FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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With Column Shift






P0930-BTSI CONTROL CIRCUIT LOW - COLUMN SHIFT

For a complete wiring diagram, refer to the Wiring Information

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 (SLA) Electronic Shift Module (ESM) receives two brake switch signals. The first signal is a CAN C Bus message sent to the shifter lever assembly. The second signal is a hard wired brake switch signal to the shifter lever assembly from the BCM. The CAN C Bus message is the primary brake switch signal and the hard wired signal serves as the backup brake switch signal. These two brake switch signals are compared against each other to verify proper brake switch operation.

- 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.





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

1. ENGINE CONTROL MODULE (ECM) or POWERTRAIN CONTROL MODULE (PCM) DTCS PRESENT
1. With the scan tool, read ECM or PCM DTCs.

Are there any brake DTCs present?

Yes

- Testing and Inspection Perform the appropriate diagnostic procedure.

No

- Go To 2

2. BCM DTCS PRESENT
1. With the scan tool, read BCM DTCs.

Are there any BCM DTCs present?

Yes

- Perform the appropriate diagnostic procedure. Testing and Inspection

No

- Go To 3

3. (K321) BTSI CONTROL CIRCUIT SHORTED TO GROUND




1. Turn the ignition off to the lock position.
2. Disconnect the ESM C1 harness connector.
3. Ignition on, engine not running.
4. With the scan tool under BCM, actuate the BTSI.
5. Using a 12 volt test light connected to ground, check the (K321) BTSI Control circuit.

Does the test light illuminate brightly while cycling on and off on all (K321) BTSI Control circuit?

Yes

- Replace the Electronic Shift Module (ESM).
- Perform the NAG1 TRANSMISSION VERIFICATION TEST. NAG1 Transmission Verification Test.

No

- Go To 4

4. (K321) BTSI CONTROL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off to the lock position.
2. Disconnect the BCM harness connector.
3. Measure the resistance between ground and the (K321) BTSI Control circuit.

Is the resistance below 5.0 Ohms?

Yes

- Repair the (K321) BTSI Control circuit for a short to ground.
- Perform the NAG1 TRANSMISSION VERIFICATION TEST. NAG1 Transmission Verification Test.

No

- Go To 5

5. (K321) BTSI CONTROL CIRCUIT OPEN
1. Turn the ignition off to the lock position.

NOTE: Check connectors - Clean/repair as necessary.

2. Measure the resistance of the (K321) BTSI Control circuit between the Electronic Shift Module (ESM) harness connector and the BCM harness connector.

Is the resistance above 5.0 Ohms?

Yes

- Repair the (K321) BTSI Control circuit for an open.
- Perform the NAG1 TRANSMISSION VERIFICATION TEST. NAG1 Transmission Verification Test.

No

- Go To 6

6. ELECTRONIC SHIFT MODULE (ESM)
1. Using the schematics as a guide, inspect the wiring and connectors. Repair as necessary. Pay particular attention to all power and ground circuits.

Repair

- Replace the Electronic Shift Module (ESM).
- Perform the NAG1 TRANSMISSION VERIFICATION TEST. NAG1 Transmission Verification Test.