C0550 on GMC
ECU Malfunction (Chassis)
C0550 on GMC vehicles indicates ecu malfunction (chassis). Au7o has documented this code across 1 GMC model — most commonly on Yukon XL. This is a chassis code indicating an internal Electronic Control Unit (ECU) malfunction, typically within the ABS/electronic brake control module or a related chassis controller. It sets when the module runs its internal self-checks (memory, processor, or output circuits) and detects a fault it cannot recover from. Because the affected controller often manages braking and stability functions, ABS, traction control, and stability control may be disabled, with their warning lights on. Base hydraulic braking generally still works. Typical repair costs on GMC range from $900 to $3,200, depending on the specific model and root cause.
Common Causes of C0550
- •Internal failure of the ABS/EBCM control module
- •Low or unstable supply voltage / weak battery
- •Corroded or loose module power and ground connections
- •Software or memory corruption (may need reflash)
- •Damaged module connector or harness
- •Electrical interference or recent jump-start/voltage spike
C0550 on GMC by Model
GMC Yukon XL(1 issue)
- Magnetic Ride Control (MRC) Shock/Strut Fluid Leak and 'Service Suspension System' Warnings2015-2020
Yukon XL Denali and other trims equipped with Magnetic Ride Control can develop leaking dampers and internal failure, leading to degraded ride quality and suspension fault messages. Owner reports commonly describe bouncy/floaty ride, clunking over bumps, and repeated 'Service Suspension System' alerts as the shocks lose damping control. This is frequently documented in owner forums and NHTSA complaints for K2XX-era Yukon XL with MRC.
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View C0550 across all makes →Frequently Asked Questions
What does C0550 mean on GMC?▼
C0550 stands for "ECU Malfunction (Chassis)." This is a chassis code indicating an internal Electronic Control Unit (ECU) malfunction, typically within the ABS/electronic brake control module or a related chassis controller. It sets when the module runs its internal self-checks (memory, processor, or output circuits) and detects a fault it cannot recover from. Because the affected controller often manages braking and stability functions, ABS, traction control, and stability control may be disabled, with their warning lights on. Base hydraulic braking generally still works. On GMC specifically, this code is documented across 1 model.
What causes C0550 on GMC vehicles?▼
Common causes on GMC: Internal failure of the ABS/EBCM control module, Low or unstable supply voltage / weak battery, Corroded or loose module power and ground connections, Software or memory corruption (may need reflash), Damaged module connector or harness. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix C0550 on a GMC?▼
Repair costs on GMC range from $900 to $3,200, depending on the specific model and root cause.
Which GMC models have C0550 documented?▼
Au7o has documented C0550 on 1 GMC model: Yukon XL.