Brake lights!

Maintenance/Repairs
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1

Hey car talk community. My brakes lights went out yesterday because of a blown fuse which I ended up replacing earlier today. After replacing the fuse noticed that only one side of my brake lights were working. I then went on to replace the side that was not working and ended up blowing my fuse again. The fuse will not blow if I have one good bulb installed but will blow if I have two good bulbs installed. Any advice would be appreciated. Thanks

2008 Toyota Corolla CE

2

Aren’t you perky!

Only, you left out the year of your of Corolla.

Makes a difference.

Tester

3

Closely inspect the “bad” socket for any corrosion, then blast it out with WD40.

4

Each socket is still able to transmit light if only one good bulb is being used at a time

5

It’s a 2008 Toyota Corolla CE

6

Make sure you are using the correct bulbs and the correct fuse.

7

Presuming the fuse and bulbs are the correct ones for the car, and they aren’t defective, there must be an unwanted current path somewhere that is overloading the circuit. It must not be a dead short, but just enough of a short that it allows one bulb to light, but not the other. I think what I’d do first is remove both bulbs and use an ohm meter to measure the resistance at the bulb socket to chassis ground. I expect OP will find one of the sockets measures a much lower resistance than the other. That’s the one that has the problem.

8

A fuse blows when the amps drawn on that circuit exceed the value of the fuse. Could be a short, but I doubt it based on your description. Is it possible that you are installing incorrect bulbs? Just because they fit into the socket does not mean they are the correct bulbs.

By the way a corroded wire can also result in an overload and blow the fuse.

9

A short is a short and blows the fuse…or starts the wire to melt and potentially start a fire.

10

It is extremely unlikely that using the wrong bulbs would cause the fuse to blow. There isn’t a tremendous difference in current draw among the bulbs that will fit that socket. I would look for a corroded connection, including in the fuse socket.