how come the fuse keeps gettin blown? HELP PLEASE!!!

**GenesisEG** · 05-10-2010 05:02 PM

The first thing I'd check is that the fuse is of a sufficient rating. If the fuse rating is too low and you overload the circuit, it'll blow the fuse. It's unlikely that this is the case, but since it's the easiest thing to check, it should be the first. Process of elimination, start with the simplest thing.

The second thing I'd check is that your GPS is not faulty. Try plugging something else (someone else's GPS or even the cigarette lighter) into the socket. If the fuse doesn't blow with the other GPS plugged in, your GPS is faulty. This could mean a damaged cable or a bent pin in the plug causing a short when you plug it in.

Personally, I don't believe it is a damaged wire behind the dash. If the active wire was damaged and shorting behind the dash, it'd blow every time you put a fuse in. Since it's only happening when you plug something in, it is more likely to be either the device you're plugging in, or the fuse.

The CD player appears to be running off the same fuse. Does the fuse blow when you are using the CD player?

**dougie_504** · 05-10-2010 05:39 PM

Originally Posted by GenesisEG

The first thing I'd check is that the fuse is of a sufficient rating. If the fuse rating is too low and you overload the circuit, it'll blow the fuse. It's unlikely that this is the case, but since it's the easiest thing to check, it should be the first. Process of elimination, start with the simplest thing.

The second thing I'd check is that your GPS is not faulty. Try plugging something else (someone else's GPS or even the cigarette lighter) into the socket. If the fuse doesn't blow with the other GPS plugged in, your GPS is faulty. This could mean a damaged cable or a bent pin in the plug causing a short when you plug it in.

Personally, I don't believe it is a damaged wire behind the dash. If the active wire was damaged and shorting behind the dash, it'd blow every time you put a fuse in. Since it's only happening when you plug something in, it is more likely to be either the device you're plugging in, or the fuse.

The CD player appears to be running off the same fuse. Does the fuse blow when you are using the CD player?

This is why I suggested a crossed wire, leading to a short = blown fuse.

A while ago my parkers and brake lights had crossed. Using my parkers turned on my brake lights too because they were both running off the parker fuse, but when I used my brakes they blew the normal brake light fuse and therefore didn't function on their own.

**GenesisEG** · 05-10-2010 07:09 PM

But a short on the supply side of the socket would blow the fuse each time it was replaced. It seems as though it's not blowing the fuse until something is plugged into it, which would suggest a problem on the load side of the socket.

I'm not an auto electrician (I'm an electrician/security technician), so please don't take my advice as gospel, but I have a hunch (based on previous stereo installs) that the cigarette lighter socket and the CD player run from the same source from factory. If this is the case, then it makes sense that blowing the socket fuse turns the CD player off also. However, I could be wrong. Without tracing the wiring, I couldn't tell you for sure, but my philosophy as a full time service technician is to eliminate the simple problems first. Cable tracing is a tiresome process, especially if the problem is hidden away under the dash or the carpet. Eliminating the simple and easy to test possibilities first might save alot of trouble, even if they are less likely to be the culprits. Fuse ratings and devices that can easily be disconnected from the circuit should be tested first. Once those have been eliminated as possibilities, then the more difficult possibilities should be explored. Fault finding is a process of elimination, start easy and work your way down.

Most of my input regarding electrical problems is based on generic circuit knowledge and a bit of logic. I have very little knowledge of the specifics of auto electrics, so please forgive any display of ignorance on my part.