Test Description

WARNING: This page is about a different car, the 2004 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

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

1: This step determines if the scan tool is receiving power through the DLC connector.
2: The malfunction indicator lamp (MIL) should illuminate whenever the ignition is ON and the engine is not running.
3: This step determines if the PCM is transmitting class 2 serial data to the DLC and that the class 2 data circuit is not open or shorted.
4: This step determines if a DTC is current or stored in history.

Diagnostic System Check - Manual Transmission

Step	Action	Value(s)	Yes	No
1	Install a scan tool. IMPORTANT: Check for applicable service bulletins before proceeding with this test. Perform this test only if there is a driveability complaint or if you have been directed to this table from another section in the service information. Do not turn the ignition OFF when performing this diagnostic procedure. Do not clear the DTCs unless instructed by this diagnostic procedure. Turn ON the ignition, with the engine OFF. Does the scan tool turn ON?	-	Go to Step 2	Go to Diagnostic Starting Point - Data Link Communications in Data Link Communications
2	Is the MIL ON?	-	Go to Step 3	Go to DTC P0650 in Engine Controls - 5.7L
3	Attempt to establish communication with the PCM. Does the scan tool communicate with the PCM?	-	Go to Step 4	Go to Diagnostic Starting Point - Data Link Communications in Data Link Communications
4	Use the scan tool Capture Info function in order to save or capture, Store Info, any DTC Information. Are there any DTCs present?	-	Go to Diagnostic Trouble Code (DTC) List/Type	Go to Symptoms - Manual Transmission