1986 golf blows fuse for the brake lights every time I depress the brake pedal. It is not the brake switch. Running lights stay lit

Turn signal and brake lights operate from a different switch. The brake light switch is under the dash behind the brake pedal. Look under the dash and follow the brake pedal up until you see a switch which the pedal operates. Normally a white plastic switch with two wires. Disconnect the two wires and touch them together. If brake lights come on replace the switch. If not use a 12 volt test light to see if there is current to one of the wires. If not, check for a blown fuse. This should solve your problem. If not, contact me for further information,

It could be the turn signal switch, since the brake wire travels through the turn switch after it leaves the brake switch and then goes to the bulbs. That is how you get a steady brake light on one side, and a blinking light on the turning side. The rear turn signal lights and brake lights share the same filament in the bulbs (and the same wire). The wire on the turning side has to first travel through the flasher relay.
If you have a test light, first check for power out of the brake light switch with the pedal depressed. Then check for power in and power out at the turn switch connector-power in on the brake light wire and power out on either of the wires going to the rear bulbs-if no power out, the turn switch is bad-brake pedal still depressed so you still have the signal.

you have faulty brake light switch or one of brake light bulb sockets or wiring have a short.

You either have a bad brake light switch or a bad fuse that powers your brake lights. Go to your fuse panel and check the fuse first. If it checks good then check the brake light switch. The switch will be located on the brake pedal at the top. There should be two wires into the switch. One will have power at all times. as you depress the brake pedal it makes the connection in the switch to the other wire which then sends power to the brake lights and illuminates the bulbs. Use an electrical tester to make sure you have power in and power out when the brake pedal is depressed.

on your brake pedal there is a switch that controls your brake lights over time it comes to lose just enough for the switch won't come in contact with the pedal

lamp failure light on possible because the SECOND filament in your STOP/TAIL Light Bulb is burned out- change one side and check fail lamp again- repeat on other side- fail lamp works off of resistance-burned or blown bulb is only way it lights unless you have a wiring issue

The most probable cause is a sticking brake light switch. The brake light is activated by a small switch mounted under the driver's side, up near the leg of the brake pedal. That switch is spring backed so that when you depress the pedal the shaft of the switch is let forward and turns on the brake light. That switch sometimes comes loose or half cocked in the housing and stays activated all the time until you let the brake pedal loose and the leg of the pedal depresses the switch shaft just enough to turn off the brake light. The solution is to replace the switch, at about 15 bucks at your Advance Store. or 10 bucks plus shipping on the internet. You can check when you leave the vehicle to see if the brake lights are still on. Mind you, this does not happen all the time as sometimes it is cured by the action of the brake pedal knocking the shaft back in line

It sounds like it is time for a new brake light switch, It is located just under the top of the brake pedal. Not that difficult to change.

Good Luck, and I hope this helps.

When you depress the brake pedal, the brake pedal will move away from the brake light switch and cause a close circuit and the brake lamps light up. There is a rubber bunk on the pedal which pushes against the brake light switch to shut it off when you release the brake pedal. Most likely this rubber bunk has either fallen off or disintegrated leaving a hole in the brake pedal so there is nothing to push against the switch to shut it off. Look up the brake pedal until you see the brake light switch, then depress the brake pedal to see if the rubber bunk is still there. It is easy to replace. Or you can use some double sided adhesive tape and a coin and stick the coin over the hole in the brake pedal.

check both brake lights for moisture getting into them.