C056D on Cadillac: How to Diagnose & Fix
Electronic Brake Control Module Internal Fault (manufacturer-specific)
1 Cadillac model · 1 documented issue
C056D on Cadillac by model: symptoms, diagnosis and fix
GM PI1294B covers 2014-2016 XTS vehicles with belt-drive electronic power steering RPO NJ2 when a Service Power Steering message appears intermittently after a cold start and C056D 3C, C0475 00 or U0131 is current or stored.
Common Symptoms
- Intermittent Service Power Steering message after a cold start
- C056D 3C
- C0475 00
- U0131
How to Fix
Have a qualified technician verify RPO NJ2 and the exact DTC subtypes, inspect the G111 ground and XTS 80A F72UA fuse connections, fully charge and test the battery, then update the power-steering control module under current GM programming procedures. Do not replace the steering gear, module or battery solely from this card.
Sources for this issue (1)
C056D code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does C056D mean on a Cadillac?
C056D stands for "Electronic Brake Control Module Internal Fault (manufacturer-specific)." C056D is a manufacturer-specific chassis code (frequently seen on GM vehicles) that generally indicates an internal hardware/electronics failure within the electronic brake control module (EBCM)/ABS assembly. When the module's own self-test detects a fault it cannot recover from, it disables ABS, traction control, and stability control and commonly triggers the 'Service StabiliTrak'/'Service Traction Control' messages. Because the fault is internal to the module, the usual repair is reprogramming or replacing the ABS/EBCM unit after confirming wiring and power/ground are good. Conventional braking still functions while the electronic aids are offline. On Cadillac it is documented across 1 model: XTS.
What are the most common causes of C056D?
The most common causes of C056D are: Internal EBCM/ABS module hardware failure, Corroded or damaged module connector/pins, Poor power or ground to the ABS module, Low battery voltage or charging system issues, Water intrusion/corrosion in the module, Module software/calibration corruption, Wiring faults at the brake module connector. The specific cause varies by vehicle.
How much does it cost to fix C056D on a Cadillac?
Repair costs vary widely with the root cause and Cadillac model; each issue on this page carries its own estimate where one is published.
Looking for C056D on a different make?
View C056D across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.