C12E9
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 Malfunction
DTC C0110 61
- Pump Motor 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. There are three solid state relays in the electronic brake control module that operate the pump. The pump motor runs every few brake stops in order to fill the high pressure accumulator with brake fluid.
Conditions for Running the DTC
* Vehicle ON or Vehicle in Service Mode.
* Ignition voltage is greater than 10 V.
* The system enable relay is ON.
* The pump motor has been commanded ON, OFF and ON again.
Conditions for Setting the DTC
* Brake system hydraulic leak
* Excessive brake pedal applies
* Improper hydraulic brake system bleed
* The electronic brake control module detects a short to ground or an open/high resistance on the B+ circuit.
* The electronic brake control module detects an open/high resistance on the ground circuit.
* The electronic brake control module detects the pump motor runs continuously.
* The electronic brake control module detects the pump motor is binding or stalled.
* The brake pressure accumulator is not charging.
* If in the Vehicle in Service Mode for an unspecified length of time, the high pressure accumulator may relieve brake pressure enough to set this DTC.
Action Taken When the DTC Sets
* The ABS indicator turns ON.
* The red brake indicator turns ON.
* The traction control/stability control indicator turns ON.
* The Service Brake Assist and Service StabiliTrak messages are displayed on the driver information center.
* The electronic brake control module disables the antilock brake system, the traction control system and the electronic stability program for the duration of the drive cycle.
Conditions for Clearing the DTC
* The condition for setting the DTC is no longer present.
* The history DTC will clear after 40 consecutive fault-free drive cycles have occurred.
Diagnostic Aids
* Check for hydraulic leaks, air in the brake system or incorrect brake bleed.
* DTC C0110 may set if the vehicle has been in the Service Mode for an extended period of time.
* Find out from the customer the conditions under which the DTC was set. This information may help duplicate the concern 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 Hybrid/EV Battery Pack X1
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 Programming and Relearning for scan tool information
Circuit/System Verification
Note: DTC C0110 may set if the vehicle has been in the Service Mode for an extended period of time.
1. Vehicle in Service Mode.
2. Verify that DTC C029C is not set.
• If the DTC is set
If the DTC is set, refer DTC C029C, C120C, C129A-C129F, C12B1, or C12F8 C029C.
• If the DTC is not set
3. Perform a brake hydraulic system test, refer to Brake Hydraulic and Assist System Diagnosis Brake Hydraulic and Assist System Diagnosis.
• If the brake hydraulic system test does not pass
Repair as necessary.
• If the brake hydraulic system tests normal
4. Refer to Circuit/System Testing.
Circuit/System Testing
Note: DTC C0110 may set if the vehicle has been in the Service Mode for an extended period of time.
1. Vehicle OFF and all vehicle systems OFF, disconnect the harness connector at the K17 electronic brake control module. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohm between the ground circuit terminal 13 and ground:
• If 10 ohm or greater
1. Vehicle OFF.
2. Test for less than 2 ohm in the ground circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, repair the open/high resistance in the ground connection.
• If less than 10 ohm
3. Vehicle in Service Mode.
4. Verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.
• If the test lamp does not illuminate and the circuit fuse is good
1. Vehicle OFF.
2. Test for less than 2 ohm in the B+ circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, verify the fuse is not open and there is voltage at the fuse.
• If the test lamp does not illuminate and the circuit fuse is open
1. Vehicle OFF.
2. Test for infinite resistance between the B+ circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the Q5 brake pressure modulator.
• If the test illuminates
5. Replace the Q5 brake pressure modulator.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Electronic Brake Control Module with Brake Pressure Modulator Valve Replacement Electronic Brake Control Module with Brake Pressure Modulator Valve Replacement
* Control Module References Programming and Relearning for electronic brake control module replacement, programming and setup