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.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Gages Switch Signal

1

1

1

Trip Switch Signal

1

1

1

Options Switch Signal

1

1

1

Reset Switch Signal

1

1

1

Fuel Switch Signal

1

1

1

DIC Switch Low Reference

--

1

1

1. Driver Information Center (DIC) Switch Malfunction

Circuit/System Description

The driver information center (DIC) switch is a multiplexed switch that also functions as a DIC dimmer switch. Battery power is provided to the DIC switch via the instrument panel cluster (IPC). The IPC also provides the DIC switch with a low reference. The switch input to the IPC is pulled low when a switch is activated. The IPC monitors the DIC switch signal circuits to determine the DIC switch input.

Reference Information

Schematic Reference

Instrument Cluster Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Driver Information Center (DIC) Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the DIC switch assembly.
  2. Ignition OFF, test for less than 1 ohm between the low reference circuit terminal F and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance.
  4. Ignition ON, verify that all scan tool DIC Switch parameters are Inactive, Released or Off.
  5. If any are not Inactive, Released or Off, test the signal circuit terminals listed below for a short to ground. If the circuit tests normal, replace the IPC.
    • Gages switch signal terminal H
    • Trip switch signal terminal J
    • Options switch signal terminal K
    • Reset switch signal terminal G
    • Fuel switch signal terminal C
  6. Ignition ON, install a 3A fused jumper wire between the signal circuit terminals listed below and the low reference circuit terminal F. Verify that all scan tool DIC switch parameters are Active, Depressed or On.
  7. • Gages switch signal terminal H
    • Trip switch signal terminal J
    • Options switch signal terminal K
    • Reset switch signal terminal G
    • Fuel switch signal terminal C
    If any DIC switch parameters are not Active, Depressed or On, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC.
  8. If all circuits test normal, test or replace the DIC switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Driver Information Display Switch Replacement
    •  Control Module References for the IPC replacement, setup and programming