For 1990-2009 cars

### 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 C0000 71: Vehicle Speed Information Circuit Invalid Data

### Circuit/System Description

The wheel speeds are detected by active wheel speed sensors. Each wheel speed sensor receives a 12 V reference voltage from the electronic brake control module (EBCM) and provides an alternating current square wave signal to the EBCM. As the wheel spins, the EBCM uses the frequency of the square wave signal to calculate the wheel speed. The EBCM sends the wheel speed information as a high speed controller area network (CAN) serial data message. Modules connected to the high speed CAN circuit monitor for the vehicle speed information.

### Conditions for Running the DTC

System voltage is between 9 and 16 V

### Conditions for Setting the DTC

A supervised periodic message that includes the wheel speed serial data has not been received.

### Action Taken When the DTC Sets

The electronic suspension control is disabled for the duration of the ignition cycle.

### Conditions for Clearing the DTC

A current DTC clears when the diagnostic runs and passes.

### Reference Information

#### Schematic Reference

Electronic Suspension Control Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Electronic Suspension Control 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, observe the scan tool EBCM Wheel Speed Sensor parameters. The reading should be the same speed on all sensors when driving in a straight line at a speed greater than 20 km/h (13 MPH).

### Circuit/System Testing

1. Ignition ON, verify that DTC C0035, C0040, C0045, or C0050 is not present in the EBCM.

⇒ | If any listed DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle to diagnose that DTC prior to this diagnostic.

2. Replace the K19 Electronic Suspension Control (ESC) Module and verify the DTC does not reset.

⇒ | If the DTC resets, replace the K17 Electronic Brake Control Module (EBCM).

### Repair Instructions

• | Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Control Module References for control module replacement, setup and programming