U1009

U1009-00-LIN 2 BUS





For a complete wiring diagram, refer to the Wiring Information.

Theory of Operation

The Body Control Module (BCM) is the Local Interconnect Network (LIN) master for the modules and components on the LIN 2 circuit. The BCM monitors the LIN circuit for any concerns.

- When Monitored:
Continuously with the ignition on.

- Set Condition:
When the BCM detects that the LIN Bus is shorted to ground or battery voltage.





1. CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, clear the DTCs.
3. Cycle the ignition off and on.
4. Wait 10 seconds.
5. With the scan tool, read DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 2

No

- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK FOR AN ACTIVE DTC WITH ONE OF THE COMPONENTS ON THE CIRCUIT DISCONNECTED
1. Turn the ignition off.
2. Disconnect the Inside Rearview Mirror harness connector.
3. Turn the ignition on.
4. Wait 10 seconds.
5. With the scan tool, read DTCs.

Does the scan tool display this DTC as active?

Yes

- Repeat this step, as equipped, for the Compass Module, Light Rain Sensing Module (LRSM), and Humidity Sensor. If all components are disconnected and the DTC is still active, Go To 3

No

- Replace the component that when disconnected allowed the DTC to go to stored.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. CHECK THE (D402) BCM LIN 2 BUS CIRCUIT FOR A SHORT TO VOLTAGE




1. Turn the ignition off.
2. Disconnect the BCM G harness connector.
3. Turn the ignition on.
4. Measure the voltage between ground and the (D402) BCM LIN 2 Bus circuit.

Is there any voltage present?

Yes

- Repair the short to voltage on the (D402) BCM LIN 2 Bus circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 4

4. CHECK THE (D402) BCM LIN 2 BUS CIRCUIT FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Measure the resistance between ground and the (D402) BCM LIN 2 Bus circuit.

Is the resistance above 10k Ohms?

Yes

- Replace the Body Control Module. Body Control Module - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Repair the short to ground in the (D402) BCM LIN 2 Bus circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.