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 C0299 00: Brake Booster Sensor PerformanceDTC C0299 5A: Brake Booster Sensor Plausibility Failure
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Power Brake Booster High Control Circuit | C0299 00 | C0299 00 | C0299 00 | C0299 5A |
Power Brake Booster Low Control Circuit | -- | C0299 00 | C0299 00 | C0299 5A |
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
Antilock Brake System Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
C0299 00
- Ignition OFF, disconnect the harness connector from the power brake booster actuator.
- Test for less than 25k ohm of resistance between the harness connector terminal 5 and ground.
- Connect a test lamp between the actuator harness connector terminal 1 and terminal 5.
- Ignition ON, command the Active Brake Booster to ON and OFF with a scan tool.
- If all circuits test normal, test or replace the vacuum brake booster assembly.
- If all circuits test normal, and no vacuum leaks were found, replace the electronic brake control module (EBCM).
| ⇒ | If greater than 25k ohm, test the ground circuit for an open/high resistance. |
| ⇒ | 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. |
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 |
Component Testing
C0299 00
- Ignition OFF, disconnect the harness connector at the power brake booster actuator.
- Test for infinite ohms of resistance between the actuator terminal 1 and ground.
- Test for 2-3 ohms of resistance between terminals 1 and 5 at the power brake booster actuator.
| ⇒ | If less than infinite ohms, replace the vacuum brake booster assembly. |
| ⇒ | If the test is infinite resistance, replace the vacuum brake booster assembly. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Power Vacuum Brake Booster Replacement
Control Module References for EBCM replacement, setup, and programming
