Peugeot 807 Cruise Control Failure

I had a similar cruise control problem with my 807. Did you check the connection to the speed sensor? Also, a faulty steering wheel control module can cause this. Is the dashboard light working?

Where exactly is the speed sensor located? Is there any way to test the steering wheel control module before replacing parts? Or is that a garage job?

The speed sensor is typically near the gearbox, but confirm with a repair manual for your engine type. Testing the steering wheel control module requires diagnostic equipment. If you're getting an error code related to it, and the cruise control is definitely the problem, I'd recommend professional help to avoid further issues.

Took it to the workshop. It was a defective cable or plug connection. Cost 95€ but cruise control is back.