I have a 2001 Toyota Prius, and I am having problems with the cruise control. It only works intermittently. There does not seem to be much of a pattern, but I have noticed the following:
1. It usually works if I turn it on when I start the car before I drive at all.
2. It sometimes works when I activate it before hitting 20-25 MPH.
3. If it will not turn on, it will never work during the rest of the trip. The car must be turned off, and sometimes it will work when the car is restarted, but not always.
4. It seems worse in the winter, but does not seem to be tied directly to weather or road conditions.
Any advice or repair tips would be appreciated as I like to use the cruise control daily.
Check the brake light operation, especially the center brake light. A burned-out bulb may disable the cruise control.
A burned-out center brake light was causing similar issues with the cruise on my 93 Caprice. It’s easy to miss. I replaced the bulb and the cruise has been working since (7 years).
Keep checking the brake lights on the vehicle. You may have a misadjusted or misaligned brake switch. This model also uses a hydraulic brake light switch that may be defective and shutting off your cruise control. A good mechanic will be able to check this out.