The number(s) below refer to the step number(s) 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.
Check for the presents of DTC's.
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.
Check for the presents of DTC's.
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 |
Does the scan tool communicate with each of the Modules? | Go to Step 3 | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications | |
Select the the display DTCs function on the scan tool Does the scan tool display any DTCs which begin with a "U"? | Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications | Go to Step 4 | |
Select the the Powertrain Control module display DTCs function on the scan tool. Does the scan tool display any DTCs for VSS, TP Sensor or System Voltage? | Go to Diagnostic Trouble Code (DTC) List/Type in Engine Controls. | Go to Step 5 | |
Select the the Suspension Control module display DTCs function on the scan tool. Does the scan tool display any DTCs? | Go to Step 6 | Go to Symptoms | |
6 |
Important: Do not turn the ignition OFF after clearing the DTC's. Does the scan tool display any DTCs? | Go to Step 7 | System OK |
7 | Does the scan tool display DTC C0550 or C0551? | Go to Step 8 | |
8 | Does the scan tool display DTC C0870? | Go to DTC C0870 Device Voltage Reference Output # 1 Circuit Malfunction | Go to Step 9 |
9 | Does the scan tool display all of the following DTC's C0575, C0580, C0585 and C0590? | Go to Step 10 | |
10 | Does the scan tool display any of the following DTC's C0575, C0580, C0585 or C0590? | Go to Step 11 | |
11 |
Important: Do not turn the ignition OFF after clearing the DTC's. Does the DTC reset? | Go to Symptoms |