Operation CHARM: Car repair manuals for everyone.
Home >> Chevrolet >> 2013 >> Silverado 1500 4WD V8-6.0L Hybrid >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> C Code Charts >> C12E8

C12E8




DTC C0110, C12E0, C12E8, or C12E9

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC C0110 00

-
Pump Motor Circuit

DTC C0110 61

-
Pump Motor Circuit Actuator Stuck

DTC C12E0 00

-
ABS Pump Motor Performance

DTC C12E8 00

-
ABS Pump Motor Stuck

DTC C12E9 00

-
ABS Pump Motor Stuck On

Diagnostic Fault Information






Circuit/System Description

The pump motor is a bi-directional motor and is an internal part of the brake pressure modulator valve assembly. There are three solid state relays in the electronic brake control module (EBCM) that operate the pump. The pump motor runs every few brake stops in order to fill the high pressure accumulator with brake fluid anytime the engine is running.

Conditions for Running the DTC

* Ignition ON.

* The system enable relay is ON.

* Ignition voltage is greater than 10 volts.

* The pump motor has been commanded ON, OFF and ON again.

Conditions for Setting the DTC

* The EBCM detects the pump motor runs continuously.

* The EBCM detects the pump motor is binding or stalled.

* The EBCM detects an open/high resistance on the ground circuit.

* The EBCM detects a short to ground or an open/high resistance on the B+ circuit.

Action Taken When the DTC Sets

* The ABS indicator illuminates.

* The red Brake indicator illuminates.

* The Stability Control indicator illuminates.

* The driver information center displays Service Brake Soon, Service StabiliTrak and Service Traction Control messages.

* The EBCM disables the ABS, the traction control system and the vehicle stability enhancement system for the duration of the ignition cycle.

Conditions for Clearing the DTC

* The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.

* The condition for the DTC is no longer present and the vehicle is driven at speeds greater than 15 km/h (10 mph) to complete the self test, then the EBCM will turn off the ABS indicator.

Diagnostic Aids

* Check for hydraulic leaks, air in the brake system or an improper brake bleed.

* Find out from the customer the conditions under which the DTC was set. This information may help duplicate the failure like the specific number of brake pedal applies in a row prior to the fault set.

Reference Information

Schematic Reference

Antilock Brake System Schematics [1][2]Antilock Brakes / Traction Control Systems

Connector End View Reference

Component Connector End Views 1-2 Shift Solenoid (SS) Valve (M30)

Description and Operation

ABS Description and Operation Description and Operation

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, perform the ABS Motor test with a scan tool. You should hear or feel the ABS pump motor turn ON and OFF.

• If the pump motor does not turn ON and OFF, refer to Circuit/System Testing.

Note:
To ensure the complete brake modulator and high pressure accumulator pressure relief procedure is allowed to occur, the brake controller must see one brake pedal apply with the engine running followed by a proper shutdown without applying the brake pedal.

2. Transmission in PARK, engine running, apply and release the brake pedal.

Note:
The ignition must transition to the OFF position without pausing at ACCESSORY and without applying the brake pedal. This ensures that the brake modulator and high pressure accumulator relief occurs. This process will take approximately 1-2 minutes.

3. Ignition OFF, key removed from the ignition, wait 2 minutes.

4. Ignition ON, observe the scan tool EBCM, Accum. Pressure Sensor parameter. The Accum. Pressure Sensor parameter should be greater than 11,000 kPa (1,600 psi) in less than 15 seconds.

• If less than 11,000 kPa (1,600 psi) or it takes longer than 15 seconds to build pressure, refer to Brake Hydraulic and Assist System Diagnosis (Two-mode Hybrid) Brake Hydraulic and Assist System Diagnosis.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the K17 EBCM.

2. Test for less than 1 ohms between the ground circuits listed below and ground:

* Terminal 13

* Terminal 38

• 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+ circuits listed below and ground:

* Terminal 1

* Terminal 25

• 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, replace the Q5 brake pressure modulator.

4. If all circuits test normal, replace the Q5 brake pressure modulator and verify the DTC does not reset. If the DTC resets, replace the K17 EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Brake Pressure Modulator Valve Replacement Brake Pressure Modulator Valve Replacement

* Control Module References Control Module References for EBCM replacement, programming and setup

pro multis · About Operation CHARM