GM Service Manual Online
For 1990-2009 cars only

Circuit Description

Output driver modules (ODMs) are used by the powertrain control module (PCM) to turn ON many of the current-driven devices that are needed to control various engine and transaxle functions. Each ODM is capable of controlling up to 7 separate outputs by applying ground to the device which the PCM is commanding ON. Unlike the quad driver modules (QDMs) used in prior model years, ODMs have the capability of diagnosing each output circuit individually. Diagnostic trouble code (DTC) P0650 set indicates an improper voltage level on the output circuit that controls the malfunction indicator lamp (MIL).

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

    • An improper voltage level has been detected on ODM D output 1, the MIL control circuit.
    • The ignition voltage is between 9-18 volts.
    • The above conditions are present for at least 30 seconds.

Action Taken When the DTC Sets

    • The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
    • The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

    • The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
    • A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
    • A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
    • Clear the MIL and the DTC with a scan tool.

Diagnostic Aids

Check for the following conditions:

    • Poor connection at the PCM--Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.
    • Damaged harness--Inspect the wiring harness for damage. If the harness appears to be OK, disconnect the PCM, turn the ignition ON and observe a DMM connected between the MIL control circuit and ground at the PCM harness connector while moving connectors and wiring harnesses related to the MIL. A change in voltage will indicate the location of the malfunction.

Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

Test Description

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

  1. This vehicle is equipped with a PCM which utilizes an electrically erasable programmable read only memory (EEPROM). When the PCM is replaced, the new PCM must be programmed.

DTC P0650 - MIL Control Circuit

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

1

Did you perform the Diagnostic System Check-Engine Controls?

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Important: If the MIL fuse is open, locate and repair a short to ground in the MIL battery positive voltage circuit or a shorted cluster.

Inspect the fuse that supplies voltage to the MIL.

Was the fuse open?

Go to Step 12

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the PCM. Refer to Powertrain Control Module Replacement .
  3. Important: If the jumper fuse opens, locate and repair a short to voltage in the MIL control circuit or a shorted cluster.

  4. Install a 3-amp fused jumper between the MIL control circuit at the PCM harness connector and a good ground.
  5. Turn ON the ignition, with the engine OFF.

Is the MIL illuminated?

Go to Step 4

Go to Step 5

4

Leaving the ignition ON, remove the jumper.

Is the MIL illuminated?

Go to Step 7

Go to Step 9

5

  1. Remove the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.
  2. Test the MIL control circuit for an open and repair as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 12

Go to Step 6

6

Test the MIL battery positive voltage circuit for an open and repair as necessary.

Did you find and correct the condition?

Go to Step 12

Go to Step 8

7

  1. Remove the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.
  2. Test the MIL control circuit for a short to ground and repair as necessary.

Did you find and repair the condition?

Go to Step 12

Go to Step 10

8

Inspect the cluster harness connector for faulty connections and repair as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find and repair the condition?

Go to Step 12

Go to Step 10

9

Inspect the PCM and the PCM harness connector for faulty connections and repair as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find and correct the connection?

Go to Step 12

Go to Step 11

10

Repair or replace the cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.

Did you complete the repair or replacement?

Go to Step 12

--

11

Replace the PCM. Refer to Powertrain Control Module Replacement .

Did you complete the replacement?

Go to Step 12

--

12

  1. Use the scan tool in order to clear the DTCs.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC run and pass?

Go to Step 13

Go to Step 2

13

With a scan tool, observe the stored information, Capture Info.

Does the scan tool display any DTCs that you have not diagnosed?

Go to Diagnostic Trouble Code (DTC) List

System OK