User Manual

600-904
1
ATTENTION: Refer to the appropriate shop manual for your vehicle to obtain speci c service procedures for this part. If you do not have
a service manual or lack the skill to install this part, it is recommended that you seek the services of a quali ed technician. Pay special
attention to all cautions and warnings included in the shop manual. Read and follow all instructions carefully.
DIAGNOSTIC TROUBLE CODES: TRANSFER CASE MOTOR
©2012 Dorman Products, Inc.
No reproductions in whole or in part without prior written approval.
Disclaimer:
Even though every attempt is made to ensure this information is complete and accurate, it is impossible to account for all possible circumstances or situations. Please consult with a quali ed auto technician
before attempting to perform any work you are not quali ed to do. Automobiles can be hazardous to work on; be sure to take all necessary safety precautions. Failure to do so may result in property damage
or personal injury. Certain motor vehicle standards and performance requirements may apply to your motor vehicle (such as Federal Motor Vehicle Safety Standards by the National Highway Tra c Safety
Administration). Be sure that your work is performed in accordance with such standards and that you do not disable any motor vehicle safety feature.
2007–04 Buick Ranier, 2004–02 Oldsmobile Bravada, 2009–05 Saab 9-7X,
2009–03 Trailblazer/Envoy
DTC-C0306: Motor A or B Circuit Failure
Description:
Diagnostic Trouble Code C0306 is set once the Transfer Case Control Module detects an
open, short-to-ground, or low voltage in the Motor Control A or B circuit, or an open or
short-to-ground fault inside of the transfer case motor.
How to access the diagnostic trouble code (DTC):
Once there has been a DTC set, the vehicle will either set a “service soon” light, or the
lights on the 4x4 switch will  ash and/or stay lit. To access the DTCs, you will need to hook
up a vehicle diagnostic scanner utilizing the service port under the driver side portion
of the dash.
When to clear a DTC:
The diagnostic trouble code (DTC) should only be erased once the positive voltage
concern has been corrected.
How to clear a DTC:
1. The Transfer Case Control Module (TCCM) will clear the DTC once the initial problem
has been  xed.
2. A hard DTC will clear once the vehicle has run through one hundred (100) start cycles
and detects no faults.
3. To clear the DTC manually, you will need a vehicle diagnostic scanner (Scan tool). Once
the DTC has been erased, go back into the vehicle system and verify that the DTC has
been erased and that the system is performing properly.