The transfer case shift-control module normally has battery voltage supplied through the battery positive voltage circuit (CKT 40) at all times. When the ignition is ON, the transfer case shift control module conducts a self-test. This self-test determines if the current memory is the same memory that was retained when the ignition was last turned OFF. This self-test indicates whether the RAM standby power-supply to the transfer case shift control module pin C6 was interrupted. If the power is interrupted, the DTCs would be cleared from memory. If the self-test fails, the transfer case shift-control module sets DTC 1.
This DTC will clear when the voltage supply failure has been corrected and the ignition switch has been cycled 5 times.
The numbers below refer to the step numbers on the diagnostic table.
This step inspects the CTSY LP fuse for an open.
This step test the battery positive voltage circuit, CKT 40, for an open or high resistance.
This step rechecks the CTSY LP fuse for an open.
This step tests the battery positive voltage circuit, CKT 40, for a short to ground.
Step | Action | Yes | No | ||||
---|---|---|---|---|---|---|---|
Schematic Reference: Transfer Case Control Schematics | |||||||
1 |
Important: Check the transfer case shift control module
for DTCs. The transfer case shift control module is not a class 2 device. DTCs are
displayed on the transfer case shift control switch. Use the following four steps
to obtain DTCs.
Did you perform the Diagnostic System Check-Transfer Case? | Go to Step 2 | |||||
Important: This code can get set falsely due to the improper clearing of DTCs or replacement of a blown CTSY LP fuse. Inspect the CTSY LP fuse for an open. Was there a problem found? | Go to Step 4 | Go to Step 3 | |||||
Has DTC 001 cleared? | Go to Step 7 | Go to Step 6 | |||||
Did the fuse blow again? | Go to Step 5 | Go to Step 7 | |||||
Test the battery positive voltage circuit, CKT 40, for a short to ground. Refer to Circuit Testing , and to Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 7 | Go to Step 6 | |||||
6 | Replace the transfer case shift control module. Refer to Transfer Case Shift Control Module Replacement . Did you complete the replacement? | Go to Step 7 | -- | ||||
7 |
Does the DTC reset? | Go to Step 2 | System OK |