GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The dash integration module (DIM) has an internal voltage sensor with a dedicated circuit that checks the battery positive voltage and battery negative circuit voltage to determine if it is below 15.5 volts.

Conditions for Running the DTC

This DTC shall run only if the DIM has power, ground and the ignition is not in START mode. This DTC shall execute regardless of the battery voltage, except when the DTC B1390 is set current.

Conditions for Setting the DTC

This DTC shall be set as current when the voltage raises above 16.5 volts for 1200 milliseconds.

Action Taken When the DTC Sets

A message shall be sent out on the class 2 lines to notify the SIR of high battery voltage.

Conditions for Clearing the MIL/DTC

In order to clear the DTC from a current status the voltage shall be less than 15.5 volts for 1200 milliseconds.

Test Description

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

  1. Compares battery voltage with the voltage that the DIM calculates.

Step

Action

Value(s)

Yes

No

Schematic Reference: Starting and Charging Schematics

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. Increase engine speed to above 1,500 RPM.
  4. With a scan tool, observe the Battery Voltage parameter in the DIM data list.

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

15.5 V

Go to Step 4

Go to Step 3

3

  1. Measure the voltage across the battery terminals.
  2. Compare the battery voltage with the Battery Voltage parameter in the DIM data list.

Are the voltages within the specified value?

1.0 Volts

Go to Charging System Test

Go to Step 4

4

Inspect for poor connections at the harness connector of the DIM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 6

Go to Step 5

5

Important: Perform the setup procedure for the DIM.

Replace the DIM. Refer to Dash Integration Module Replacement .

Did you complete the replacement?

--

Go to Step 6

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6

  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