GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The Dash Integration Module (DIM) has a designated circuit for monitoring vehicle system voltage. The DIM sends the system voltage status to the instrument cluster via Class 2 message. When the DIM sets B1390, the system voltage status sent to the instrument cluster will default to 12.9 Volts.

Conditions for Running the DTC

Engine speed is greater than 400 RPM.

Conditions for Setting the DTC

The battery voltage is less than 10.5 volts for 30 seconds.

Conditions for Clearing the DTC

    • The DTC will clear from current status when the voltage is greater than or equal to 10.5 volts for 30 seconds with the engine running.
    • A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • Use the ON-Board clearing DTCs feature.
    • Use a scan tool.

Diagnostic Aids

The following conditions are independent of the DTC, but will occur with the DTC set current.

    • The battery charge indicator is illuminated on the instrument cluster.
    • The BATTERY VOLTS LOW message is displayed on the driver information center (DIC).

Step

Action

Value(s)

Yes

No

1

Did you perform the Starting and Charging Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - Engine Electrical

2

  1. Start the engine.
  2. Allow the battery voltage to stabilize.
  3. With a scan tool observe the battery voltage parameter in the DIM data list.

Does the scan tool indicate that the battery voltage is greater than the specified value?

10.5 V

Go to Step 3

Go to Charging System Test

3

With a scan tool, observe the battery voltage parameter in the Instrument Cluster data list.

Does the scan tool indicate that the battery voltage is greater than the specified value?

10.5 V

Go to Diagnostic Aids

Go to Step 4

4

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

Did you complete the replacement?

--

Go to Step 5

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5

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK