For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 |

1. Plug the scan tool into the data link connector (DLC).
2. Turn the ignition switch to ON.
3. Power up the scan tool.

Does the scan tool power up?

--

Go to Step 2

Go to Scan Tool Inoperative in Data Link Communications

2 |

1. With a scan tool, select Body from the System Selection Menu.
2. Select Body Function Controller, and Data.

Does the scan tool communicate with the BCM?

--

Go to Step 3

Go to Step 4

3 |

1. With the scan tool, read the DTCs.
2. If more than 1 DTC is listed, always select the first DTC listed on the scan tool.

Does the scan tool display any CURRENT DTCs?

--

Go to Diagnostic Trouble Code (DTC) List/Type or applicable DTC table

Go to Step 5

4 | Attempt to establish communications with other class 2 systems (i.e. the PCM, the IPC). Does the scan tool communicate with other class 2 systems? | -- | Go to DTC U1064 Loss of Communications with BCM in Data Link Communications | Go to Scan Tool Does Not Communicate with Components in Data Link Communications
5 |

1. Record any history DTCs.
2. Use the scan tool to clear any history DTCs.
3. Cycle the ignition OFF then ON.
4. Use the scan tool to read the current DTCs.

Does the scan tool display any CURRENT DTCs?

--

Go to Diagnostic Trouble Code (DTC) List/Type or applicable DTC table

Go to Step 6

6 | The malfunction may be intermittent. Inspect all related wiring and electrical connectors for proper connections. Refer to Intermittents and Poor Connections Diagnosis and Testing for Electrical Intermittents in Wiring Systems. Is the procedure complete? | -- | Go to Step 1 | --