C0299
DTC C0299
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 C0299 00
- Brake Booster Pressure Sensor Performance
DTC C0299 5A
- Brake Booster Pressure Sensor Performance Plausibility Failure
Diagnostic Fault Information
Circuit/System Description
The electronic brake control module (EBCM) provides power and ground circuits to the power brake booster actuator. The power brake booster actuator converts electrical inputs into a mechanical force to apply the brake booster to assist the driver as necessary in stability control. The EBCM monitors the vacuum level in the power brake booster, and will set a DTC if the vacuum is too low.
Conditions for Running the DTC
C0299 00
* Ignition ON.
* Ignition voltage is greater than10 volts.
C0299 5A
* Ignition ON.
* Engine Running.
* Ignition voltage is greater than 10 volts.
Conditions for Setting the DTC
C0299 00
The EBCM detects a short to ground, open/high resistance or a short to voltage on the power brake booster actuator control circuits.
C0299 5A
* No vacuum is detected in the power brake booster for approximately 10 seconds after start-up.
* Low vacuum is detected in the power brake booster for approximately 60 seconds or longer after start-up, or is detected while driving.
Action Taken when the DTC Sets
* The EBCM disables the active vacuum booster for the duration of the ignition cycle.
* A DIC message and/or a warning indicator may be displayed.
Conditions for Clearing the DTC
* The condition for the DTC is no longer present.
* The EBCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.
Reference Information
Schematic Reference
Hydraulic Brake Schematics ([1][2]Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
Description and Operation
Brake Assist System Description and Operation (Hydraulic Assist) (Brake Assist System (Hydraulic Assist))Brake Assist System Description and Operation (Vacuum Assist) (Brake Assist System (Vacuum Assist))
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 Testing
C0299 00
1. Ignition OFF, disconnect the harness connector from the power brake booster actuator.
2. Test for less than 25k ohm of resistance between the harness connector terminal 5 and ground.
• If greater than 25k ohm, test the ground circuit for an open/high resistance.
3. Connect a test lamp between the actuator harness connector terminal 1 and terminal 5.
4. Ignition ON, command the Active Brake Booster to ON and OFF with a scan tool.
• If the test lamp remains OFF during the commands, test for a short to ground or an open/high resistance on either control circuit. If the circuits test normal, replace the electronic brake control module EBCM.
• If the test lamp is always ON, test the control circuits for a short to battery positive. If the circuit tests normal, locate and repair the source of the vacuum leak.
5. If all circuits test normal, test or replace the vacuum brake booster assembly.
6. If all circuits test normal, and no vacuum leaks were found, replace the electronic brake control module (EBCM).
C0299 5A
Verify DTC C0299 5A is not set.
If the DTC is set, repair the source of the vacuum leak. Refer to Brake Assist System Diagnosis (Vacuum Assist) (Component Tests and General Diagnostics)Brake Assist System Diagnosis (Hydraulic Assist) (Component Tests and General Diagnostics).
Component Testing
C0299 00
1. Ignition OFF, disconnect the harness connector at the power brake booster actuator.
2. Test for infinite ohms of resistance between the actuator terminal 1 and ground.
• If less than infinite ohms, replace the vacuum brake booster assembly.
3. Test for 2-3 ohms of resistance between terminals 1 and 5 at the power brake booster actuator.
If the test is infinite resistance, replace the vacuum brake booster assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Power Vacuum Brake Booster Replacement (Without JF4) (Power Vacuum Brake Booster Replacement (Without JF4))Power Vacuum Brake Booster Replacement (With JF4) (Power Vacuum Brake Booster Replacement (With JF4))
* Control Module References (Control Module References)for EBCM replacement, setup, and programming