake Transmission Shift Interlock Solenoid (BTSI) on the K321 circuit. The driver is then able to shift out of park. When the brake pedal is released, the voltage on the K321 circuit drops to 0 volts.
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When Monitored:
With the ignition on.
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Set Condition:
The Cluster detects a fault on the (K321) BTSI Unlock Signal circuit.
Possible Causes |
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| (K321) BTSI UNLOCK SIGNAL CIRCUIT SHORTED TO VOLTAGE |
| (K321) BTSI UNLOCK SIGNAL CIRCUIT SHORTED TO GROUND |
| (K321) BTSI UNLOCK SIGNAL CIRCUIT OPEN |
| BTSI SOLENOID GROUND CIRCUIT OPEN |
| SHIFT LEVER ASSEMBLY |
| CLUSTER |
| 1. | Turn the ignition on. |
| 2. | With the scan tool, read DTCs. |
Is the DTC active?
Yes
- Go To 2
No
- The condition that caused this code to set is not present at this time. Check for an intermittent condition by inspecting the related wiring harness for chaffed, pierced, pinched, and partially broken wires. Also inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.
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| 1. | Turn the ignition off. |
| 2. | Disconnect the Shift Lever Assembly harness connector. |
| 3. | Turn the ignition on. |
| 4. | Press the brake pedal. |
| 5. | Using a 12-volt test light connected to ground, measure the voltage of the (K321) BTSI Unlock Signal circuit. |
Does the test light illuminate brightly when the brake pedal is depressed?
Yes
- Go To 3
No
-
Go To 4
3. BTSI SOLENOID GROUND CIRCUITS
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| 1. | Turn the ignition off. |
| 2. | Using a test light connected to B+. Measure the resistance between ground and the Ground circuit in the Shift Lever Assembly harness connector. |
Does the test light illuminate brightly for each circuit?
Yes
- Replace the Shift Lever Assembly in accordance with the Service Information.
- Perform the BODY VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure).
No
- Repair the appropriate ground circuit for an open.
-
Perform the BODY VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM)
- Standard Procedure).
4. (K321) BTSI UNLOCK SIGNAL CIRCUIT SHORTED TO VOLTAGE
 |
| 1. | Turn the ignition off. |
| 2. | Disconnect the Cluster C3 harness connector. |
| 3. | Turn the ignition on. |
| 4. | Using a 12-volt test light connected to ground, measure the voltage of the (K321) BTSI Unlock Signal circuit. |
Does the test light illuminate brightly?
Yes
- Repair the (K321) BTSI Unlock Signal circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure).
No
-
Go To 5
5. (K321) BTSI UNLOCK SIGNAL SHORTED TO GROUND
 |
| 1. | Turn the ignition off. |
| 2. | Using a test light connected to B+, measure the resistance between ground and the (K321) BTSI Unlock Signal circuit. |
Does the test light illuminate brightly?
Yes
- Repair the (K321) BTSI Unlock Signal circuit for a short to ground.
- Perform the BODY VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure).
No
-
Go To 6
6. (K321) BTSI UNLOCK SIGNAL CIRCUIT OPEN
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| 1. | Measure the resistance of the (K321) BTSI Unlock Signal circuit. |
Is the resistance above 10K Ohms?
Yes
- Repair the (K321) BTSI Unlock Signal for an open.
- Perform the BODY VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure).
No
- Replace the Cluster in accordance with the Service Information.
-
Perform the BODY VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM)
- Standard Procedure).