GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Cobalt 🢒 DTC 🢒 DTC P0601, P0602, P0603, P0604, P0605, P0606, P0607, P060E, P1600, P1621, P1627, P1681, P1683, or P2610

Description

This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM). This diagnostic also addresses if the ECM is not programmed.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC P0601 Control Module Read Only Memory (ROM)
    • DTC P0602 Control Module Not Programmed
    • DTC P0603 Control Module Long Term Memory Reset
    • DTC P0604 Control Module Random Access Memory (RAM)
    • DTC P0606 Control Module Internal Performance
    • DTC P1621 Control Module Long Term memory Performance
    • DTC P2610 Control Module Ignition Off Timer Performance

Test Description

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

  1. A DTC P0602 indicates that the ECM is not programmed.

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Is DTC P0602 set?

Go to Step 3

Go to Step 5

3

Program the engine control module (ECM). Refer to Service Programming System (SPS) in Programming and Setup.

Does DTC P0602 reset?

Go to Step 4

Go to Step 6

4
  1. Ensure that all tool connections are secure.
  2. Ensure the programming equipment is operating correctly.
  3. Ensure the correct software/calibration package is used.
  4. Attempt to program the ECM. Refer to Service Programming System (SPS) in Programming and Setup.

Does DTC P0602 reset?

Go to Step 5

Go to Step 6

5

Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 6

--

6
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.

Did the DTC fail this ignition?

Go to Step 2

Go to Step 7

7

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information

System OK