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

Signal Performance

DIC Switch Signal

1

1

B3567 01

B3567 59

DIC Select Switch Signal

1

1

1

P3567 59

DIC Switch Low Reference

--

1

--

--

DIC Switch Ground

--

1

--

--

1. Driver Information Center (DIC) Switch Malfunction

Circuit/System Description

The driver information center (DIC) switch is a multiplexed switch. Battery power is provided to the DIC switch via the instrument panel cluster (IPC). The DIC switch signal circuit is pulled up to battery voltage in the IPC. The IPC also provides the DIC with a low reference circuit. The DIC switch input to the IPC is pulled low when a switch is activated. The DIC switch is a momentary contact that connects a series of resistors in a resistor ladder format. The IPC monitors the DIC switch signal circuit to determine the DIC switch inputs. Each switch state - Set/Reset, Trip/Fuel Information, Vehicle Information and Personalization corresponds to a certain resistance value. The IPC determines the switch pressed by the voltage drop across the resistors.

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 Verification

Ignition ON, verify that when the DIC switches are pressed and released the DIC scan tool parameters toggle between Active and Inactive.

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 2 and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance.
  4. Ignition OFF, test for less than 1 ohm between the ground circuit terminal 5 and ground.
  5. If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Ignition ON, verify all of the scan tool DIC Switch parameters are Inactive.
  7. If any are not Inactive, test the signal circuit terminal listed below for a short to ground. If the circuit tests normal, replace the IPC.
    • DIC Switch Signal Terminal 1
    • DIC Select Switch Signal Terminal 3
  8. Ignition ON, install a 3-amp fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the scan tool DIC Switch parameters, except the DIC Fuel Info. parameter, are Active.
  9. If any are not Active, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC.
  10. Ignition ON, install a 3-amp fused jumper wire between the signal circuit terminal 3 and ground. Verify that the scan tool DIC Fuel Info. parameter is Active.
  11. If not Active, test the signal circuit for a short to voltage. If the circuit tests normal, replace the IPC.
  12. If all the circuits test normal, test or replace the DIC switch assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Head Up Display Switch Replacement
    •  Control Module References for IPC replacement, setup, and programming