DTC Displaying
- Turn OFF the ignition for 10 seconds.
- Connect PIN 13 on the data link cable (DLC) to a ground. The DLC is located in the cab under the instrument panel on the driver's side.
- Turn ON the ignition, with the engine OFF.
- Observe the transfer case shift control switch select buttons for flashing codes. Refer to Diagnostic Trouble Code (DTC) List .
Important: If the transfer case shift control switch buttons all blink only once and then stop, no fault codes are stored in the transfer case shift control module.
- When one DTC is stored in memory, that code will blink that number of times followed by a 3 second pause and then repeat.
- If more than one code is stored, the first code will blink, followed by a 3 second pause and then the second code will blink.
- This sequence will continue until PIN 13 on the DLC is no longer grounded.
- If the TCCM will not communicate the presence or absence of DTCs, test the above circuits in Self-Test Step 2. If the circuits are complete, then replace the TCCM. Refer to Transfer Case Shift Control Module Replacement .