C0552
DTC C0552 or C121D
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 provide an overview of each diagnostic category.
DTC Descriptors
DTC C0552 00
- Improper Shutdown Malfunction
DTC C121D
- Electronic Brake Control Module Internal Malfunction
Diagnostic Fault Information
Circuit/System Description
The electronic brake control module monitors the number of Vehicle in Service Mode and Vehicle OFF cycles. When it detects that a Vehicle OFF cycle was incomplete or non-existent this fault will set. This means the fault reports a problem that occurred at the end of the previous ignition cycle. If this occurs during an electronic brake control module service operation, any calibrations or offsets learned during that service operation may not be properly stored in memory.
Conditions for Running the DTC
* Vehicle ON or Vehicle in Service Mode.
* The ignition voltage is greater than 10 V.
* The electronic brake control module is initializing.
Conditions for Setting the DTC
A Vehicle OFF cycle was interrupted before completion. Or power was removed from the module; with the Vehicle ON, the vehicle moving, and the brake applied.
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
This DTC may set if battery voltage drops below 8 V with the Vehicle ON or Vehicle in Service Mode.
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 Testing
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 each ground circuit terminal listed below and ground:
* Terminal 13
* Terminal 38
• If 10 ohm or greater
1. Ignition 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 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 K17 electronic brake control module.
5. Cycle the Vehicle OFF then to Vehicle in Service Mode.
6. Verify DTC C0552 or C121D is not set.
• If DTC C0552 or C121D is set
Replace the K17 electronic brake control module.
• If DTC C0552 or C121D is not set
7. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
Control Module References Programming and Relearning for electronic brake control module replacement, programming and setup