Test D: The Vehicle Does Not Shift Between 4WD Auto and 4H Correctly

Pinpoint Test D: The Vehicle Does Not Shift Between 4WD Auto and 4H Correctly

Test D1-D8:

Test D9-D16:

Test D17-D19:

Test D20-D21:

Test D22:

Normal Operation
With the key in the ON position, the 4WD module (PCM) receives the operator's choice of 4-wheel drive selection from the mode select. The 4WD module (PCM) then controls the electric clutch and shift motor. If the transfer case is not responding to the operator's intentions, systematically check all inputs and outputs to the 4WD module (PCM).

Possible Causes
^ 4WD indicators
^ Transfer case
^ 4WD module (PCM)
^ Circuits: - 359 (GY/RD) _ 779 (BR) - 780 (DB)
^ Transfer case clutch
^ Ignition switch and/or circuitry
^ CAN communication network
^ Instrument cluster (IC)