You must diagnose the diagnostic trouble codes (DTCs) in the order specified in the DTC list. Failure to do so may result in the following conditions:
• | Extended diagnostic time |
• | Incorrect diagnosis |
• | Incorrect parts replacement |
If the BCM, the Passlockâ„¢ sensor, or the PCM have been replaced, perform the learn procedure before following the diagnostic system check.
Refer to the instrument panel section for additional information on the message center dispaly. Vehicles equipped with a content theft deterrent system use the message center in order to provide an indication similar to that of the vehicle theft deterrent system. Carefully follow the steps within the Theft Deterrent Diagnostic System Check.
The numbers below refer to the step numbers on the diagnostic table.
Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
Tests for an open in the passlock sensor signal circuit which may not set a DTC (B2958) under certain conditions.
The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Install a scan tool. Does the scan tool power up? | -- | Go to Step 2 | Go to Scan Tool Does Not Power Up in Data Link Communications |
Does the scan tool communicate with the BCM and the IPC? | -- | Go to Step 3 | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications | |
3 | Select the Body Control Module display DTCs function on the scan tool. Does the scan tool display any DTCs? | -- | Go to Step 5 | Go to Step 4 |
Does the scan tool display OPEN? | -- | Go to Symptoms | ||
Does the scan tool display any DTCs which begin with a "U"? | -- | Go to DTC U1000 and DTC U1255 Class 2 Communication Malfunction in Data Link Communications | Go to Step 6 | |
6 | Does the scan tool display DTC [B2947, B2948, B2957, B2958, B2960, B2973, B3031, or B3033]? | -- | Go to Diagnostic Trouble Code (DTC) List/Type in Body Control System |