GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0602 46: Control Module Not Programmed Vehicle Configuration Not Programmed

DTC P0606: Control Module Internal Performance

DTC P0606 3C: Control Module Internal Performance Internal Communication Failure

DTC P0606 11: Control Module Internal Performance Above Maximum Threshold

DTC P0606 12: Control Module Internal Performance Below Minimum Threshold

DTC P0606 31: Control Module Internal Performance General Checksum Failure

DTC P0606 33: Control Module Internal Performance Special Memory Failure

DTC P0606 37: Control Module Internal Performance Watchdog/Safety Processor Failure

DTC P0606 5A: Control Module Internal Performance Plausibility Failure

DTC P0606 59: Control Module Internal Performance Circuit/Component Protection Time Out

DTC P0607 39:  Control Module Performance Internal Electronic Failure

DTC P060A : Control Module Monitoring Processor Performance

DTC P060A 07: Control Module Monitoring Processor Performance Voltage Above Threshold

DTC P060B :  Control Module Analog to Digital Performance

DTC P060B 03:  Control Module Analog to Digital Performance Voltage Below Threshold

DTC P060B 07:  Control Module Analog to Digital Performance Voltage Above Threshold

DTC P060B 08:  Control Module Analog to Digital Performance Signal Invalid

DTC P060B 11:  Control Module Analog to Digital Performance Above Maximum Threshold

DTC P061C: Control Module Engine Speed Performance

DTC P062B:  Control Module Fuel Injector Control Performance

DTC P062B 03:  Control Module Fuel Injector Control Performance Voltage Below Threshold

DTC P062B 3B:  Control Module Fuel Injector Control Performance Internal Self Test Failed

DTC P062B 3C:  Control Module Fuel Injector Control Performance Internal Communication Failure

DTC P062F: Control Module Long Term Memory Performance

DTC P062F 36: Control Module Long Term Memory Performance EEPROM Failure

DTC P062F 41: Control Module Long Term Memory Performance Operational Software/Calibration Set Not Programmed

Circuit/System Description

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

Conditions for Running the DTC

P0602, P0606, P0607, P060A, P060B, P061C, and P062F

    • The ignition is ON.
    • The DTCs run continuously once the above condition is met.

P062B

    • The engine is running.
    • The DTC runs continuously once the above condition is met.

Conditions for Setting the DTC

P0602

The ECM detects that programming is incomplete for greater than 1 second.

P0606, P0607, P060A, P060B, and P061C

The ECM detects an internal condition for greater than 1 second.

P062B

The ECM detects an internal fuel injector condition once per camshaft revolution.

P062F

The ECM detects an internal EEPROM failure.

Action Taken When the DTC Sets

    • DTCs P0606, P0606 11, P0606 12, P0606 32, P0606 33, P0606 3C, P060A, P061C, P062B, and P062F are Type A DTCs.
    • DTCs P0606 37, P0606 5A, and P060B are Type B DTCs.
    • DTCs P0602 and P0607 are Type C DTCs.

Conditions for Clearing the DTC

    • DTCs P0606, P0606 11, P0606 12, P0606 32, P0606 33, P0606 3C, P060A, P061C, P062B, and P062F are Type A DTCs.
    • DTCs P0606 37, P0606 5A, and P060B are Type B DTCs.
    • DTCs P0602 and P0607 are Type C DTCs.

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Circuit/System Testing

P0602 or P062F

Program the ECM. If DTC P0602 sets after programming, perform the following steps:

    • Ensure that all tool connections are secure.
    • Ensure the programming equipment is operating correctly.
    • Ensure the correct software and the correct calibration is used.
    • Attempt to program the ECM.
       ⇒If DTC P0602 sets, replace the ECM.

P0606, P0607, P060A, P060B, P061C, or P062B

  1. Observe the Freeze Frame/Failure Records with a scan tool.
  2. Clear the DTCs with a scan tool.
  3. Ignition OFF for 30 seconds.
  4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
  5. If DTCs P0606, P0607, P060A, P060B, P061C, or P062B failed this ignition, replace the ECM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for ECM replacement, setup, and programming

Repair Verification

Ignition ON, observe the scan tool DPF soot mass parameter. The parameter should be less than 24 grams.

If greater than the specified range, perform a DPF service regeneration. Refer to Exhaust Particulate Filter Cleaning.