#13 fuse keeps blowing, no dash lights.

[Sho-Driver]

For quite some time now, I have been without dash lights. I originally checked the fuses and found nothing wrong. I rechecked today and found the #13, 5 ampere fuse burnt out. It will blow every time I turn on the head lights. Because I originally found nothing, I replaced the dimmer, headlight switch and relay.

I've tried to hunt down a grounded out wire, but I have not found anything yet.

To further elaborate into the story. I lost the dash lights while coming back from the store. They worked on the way there, then when I started the car to leave the store, they did not work. My aftermarket radio had been installed for quite sometime without any problems. I also have indiglo gauges, but they have been installed months before the dash lights went out.

If anyone knows any problem areas to check, help is appreciated.

TIA,

 

[NiNeTy Fo SHO]

The first thing I thought of when I saw the post was an aftermarket radio. I would check the wiring on the aftermarket radio....one usually doesnt use all of the wires. If one got loose and grounded it would take out a fuse.

About the same thing happened to a friend of mine....about 1-2 weeks after we installed the aftermarket deck, the fuse for the interior lights kept blowing. Upon further inspection, I forgot to tape up one of the wires coming from the dash that the radio didnt use.

 

[Sho-Driver]

I am utilizing all the wires for my after market radio. I had a Clarion installed for months before the problem occured. Since then, I have gone through the wires and installed a new Kenwood. With that said, I have a completely new harness on.

 

[wood_e]

Well you obviously have a ground fault somewhere. I would check your harness again.

 

[Sho-Driver]

Well you obviously have a ground fault somewhere. I would check your harness again.

Yes, I know this. That is why I was asking if there were any known problem areas. I would be out checking now, but I am at work now. Thanks for your help.

I've tried to hunt down a grounded out wire, but I have not found anything yet.

 

[wood_e]

I don't recall any areas of note that would be an issue. I would break out a multimeter and test wires. Maybe look around the chasis where the radio is. I know I blew a fuse on that when my dimmer switch wire wasn't capped off.

 

[Sho-Driver]

I don't think a multimeter would help at this point as I know I am not going to get any power after the fuse. Tomorrow morning I'll trace all the wires. I have no loose wires for the stereo system though.

 

[SHOZ123]

Use the ohm setting on the DVM and look for shorts. Ground one lead and probe the wire harness.

 

[Sho-Driver]

Good call, I could use a diode test.

 

[projectSHO89]

Good call, I could use a diode test.

Why? No point in doing so.

Just use the ohmmeter on the lowest setting. If your meter has an audible continuity feature, use that so you don't have to keep an eye directly on the meter. Just remember that the measured load under normal conditions won't be that much given that there are more than 1 dozen low-power bulbs in parallel.

It also helps if you identify the year of your car. There are significant differences between years and without the proper reference, only educated guesses can be made.

The Instrument Illumination circuit that feeds from F13 goes to every dash control that has a light bulb in it. Probably 10-12 devices, some with multiple bulbs.

I'd start by disconnecting the non-stock items first, then work my way through the other devices. if you can locate the relevent splice after the IP Dimming Rheostat, I'd take it apart and locate the relevent short circuit that way.

Steve

 

[Sho-Driver]

Why? No point in doing so.

Just use the ohmmeter on the lowest setting. If your meter has an audible continuity feature, use that so you don't have to keep an eye directly on the meter. Just remember that the measured load under normal conditions won't be that much given that there are more than 1 dozen low-power bulbs in parallel.

It also helps if you identify the year of your car. There are significant differences between years and without the proper reference, only educated guesses can be made.

The Instrument Illumination circuit that feeds from F13 goes to every dash control that has a light bulb in it. Probably 10-12 devices, some with multiple bulbs.

I'd start by disconnecting the non-stock items first, then work my way through the other devices. if you can locate the relevent splice after the IP Dimming Rheostat, I'd take it apart and locate the relevent short circuit that way.

Steve

Haha... You tell me there is no point in using the diode test, but then you tell me to use the ohm meter (and the diode tester). It serves the same purpose and is found in the same area as the ohm settings are on. A diode test only checks for continuity in a line. When it has continuity, it does not display a resistance value, it makes a beep to let you know you have continuity. Since I do not need to know the resistance of any given circuit, why should I bother with setting it on the lowest ohm setting?

With the diode tester, the common practice in eletronics would be using the 'half-split' method. By this I will purposely disconnect one end of the circuit I am testing, connect a lead to ground and the other to the circuit I presume faulty and work my way down line unit I find it.

Yes, I could have stated the year, but I know the problem, stated it and stated what fuse is burning up. At that point it is kind of redundant. It is a '92.

Thanks for the help.

 

[Sho-Driver]

Problem has been fixed. I could not physically locate the short, so I completely rewired the circuit. Everything works great now!!

 

[SHO--ripper]

Could you go into more detail about rewiring, my SHO is doing the same thing.

 

[Sho-Driver]

After following this schematic (figure 16), I was able to note that every light I lost was on the Lt Blue/red wire. Because it kept blowing the fuse, I was able to indicate that I obviously had a short. I spent a couple hours in attempt to locate the short, but because the dash limited my visability and ability to reach wires, I just rewired it. I figured I could waste another hour or two not locating the short, or just use that time to completely fix the problem.

At each component that is run off the wire in question, I cut and soldered in my own wire to the component. I started at the dimmer switch and ran wire to every component in parallel. This completely bypassed the short and now everything works as normal.