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 Descriptors

DTC C0110 04: Pump Motor Circuit Open Circuit
DTC C0110 61: Pump Motor Circuit Actuator Stuck

### Circuit/System Description

The pump motor is an integral part of the brake pressure modulator valve (BPMV), while the pump motor relay is integral to the electronic brake control module (EBCM). The pump motor relay is not engaged during normal system operation. When Antilock Brake System (ABS) or Engine Traction System (ETS) operation is required the EBCM activates the pump motor relay and battery power is provided to the pump motor.

### Conditions for Running the DTC

#### C0110 04

• | The ignition switch is in the ON position.

• | Initialization is complete.

#### C0110 61

• | The test is initiated once per ignition cycle, when the vehicle speed is greater than 8 km/h (5 mph), and a fault was set on the last ignition cycle.

• | The vehicle speed is greater than 20 km/h (13 mph), and the brake is not applied.

• | The vehicle speed is greater than 40 km/h (26 mph).

### Conditions for Setting the DTC

#### C0110 04

The EBCM detects a low voltage in the pump motor supply circuit when the feedback voltage is less than 6 volts for more than 1.8 seconds, and the pump motor is not activated. The ground circuit is open, and the feedback voltage is greater than 0.93 volt for 1.8 seconds, the pump is not activated.

#### C0110 61

The pump motor continues to rotate briefly after activation creating a feedback voltage. The EBCM sets the code if the measured feedback voltage indicates a binding or stalled pump motor.

### Action Taken When the DTC Sets

• | The EBCM disables the ABS/ETS for the duration of the ignition cycle.

• | The ABS indicator turns ON.

• | The traction system indicator turns ON.

• | An ECE response may occur. Refer to ABS Description and Operation for complete description of ECE 13

### Conditions for Clearing the DTC

• | The condition for the DTC is no longer present.

• | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

• | The ABS indicator will remain on until a vehicle speed of 13 Km/h (8 mph) or greater is achieved, unless the Scan has cleared codes.

### Diagnostic Aids

The pump motor is integral to the BPMV. The pump motor is not serviceable. Inspect the power and ground circuits proper connections.

### Reference Information

#### Schematic Reference

Antilock Brake System Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

ABS 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, command the Pump Motor test with a scan tool. listen/feel the pump motor turn on.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the EBCM.
2. Test for less than 5 ohms between the ground circuit terminal 26 and ground.

⇒ | If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 14 and ground.

⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test or replace the BPMV.

4. Ignition OFF, remove the EBCM from the BPMV.
5. Inspect the EBCM to BPMV connector for conditions such as damage, corrosion, or presence of brake fluid.

⇒ | If connector corrosion or damage is evident, replace BPMV and/or EBCM as necessary.

⇒ | If brake fluid is present, replace both BPMV and EBCM.

6. Connect the EBCM harness connector with the BPMV still separated.
7. Connect a test lamp between the pump motor circuits terminals.
8. Command the Pump Motor Test with a scan tool, the test lamp should illuminate when commanded.

⇒ | If test lamp does not illuminate, replace the EBCM. If the DTC resets, replace the BPMV.

9. If all circuits test normal, replace the BPMV.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Brake Pressure Modulator Valve Replacement

• | Control Module References for EBCM replacement, setup, and programming