86 blowing brake light fuse

[jeff1hughes]

every time I hit the brakes my fuse blows. Any one have an idea on this one?

[jester911]

Jeff,
The brake lights are activated by 2 hydraulic switches that are in the master cylinder. Unless there is a short at the switches it may actually be in one of the brake lights them self.

You might try putting power to the brake lights seperate from the system to see if there is a short there

[jeff1hughes]

I unplugged each light and the fuse still blew. Is it possible that the switches might be shorting out?

[msailer]

I have seen this before on a '84
Do you have Cruise control? If so, your module might be bad.
Find the wire that brings 12v to cruise control module and remove it from the fuse block and try again. Work with my fried who was blowing the fuse everytime he stepped on the brakes.

[jeff1hughes]

That was the second thing I did, after the light bulbs. Still popped the fuse. Next I removed the wire for the brake circuit, now I need to test drive and see if the cruise control works or not. I just bought the car and found this little gremlin hiding out

[jester911]

Jeff, the switches are cheap and easy to replace. Make sure you check to see if yours is the 2 prong or 3 prong. Mine were 3 prong but not all cars had the same
You can get them here from our host.

[jeff1hughes]

where are the switches at, I am used to working on a 71, master cyl. at the pedal, this obviously doesn't have the same set up, being power and all.

[jeff1hughes]

I found it! It was in the 3rd brake light, the coating around the spade terminals for the hot and the ground both wore through by the metal support clip--arcing and shorting out the system. Nothing a little friction tape with electrical tape covering can't fix!