C0545 on Cadillac: How to Diagnose & Fix
Electronic Stability Control Inhibit
1 Cadillac model · 1 documented issue · 1 critical · $1,500-$2,600 repair
C0545 on Cadillac by model: symptoms, diagnosis and fix
XT6 owners report a "Steering Assist is Reduced — Drive with Care" or "Service Power Steering" message in the driver information center, usually with a noticeable increase in steering effort. GM bulletin 20-NA-215 covers this condition on the XT5 and XT6 and ties it to DTCs C0460 and/or C0545 stored in the power steering module. The XT6 uses a belt-drive electric rack with the motor and control module integrated into the steering gear, so an internal fault or a torque-sensor signal fault sets the code and the module deliberately cuts or reduces assist rather than allowing erratic assist. Steering is still mechanically connected — the car remains steerable — but effort rises sharply, which is most alarming at parking-lot speeds or in an evasive maneuver. Owners also describe a separate, milder version where assist fades after sustained low-speed maneuvering and returns once the system cools; that thermal derate is normal protection, not a failed rack, and it clears itself.
Common Symptoms
- "Steering Assist is Reduced — Drive with Care" message in the DIC
- "Service Power Steering" warning
- Steering suddenly becomes very heavy, especially at parking speeds
- Assist cuts out intermittently and returns after a restart
- Sometimes accompanied by other electrical warnings on the same drive
How to Fix
Have the power steering module scanned first. A stored C0460 or C0545 per bulletin 20-NA-215 calls for replacement of the complete steering gear assembly — the module is not serviced separately. After the rack is replaced the steering angle sensor must be recalibrated with a capable scan tool or the system will not function and the message will return. Out of warranty a rack and calibration typically runs roughly $1,500-$2,600 at a dealer. Before replacing anything, rule out the thermal derate (assist returns after cooling, no stored code) and a weak battery or poor ground, either of which can trigger a false assist-reduced message on this platform. The XT6's powertrain warranty does not cover this, but the 4-year/50,000-mile bumper-to-bumper coverage does.
Sources for this issue (3)
C0545 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 C0545 mean on a Cadillac?
C0545 stands for "Electronic Stability Control Inhibit." This chassis/brake code indicates the electronic stability control (ESC) system has been inhibited, meaning it has temporarily disabled itself because of a related fault or invalid condition. Stability control helps keep the vehicle from skidding by selectively braking wheels and managing engine power, and it relies on inputs like wheel speed, steering angle, and yaw sensors. When one of those inputs is missing or implausible, the system shuts itself off and sets this code. Often it is a secondary code triggered by another underlying fault rather than a problem with stability control hardware itself. On Cadillac it is documented across 1 model: XT6.
What are the most common causes of C0545?
The most common causes of C0545 are: Faulty or dirty wheel speed sensor, Steering angle sensor fault or needing calibration, Yaw rate / lateral acceleration sensor fault, Low brake fluid or related brake system fault, Damaged wiring or connectors to a sensor, Related ABS/traction control fault setting this as secondary, Faulty ABS/ESC control module. The specific cause varies by vehicle.
How much does it cost to fix C0545 on a Cadillac?
Published repair estimates on Cadillac range from $1,500 to $2,600 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for C0545 on a different make?
View C0545 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.