GM Service Manual Online
For 1990-2009 cars only

Circuit Description

Important: Do not perform this check if no driveability concern exists.

The Diagnostic System Check - Manual Transmission is an organized approach to identifying a condition created by an electronic engine control system malfunction. The Diagnostic System Check - Manual Transmission is the starting point for any driveability concern diagnosis. This directs the service technician to the next logical step in order to diagnose the concern. Understanding the table and using it correctly will reduce diagnostic time, and will prevent the replacement of good parts.

Test Description

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

  1. This test ensures that the scan tool is getting power.

  2. This test ensures that the scan tool is communicating to the PCM.

  3. This test ensures that the PCM has the latest calibrations.

  4. This test checks to see if any related DTCs should be diagnosed first.

  5. This test checks to see if the customer concern is with Inspection and Maintenance (I/M) testing.

Step

Action

Yes

No

1

Important: 

   • Do NOT perform this test if no driveability condition exists.
   • Search for applicable bulletins before proceeding with the diagnosis.
   • Do not turn OFF the ignition when performing this diagnostic table.
   • Do NOT clear the DTCs unless the diagnostic instructs you to do so.

  1. Connect a scan tool to the data link connector (DLC).
  2. Turn ON the ignition, with the engine OFF.

Does the scan tool power-up?

Go to Step 2

Go to Scan Tool Does Not Power Up in Data Link Communications

2

Does the scan tool display the PCM data?

Go to Step 3

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

3

Does the PCM require a calibration update?

Go to Step 11

Go to Step 4

4

Does the scan tool display any PCM DTCs?

Go to Step 5

Go to Step 8

5

Record the Freeze Frame and Failure Records information with the scan tool.

Did you complete the action?

Go to Step 6

--

6

Were any of the PCM DTCs P0601, P0602, or P1621?

Go to DTC P0601, P0602, P0603, P0604, P0605, P0606, P0607, P1600, P1621, P1627, P1680, P1681, P1683, or P2610 in Engine Controls - 2.2L (L61)

Go to Step 7

7

Was the DTC a P0502?

Go to Diagnostic Trouble Code (DTC) List/Type

Go to Diagnostic System Check - Engine Controls in Engine Controls - 2.2L (L61)

8

Were any BCM DTCs set?

Go to Diagnostic Trouble Code (DTC) List in Body Control System

Go to Step 9

9

Is the customer concern with the Inspection/Maintenance (I/M) testing?

Go to Inspection/Maintenance (I/M) System Check in Engine Controls - 2.2L (L61)

Go to Step 10

10

  1. Using the scan tool, clear the DTCs.
  2. Start the engine. Idle at normal operating temperature.
  3. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Did a DTC set?

Go to Diagnostic Trouble Code (DTC) List/Type

Go to Symptoms - Manual Transmission

11

Update the PCM with the latest calibration as necessary.

Did you perform the task?

Go to Step 12

--

12

  1. Clear all DTCs.
  2. Test drive the vehicle while shifting through all gears.

Does the system operate normally without setting any DTCs?

System OK

Go to Step 1