Subaru fuse conundrum

On my 2000 Subaru Legacy GT wagon, I have started blowing tail light fuses. I have replaced it 3 times now - so it is clearly not JUST the fuse that is the problem. However, I have also noticed that when I replace the blown fuse the ABS light comes on, and the cruise control stops working. At some point with in a few days the fuse blows, then the ABS light goes out, and the cruise control starts working.



Otherwise car fine.



Can these be related?

I’m sure they are related. Check the rear tail light area for a trailer connection. Trouble can happen with that. If you don’t find the trouble there then you will have to search for the trouble. A wire is touching ground somehow.

The ABS light sounds like it may be a seperate issue. You may need to get that checked out.

It is never “just the fuse.” They blow for a reason. You need to find and correct that reason.

Thanks for your posts - yes, I realize that fuses blow for a reason, especially when it happens repeatedly.

I am not so sure that the ABS light coming on and going off is a separate issue - because it seems to coincide with the failure of the fuses. But is it possible that somehow one is triggering the other?

Sometimes bulbs or bulb sockets can create a problem, It is not a fuse problem so start with the taillight,brake bulbs. Replace them, look for any problems. If you have a vtvm or tvm (vacuum tube volt meter or transistorized volt meter ha ha) check for proper voltage and ground when you replace the bulbs.

I agree; inspect the bulbs closely. Sometimes a filament in a brake light bulb will sag and make contact with another filament.

Something else to check on Subarus is this, and I’ve seen it a number of times.
If you look at the lead contacts on the bulbs closely they should look like little domes. Sometimes vibration of the bulb contact on the socket contact will wallow the lead dome off and give it a concave surface.

This leads to a poor contact, which means high resistance in the circuit. This in turn leads to current surging and heat and can cause a blown fuse.
Not saying this is the problem, only a possibility.

If you do have a trailer connection, that would be a good place to start. I would suggest that second would be the brake light switch. Usually they are cheap and easy to replaced.

Great - this and the previous post are very helpful. I will check these out tomorrow. For the record, no, no trailer hitch.

I also checked - both brake lights and back up lights are un-affected as well.

Your vehicle should have trailer connector hidden in the rear area. I think it is on the driver’s side. I assume fuse #5 is the one blowing out. The fuse supplies power also to the front marker lights and the license plate lights.

Here is a link to a site that you may be interested it.
http://www.ultimatesubaru.org/forum/forumdisplay.php?f=3

ok4450- thank you, thank you, thank you!
Your post led us to the solution. We removed and inspected all the taillight bulbs and all of them were concave instead of like little domes as you described…but even worse,on one of the dual filament ones both contacts had sort of melted and fused together. We replaced all the bulbs, and voila, no more blown fuses, ABS light AND the cruise control works.
I am so pleased and thanks to all posters.

Another good call and case solved by OK4450. Thanks for the feedback on this.