C0561-71 - System Disabled, Information Stored, Invalid Serial Data
| Light color | Amber |
|---|---|
| Urgency | Service soon (amber) - stability and ABS are offline |
| Safe to drive | Yes, with caution - braking still works, but no ABS or traction assist |
| Common cause | Wheel speed sensor fault or bad EBCM ground sending corrupt CAN data |
| DIY or shop | Either |
C0561-71 means the Electronic Brake Control Module (EBCM) received serial data it could not validate and responded by disabling StabiliTrak and ABS. The full description is 'System Disabled, Information Stored - Invalid Serial Data Received.' The sub-code 71 identifies the failure type as invalid serial data, distinguishing it from other C0561 variants tied to voltage or internal faults.
This is almost always a secondary code. GM's own service procedure (PIT4169F) directs technicians to clear all other DTCs first and identify the upstream fault before touching the EBCM. Replacing the brake module for this code alone is a common and costly mistake.
What the code actually tells you
The EBCM communicates with other modules over the CAN bus - the engine control module (ECM), the body control module (BCM), and the steering angle sensor, among others. When one of those modules sends a signal the EBCM cannot reconcile, it flags C0561 with sub-code 71 and shuts itself down rather than risk acting on bad data.
Affected systems: StabiliTrak (GM's electronic stability control), ABS, and traction control are all disabled. Normal friction braking is unaffected. Most drivers also lose cruise control engagement because that system relies on stable vehicle speed data from the EBCM.
On the dashboard you will see a 'Service StabiliTrak' or 'Service Stability System' message, paired with the ABS and traction control indicator lights. The stability system light - a car with skid marks - may also illuminate. See the related guide on how systems shut down without an obvious warning for broader context on module-level fault handling.
- StabiliTrak / Stability ControlAmber
- Meaning: Electronic stability control is disabled; the EBCM has flagged a data integrity problemRecommended action: Scan for all DTCs across all modules before diagnosing the EBCM
- ABS Warning LightAmber
- Meaning: Anti-lock braking is offline because the EBCM has suspended operationRecommended action: Drive with extra stopping distance; normal brakes work, ABS does not
- Traction Control OffAmber
- Meaning: Traction control has been disabled alongside StabiliTrak by the same EBCM shutdownRecommended action: Do not attempt to re-enable via the button until the root fault is resolved
Root causes - start here, not at the EBCM
1. Wheel speed sensor fault. A failing speed sensor sends erratic or missing data to the EBCM. The module cannot compute vehicle speed accurately, so it shuts down. On GM trucks (Silverado, Sierra, Tahoe, Yukon, Escalade), the right rear wheel speed sensor is the most frequent offender. The connector sits near the rear differential housing and corrodes after road salt exposure. A replacement sensor costs $25-60 and takes under an hour.
2. Weak or failed battery. The EBCM is sensitive to voltage. A battery below 12.4V at rest, or one that drops during cranking, can cause the module to receive garbled CAN data and log C0561-71. Test the battery and charging system first - this is the cheapest and quickest check.
3. Poor EBCM ground. On GM trucks, ground straps G303 and G304 sit on the driver-side frame rail. Corrosion on those grounds causes voltage offset in the EBCM's reference signal, which gets interpreted as invalid data. Clean them to bare metal with 80-grit sandpaper and apply dielectric grease before reinstalling.
4. BCM communication fault. The body control module handles steering angle sensor data and yaw rate inputs. A BCM software glitch or its own ground fault can inject bad data onto the CAN bus. On the GMC Acadia, BCM communication problems are a leading cause of C0561-71. Scan the BCM module specifically for its own codes.
5. Steering angle sensor (SAS). If the SAS sends an out-of-range angle reading, the EBCM cannot trust its own stability calculations. This often appears after a wheel alignment without a SAS calibration reset.
Diagnostic procedure - step by step
Follow this sequence to avoid replacing parts unnecessarily.
- Step 1 - Full scan. Pull codes from every module: ECM, BCM, EBCM, and TCM. C0561-71 in the EBCM with a matching P-code or U-code in another module points directly to the upstream fault. GM's service bulletin PIT4169F requires all other codes to be addressed first.
- Step 2 - Battery and charging check. Voltage at the battery with engine off should read 12.4V or above. Charging voltage at idle should be 13.8-14.7V. Replace a weak battery before chasing sensor faults.
- Step 3 - Inspect wheel speed sensor connectors. Pull each rear connector and look for green corrosion or pushed-back terminals. A scan tool that shows live wheel speed data in the EBCM data stream will identify a dropout immediately - one sensor reading zero or erratic while the others track normally is a definitive find.
- Step 4 - Clean EBCM grounds. Even if the grounds look fine visually, clean them. High-resistance grounds cause intermittent faults that resist diagnosis.
- Step 5 - SAS reset. If recent steering or suspension work was done, recalibrate the steering angle sensor with a scan tool before clearing codes.
- Step 6 - Clear and road test. After any repair, clear all codes and drive a mixed 15-20 minute cycle. The EBCM needs multiple steering, braking, and speed events to complete its self-test.
For related CAN bus communication faults, the Honda U0416-68 module data code shows how similar invalid-data logic appears across different manufacturers.
Repair costs
Wheel speed sensor: $25-60 in parts, $80-150 at a shop for labor. EBCM grounds: under $10 in supplies, DIY. Battery replacement: $120-200 depending on group size. BCM reprogramming (if the BCM itself is faulty): $300-600 at a dealer since the module requires programming to the VIN. The EBCM itself averages $400-800 installed at a shop, but that is rarely the fix - exhaust that list above first.
Checking brake-related fault codes on other platforms may also be useful context. The brake pedal position sensor problems guide covers how pedal sensor faults can trigger secondary chassis codes in a similar way.
See also: Hyundai Santa Fe Bsd System, Cooling System Vw 2 0 Engine Parts Diagram.
Frequently Asked Questions
Q: Is it safe to drive with C0561-71?
A: The vehicle is drivable in the short term. Normal friction braking is fully functional; only ABS and StabiliTrak are disabled. That said, you lose anti-lock protection on slippery surfaces and electronic stability assistance in emergency maneuvers, so drive with more caution than usual and get it diagnosed promptly.
Q: Will C0561-71 clear itself after fixing the root cause?
A: Usually not on its own - you need a scan tool to clear the stored DTC after the repair. Once cleared, the EBCM runs a self-test during the next drive cycle and will not re-set the code if the underlying fault is genuinely resolved.
Q: Why do I have C0561-71 with no other codes?
A: It is uncommon but possible. The most frequent explanation is an intermittent wheel speed sensor dropout that did not set its own code, a borderline battery, or a corroded EBCM ground. Start with voltage and ground checks. If the code keeps returning with no other codes present, live data monitoring of wheel speeds and CAN bus traffic will usually reveal the intermittent fault.
Q: Does C0561-71 require dealer-only repair?
A: Not always. Replacing a wheel speed sensor, cleaning grounds, or swapping a battery are all DIY-friendly. BCM reprogramming and EBCM replacement do require dealer-level scan tools for module programming, so those steps are better left to a shop with a Tech 2 or equivalent.