GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The voltage level is monitored by the engine control module (ECM) and is sent as a Class 2 data message to the instrument panel cluster (IPC).

Conditions for Running the DTC

    • The key is in the ON position.
    • The engine is running.
    • Engine speed is greater than 1,500 RPM

Conditions for Setting the DTC

This DTC will be set as current when the voltage is greater than 16.0 volts for 30 seconds with the engine running.

Action Taken When the DTC Sets

The charge indicator and driver warning message will be set in the driver information center (DIC).

Conditions for Clearing the MIL/DTC

The DTC clears as a current status when the voltage falls below 16.2 volts for 30 seconds with the engine running.

Step

Action

Value(s)

Yes

No

1

Did you perform the Engine Electrical Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Engine Electrical

2

  1. Install a scan tool.
  2. Start the engine.
  3. Allow voltage to stabilize.
  4. With a scan tool observe the Volts parameter in the IPC data list using the scan tool.

Does the scan tool indicate that the Volts parameter is within the specified range?

10.5-16.2 V

Go to Step 3

Go to Charging System Test

3

Replace the IPC. Refer to Instrument Cluster Replacement in Instrument Panel, Gages, and Console.

Did you complete the replacement?

--

Go to Step 4

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4

  1. Use the scan tool in order to clear the DTC.
  2. Operate the vehicle within the conditions for running the DTC.

Does the DTC reset?

--

Go to Step 2

System OK