VW Eos Cruise Control Failure & Check Engine Alert

I had a similar issue with my 2008 VW Passat last summer, and as someone with moderate experience working on VWs, I can share what worked in my case. The symptoms were exactly the same, cruise control stopped responding and the dashboard light appeared. After taking it to my regular workshop, they found the throttle position sensor cable had a damaged connection, which was causing intermittent signal issues to the cruise control system. The repair involved: Testing the pedal switch connections, Checking the fuse box (all fuses were good), Replacing a worn cable harness connected to the throttle position sensor, Clearing the error codes Total cost was 95€ including parts and labor. The repair took about an hour. Before suggesting more specific solutions, could you share: Have you checked if the brake pedal switch is working properly? Does the throttle respond normally during regular driving? Are there any other electrical issues with other systems? What specific error code did the scan show? These details would help determine if your issue matches what I experienced or if it might be something different in the cruise control system.

Thanks for the detailed reply. Just had my last service at 75000km where they did a full electrical check. No other electrical issues noted and throttle responds perfectly during normal driving. The error code shown was P0571. The brake pedal switch seems to work fine since the brake lights illuminate normally when pressed. I just want to fix this before my next long trip.

Thanks for providing those extra details. Based on the error code P0571 you mentioned and my experience with the same issue on my VW, this sounds like a cruise control brake switch signal problem, even though your brake lights are working. On my car, it turned out that while the brake lights worked fine, the separate speed sensor circuit for the cruise control system wasnt getting the right signal. The brake pedal actually has dual switches, one for the lights and another for the cruise control system. The fix involved: Replacing the brake pedal switch assembly (around 45€ for the part), Recalibrating the new switch, Clearing the error codes After this repair, my cruise control system worked perfectly again. Since your symptoms and error code match my experience exactly, Id strongly recommend checking the brake pedal switch assembly first before exploring other components of the cruise control system. Also worth mentioning, the fuse box connections to these switches can get corroded over time. While replacing the switch, have the technician check the fuse box connections too. This could save you from future issues with the cruise control system.

That makes a lot of sense about the dual switch system, I had no idea the brake pedal switch had separate circuits for the brake lights and cruise control. The 45€ part cost seems reasonable, especially since the steering wheel and other controls are working fine. My mechanic can definitely check those fuse box connections while doing the switch replacement. Thanks for explaining how the cruise control system integrates with the brake components. I'll schedule the repair soon since I want this fixed before my road trip. Will report back on whether replacing the pedal switch assembly resolves the issue.