Buick ABS & Traction Issues Point to Speed Sensor Fault

As someone with moderate experience working on cars, I faced almost the exact same issue with my 2002 Buick Regal last winter. The symptoms were identical, ABS light staying on and traction control malfunction. Initially, I thought it was just a sensor issue. After taking it to a workshop, they performed a complete diagnostic scan which revealed the ABS control unit itself was defective. The ECM was receiving incorrect signals, causing the ABS and traction control systems to malfunction. The repair involved replacing the entire ABS control unit, which cost around 1000 Euro. Since the replacement, all systems have been working perfectly, no more ABS light, and the traction control is fully functional again. Before suggesting specific solutions, could you provide: Current mileage on your odometer, Any unusual noises when braking, Whether the transmission shows any issues, If you notice any other warning lights, When these symptoms first appeared This information would help determine if your issue matches what I experienced with my Regal or if it might be something different.

I am having the same issue at 175351 KM. No unusual sounds while braking and the transmission runs smoothly. The dashboard warning lights started appearing about a week ago. I had a mechanic scan the system and it points to faulty wheel speed sensors. However, I am hesitant about replacing the ABS module since the speedometer works fine. The cost estimate seems quite high and I want to ensure we are fixing the actual problem rather than just throwing parts at it. Has anybody successfully fixed this by just replacing the sensors first?

Thanks for providing those details about your Buick Century. Since I went through this with my Regal, I can share what I learned. Even though your speedometer works fine, faulty wheel speed sensors can still trigger ABS and traction control issues. The diagnostic codes pointing to speed sensors make sense. In my case, I actually regret not trying the sensor replacement first before jumping to the full ABS module replacement. The wheel speed sensors are much more affordable and commonly fail at higher mileages like yours. My suggestion based on my experience would be to: 1. Replace the wheel speed sensors first since the diagnostic scan specifically points to them 2. Clear the fault codes from the ABS system 3. Test drive and monitor if the dashboard warning lights return If the ABS light and traction issues persist after replacing the sensors, then you might need to consider the control module. But starting with the sensors is the smarter and more cost-effective approach, especially since your speedometer and transmission are working normally. Just have the shop verify which specific sensors are showing faults in their diagnostic scan before replacing them. Sometimes only one or two sensors need replacement rather than all four.

Thanks for that detailed advice about the sensors. I'll definitely try replacing just the wheel speed sensors first since the input from my speedometer and transmission seems normal. The dashboard warning lights are annoying but at least now I have a clear starting point for repairs. Makes sense to take the more economical approach rather than rushing to replace the entire ABS module. I'll have my mechanic check the diagnostic codes again to identify exactly which sensors are problematic. Will update once I get this fixed to let others know if the sensor replacement solved my odometer and ABS issues. Really appreciate everyone sharing their experiences with similar problems.