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

DTC Descriptor

DTC B0946 01: Suspension Control Selection Indicator Circuit Short to Battery

DTC B0946 06: Suspension Control Selection Indicator Circuit Open Circuit/Short to Ground

Circuit/System Description

The suspension control indicator (LED) is located in the suspension control selection switch (mode switch). The suspension control selection switch allows the driver to change the state of the suspension from performance/luxury (LED OFF) to track/performance (LED ON).

Conditions for Running the DTC

Ignition ON.

Conditions for Setting the DTC

    • The electronic suspension control module has detected that the suspension control indicator LED circuit is shorted to voltage for longer than 60 seconds.
    • The electronic suspension control module has detected that the suspension control indicator LED circuit is shorted to ground or has an open circuit for longer than 60 seconds.

Action Taken When the DTC Sets

    • The ESC will enter the speed dependent damping mode.
    • Both left and right normal force outputs will be set to the default output states.
    •  The ESC module illuminates the LED in the ESC switch.

Conditions for Clearing the DTC

    • A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • Using a Tech2 Scan tool

Reference Information

Schematic Reference

Electronic Suspension Control Schematics .

ESC Malfunction Indicator Lamp

When all DTC's are cleared, and the Diagnostic System Check - Vehicle has been performed the ESC malfunction indicator lamp may stay illuminated for a period of up to 5 seconds when the ignition switch is moved to the "off" position. The ESC malfunction indicator lamp should switch off when the ignition is switched to the "on" position.

Connector End View Reference

Component Connector End Views .

Electrical Information Reference

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

Scan Tool Reference

Control Module References .

Circuit/System Verification

  1. Verify that no other DTCs are present, if any other DTCs are present diagnose those DTCs prior to any circuit or component testing.
  2. Ignition ON, observe the scan tool, activate the suspension control switch, the scan tool should change state from ON to OFF as the switch is toggled.

Circuit/System Testing

  1. Ignition OFF, disconnect the suspension control selection switch . Ignition ON, Test for 4.8-5.2 volts between the 5 volt reference circuit and a known ground.
  2. If less than the specified range, test the 5 volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the electronic suspension control unit.
    If greater than the specified range, test the 5 volt reference circuit for a short to voltage. If the circuit tests normal, replace the electronic suspension control unit.
    Connect the suspension control selection switch harness.
  3. Ignition OFF, test for less than 1.0 ohm of resistance between the earth circuit of the suspension control selection switch and a known ground.
  4. If greater than the specified range, test the earth circuit of the suspension control selection switch for an open/high resistance. If the circuit tests normal, replace the suspension control selection switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    • Position Sensor Replacement.
    •  Electronic Suspension Control Module Replacement setup and programming.