Diagnostic System Check - Door Systems

DIAGNOSTIC SYSTEM CHECK - DOOR SYSTEMS

TEST DESCRIPTION

Step 1 - 3:

Step 4 - 11:

The numbers below refer to the step numbers on the diagnostic table.
2. Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or a total malfunction of the class 2 serial data circuit, however, lack of communication may also be caused by an unpowered or ungrounded module. The specified procedure will determine the particular condition. Enabling the headlamps in this step verifies that a door module is not using an alternate path to ground through the switch illumination circuit, a condition which could cause the DTC or malfunction to be intermittent.
4. The symptom list in Symptoms will determine the correct diagnostic procedure to use.
5. The presence of DTCs U1161, U1162, U1163 or U1170 indicate one or more of the door modules is not communicating on the power door serial data line.
8. The presence of other DTCs which begin with "U" indicate some other system control module is not communicating. The specified procedure will compile all the available information before tests are performed.