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P0838






P0838-FOUR WHEEL DRIVE (4WD) SWITCH CIRCUIT LOW





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

- When Monitored:
With the ignition on.

- Set Condition:
The Cluster detects low voltage on the Transfer Case Position Sensor Input circuit.





1. CHECK FOR AN ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
1. Turn the ignition on.
2. With the scan tool, read the 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. TRANSFER CASE SELECTOR SWITCH
1. Turn the ignition off.
2. Disconnect the Transfer Case Selector Switch harness connector.
3. Turn the ignition on.
4. With the scan tool, read the DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 3

No

- Replace the Transfer Case Selector Switch. .
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. (K77) TRANSFER CASE POSITION SENSOR INPUT CIRCUIT SHORTED TO GROUND
1. Turn the ignition off to the lock position.
2. Disconnect the Cluster C1 harness connector.
3. Measure the resistance between ground and the (K77) Transfer Case Position Sensor Input circuit.

Is the resistance less than 5.0 Ohms?

Yes

- Repair the short to ground in the (K77) Transfer Case Position Sensor Input circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the Cluster. Instrument Cluster - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.