C0229 on GMC: How to Diagnose & Fix
Dropout of Front Wheel Speed Signals
1 GMC model · 1 documented issue · 1 critical · $180-$900 repair
C0229 on GMC by model: symptoms, diagnosis and fix
GMT800 SUVs commonly develop corrosion under the front wheel speed sensors or wear in the hub bearing assembly, which alters the low-speed wheel speed signal. The result is unexpected ABS activation at parking-lot speeds, longer stopping distances, and a pulsating brake pedal even on dry pavement. GM documented this condition in service bulletins and in safety recall 05V379, which covers 2000-2002 Yukon XL in salt-belt states, and owners frequently report replacing hub assemblies to cure it.
Common Symptoms
- ABS activates at 3-10 mph on dry roads
- brake pedal kicks back at low speed
- longer stopping distance near a stop sign
- ABS warning light
- grinding or humming from front wheel bearing
How to Fix
Scan ABS wheel speed data during a low-speed stop and compare left and right front sensor readings. If one sensor drops out, inspect for rust buildup under the sensor or excessive hub play; cleaning the sensor mounting surface may help temporarily, but many vehicles need a complete front hub/bearing assembly with integrated sensor. Clear ABS codes and road-test after repair.
Sources for this issue (2)
C0229 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 C0229 mean on a GMC?
C0229 stands for "Dropout of Front Wheel Speed Signals." This code sets when the ABS module detects a simultaneous loss (dropout) of both front wheel speed signals. Losing both front signals at once usually points to a shared fault — such as a common ground, power feed, connector, or harness problem affecting both sensors — rather than a single failed sensor. ABS, traction control, and stability control are typically disabled and the warning lights illuminate. Like other front-sensor codes, very rough driving can occasionally trigger it on an otherwise healthy system. On GMC it is documented across 1 model: Yukon XL.
What are the most common causes of C0229?
The most common causes of C0229 are: Damaged or corroded shared wiring/connector, Common ground or power-feed fault to both sensors, Both front wheel speed sensors dirty or damaged, Loose/corroded ABS module connector, Harness damage affecting both front circuits, Tone ring damage on both front wheels, Rough-road false trigger. The specific cause varies by vehicle.
How much does it cost to fix C0229 on a GMC?
Published repair estimates on GMC range from $180 to $900 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.
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.