For 1990-2009 cars

### Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. The lack of communication may be caused by a partial or a total malfunction of the circuit containing the class 2 serial data. The specified procedure will determine the particular condition.

2. The presence of DTCs which begin with a U indicate some other module is not communicating. The specified procedure will collect all the available information before tests are performed.

3. The presence of ABS DTCs indicates the TPM system could be disabled due to a malfunction with the antilock brake system.

Step | Action | 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
2 |

1. Turn ON the ignition, with the engine OFF.
2. Attempt to establish communications with the Electronic Brake Control Module (EBCM).

Does the scan tool communicate with the EBCM?

Go to Step 3

Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

3 | Select the ABS Diagnostic Trouble Codes DTC function on the scan tool. Does the scan tool display any DTCs that begin with a "U"? | Go to Diagnostic Trouble Code (DTC) List in Data Link Communications | Go to Step 4
4 | Does the scan tool display any ABS DTCs? | Go to Diagnostic System Check - ABS in Antilock Brake System | Go to Step 5
5 | Does the scan tool display DTC C1245? | Go to DTC C1245 | Go to Symptoms - Tire Pressure Monitoring