DTC Displaying
WARNING: This page is about a different car, the 2003 GMC Sonoma, 2003 GMC Jimmy, 2003 Chevrolet S10 Pickup, and 2003 Chevrolet Blazer. However, it is still accessible from the selected car via links, so may be relevant.
- 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