Antilock Brake System - Hybrid (HP5)
DTC C0561
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC C0561 4B
- System Disabled Information Stored Calibration Not Learned
DTC C0561 54
- System Disabled Information Stored Temperature High
DTC C0561 59
- System Disabled Information Stored Component Protection Time Out
DTC C0561 71
- System Disabled Information Stored Invalid Serial Data Received
DTC C0561 72
- System Disabled Information Stored Alive Counter Incorrect
DTC C0561 74
- System Disabled Information Stored Value of Signal Protection Calculation Incorrect
DTC C0561 75
- System Disabled Information Stored Signal Above Allowable Range
Circuit/System Description
The electronic brake control module (EBCM) receives serial data messages from other modules which are needed to perform antilock brake system (ABS), vehicle stability enhancement system (VSES), or traction control system (TCS) functions.
Conditions for Running the DTC
* Ignition ON.
* Ignition voltage is greater than 10 V.
Conditions for Setting the DTC
The EBCM receives an invalid serial data message from another module which causes EBCM to deactivate ABS, VSES, TCS, etc.
Action Taken When the DTC Sets
* The EBCM disables the antilock brake system (ABS), traction control and the vehicle stability enhancement system (VSES) 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.
* It may take 2 ignition cycles to clear this DTC.
* The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.
Reference Information
Schematic Reference
Antilock Brake System Schematics (2 Mode Hybrid) (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
ABS Description and Operation (Antilock Brake System - Hybrid)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
1. Verify that no other DTCs are set
• If DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code Descriptions)
2. Verify the 12 V battery state of charge is at an acceptable level.
• If the battery state of charge is low, charge the 12 V battery. Refer to Battery Charging (Battery Charging).
3. Using the scan tool, perform the EBCM relearn.
Note: To ensure the complete brake modulator and high pressure accumulator (HPA) 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.
4. Engine running, press 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 HPA pressure relief occurs. This process will take approximately 1-3 minutes.
5. Turn the ignition OFF without pausing at ACCESSORY and without applying the brake pedal. Remove the key from the ignition.
6. Wait 3 minutes until the brake modulator and HPA pressure relief is complete.
7. Ignition ON, brakes unapplied, verify the following EBCM scan tool parameters are within the specified values:
* Master Cylinder Pressure Sensor Input - Less than 100 kPa (15 psi)
* Rear Brake Pressure Sensor - Less than 100 kPa (15 psi)
* Brake Pressure Sensor Input - Less than 100 kPa (15 psi)
* Accum. Pressure Sensor - Less than 800 kPa (116 psi)
• If any of the parameters are not within the specified range, replace the brake pressure modulator valve (BPMV).
8. Brakes unapplied, verify the following EBCM scan tool parameters are within the specified values:
* BMC Prim. Piston Pos. Sen. 5 V Reference Position - Between 4.75 V and 5.25 V
* BMC Primary Piston Position Sensor A - Less than 0.8 V
* BMC Primary Piston Position Sensor B - Greater than 4.2 V
• If any of the parameters are not within the specified range, refer to DTC C0277, C120C, C129A, C129B, C129D, C129E, C12B1, or C12F8 (C0277).
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedures:
* Brake Pressure Modulator Valve Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for EBCM replacement, setup, and programming