Smart Fortwo Wiper Failure: Switch vs Wiring Issue Fix

Had a similar issue with my Smart Forfour diesel from 2014. As someone with some hands-on experience working on cars, I first thought it was the windshield wiper motor, but it turned out to be simpler. The rain sensor and wiper control unit had a loose connection causing intermittent failures. Took it to my regular workshop where they diagnosed a damaged wire in the cable harness near the steering column connector. Total repair was 95€ including diagnostic and fixing the connection. The mechanics mentioned these issues are somewhat common in Smart vehicles from that era, especially when the original wiring starts showing age-related wear. The cruise control buttons on the same stalk were also acting up before the repair. Before suggesting more specific solutions, could you share: Does the wiper system make any noise when activated? Are both wipers affected or just one? Did the problem start suddenly or gradually? Have you noticed any other electrical issues with steering column controls? This would help determine if your issue matches what I experienced or points to a different root cause with your car wipers.

Thanks for the input. Latest service was done at 122000 KM about 2 months ago. No noise at all when activating the turn signal or wiper controls. Both wipers are affected and stopped working at the same time. The issue started suddenly during heavy rain. No other electrical problems with steering column controls so far. The wiper motor seems to be getting power according to my basic voltage test, which makes me lean toward the switch being the culprit. Did anyone have success just cleaning the switch contacts, or is replacement typically needed?

Thanks for those details. Your symptoms actually sound identical to what I dealt with in my Smart. Even with power reaching the wiper motor, the root issue can still be in the control circuitry rather than the switch itself. In my case, cleaning the switch contacts made no difference. The workshop eventually found that water had gotten into the wiper switch assembly through a deteriorated seal, causing corrosion on the internal contacts. Simply cleaning wouldnt fix the permanent damage. The complete wiper switch replacement including labor ran about 180€. While they had the steering column apart, they also checked the turn signal and cruise control connections since they share the same housing. Before going for a full replacement though, have you checked: Fuses related to the wiper system, Connections at the wiper motor plug, Ground connection at the motor mount These are worth verifying since theyre free to check. But given the sudden failure during rain and complete loss of function, I strongly suspect youll end up needing the switch assembly replaced like I did. The good news is the repair completely resolved the issue and the new switch has been trouble-free for 2 years now.

Thanks everyone for the helpful responses. After checking the suggested points, I found something interesting, the ground connection at the motor mount was indeed quite corroded, but cleaning it didnt solve the problem. Took it to a repair shop yesterday and turned out my suspicion about the switch was correct. The wiring harness connections were fine, but the wiper switch had failed internally. The mechanic showed me the corroded contacts inside the old unit after replacing it. Total cost was 165€ for parts and labor, slightly less than expected. They also checked the rain sensor and other steering column controls while they were in there. All working perfectly now, even during the heavy rain we had this morning. For anyone finding this thread later with similar symptoms: If your wipers suddenly stop with no noise, and basic voltage tests show power at the wiper motor, definitely get the switch assembly checked first before replacing more expensive components.