i have a 2001 valvo s80 with outside brake lights always on. the third brake lamp works when pedal is pressed. so i assume switch is good. can some pleaase help. thank you

 

It sounds like you may have your lights turned on. I know that may sound painfully simple, but have you checked to ensure that you've switched your lamps to off?

 

You'll want to check the brake light relay. Look in the trunk behind a panel on the left side. There are relay diagrams on-line that will assist you in finding the right one. Most of the modules are identical, so you can test your module by swapping it with another that is known to work.

The brake light relay gets a lot of use, so it's one of the first to fail. With frequent use, the contacts inside the relay can form 'pits', that grow larger over time. Eventually, the pits will bridge the contact, and your lights will be stuck on. The problem can be intermittent at first, but it will get worse over time.

You could pry open the relay and clean the contacts, but a new replacement relay is reasonably cheap to buy. If your Volvo is starting to have this problem, you might consider ordering a spare or two.

M