Inspection and Verification
- Verify the customer concern by operating the system in question.
- Visually inspect the following for obvious signs of mechanical and electrical damage.
Visual Inspection Chart
VISUAL INSPECTION CHARTMechanical Electrical - Axle shaft and universal joints
- Driveshaft and universal joints
- Fluid leaks
- Matching tire size
- Battery junction box (BJB) fuse 27 (20A).
- Smart junction box (SJB) fuses:
- 10 (10A)
- 21 (7.5A)
- 27 (15A)
- 28 (10A)
- 4WD control module
- Wiring harness
- 4WD switch
- Gearmotor encoder assembly (part of the 4WD shift motor)
- Circuitry
- Connector(s)
- If an obvious cause for an observed concern is found, correct the cause (if possible) before proceeding to the next step.
- If the concern remains after the inspection, connect the diagnostic tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
- Check that the program card is properly installed.
- Check the connections to the vehicle.
- Check the ignition switch position.
- If the diagnostic tool still does not communicate with the vehicle, see the diagnostic tool manual. See PINPOINT TEST 1: SMART JUNCTION BOX (SJB) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL .
- Carry out the diagnostic tool data link test. If the diagnostic tool responds with:
- CAN or SCP circuit fault; all electronic control units no response/not equipped, See PINPOINT TEST 1: SMART JUNCTION BOX (SJB) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL , .
- No response/not equipped for the 4WD control module, See TRANSFER CASE ELECTRONIC SHIFT PINPOINT TEST 2: NO COMMUNICATION WITH THE 4WD CONTROL MODULE .
- System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs, and carry out self-test diagnostics for the 4WD module.
- If the DTCs retrieved are related to the concern, See DTC INDEX - 4WD to continue diagnostics.
- If no DTCs related to the concern are retrieved, See TRANSFER CASE ELECTRONIC SHIFT PINPOINT TEST 1: ELECTRONIC SHIFT FUNCTIONAL TEST .