Test Description

The number below refers to the step number on the diagnostic table.

2: Lack of communication may be due to a partial malfunction of the serial data circuit or due to a total malfunction of the serial data circuit. The specified procedure will determine the particular condition.

Diagnostic System Check - Theft Deterrent

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	Turn ON the ignition, with the engine OFF. Attempt to establish communication with the remote control door lock receiver (RCDLR), if equipped. Does the scan tool communication with the RCDLR?	Go to Step 3	Go to Scan Tool Does Not Communicate with Component in Data Link Communications
3	Attempt to establish communication with the theft deterrent control module, if equipped. Does the scan tool communicate with the theft deterrent module?	Go to Step 4	Go to Scan Tool Does Not Communicate with Component in Data Link Communications
4	Select the ECM display DTCs function on the scan tool. Does the scan tool display any DTCs?	Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 1.6L	Go to Symptoms - Theft Deterrent