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tippycanoe2
01-15-2007, 09:55 PM
Image - Fuse Panel 1 (http://img211.imageshack.us/img211/2939/fusepanel1py0.jpg)
Image - Fuse Panel 2 (http://img109.imageshack.us/img109/9010/fusepanel2uf8.jpg)

I was driving around about a month ago and my dash lights went out. I found the bad fuse in the dark by feel and replaced it. Everything looked good and the dash lights worked again.About 2 weeks later, I noticed the dash lights flickering when I went over bumps. I pulled over in the dark, reseated the fuse by touch, and started driving again. No problems after this.

Last night, the dash lights went out again. When I got home, I looked under the dash and the fuse panel around the fuse had melted! I pulled the fuse and examined it. It was a bit melted on one side, but not blown. I could get the lights to work by pushing the same fuse against the contacts, but obviously the socket would not hold the fuse after being melted.

I started searching online and found (from several sources) that if a fuse is seated but not making good contact, there can be arcing around the contact point, which generates a lot of heat. This is what happened to me. Do NOT jam fuses into their sockets in the dark!

I am thinking about trying to solder a line fuse between the contacts, but it is a VERY awkward place to work. I am also worried that the heat from the iron will melt the surrounding plastic.

Anyone have any ideas for fixing this, short of replacing the entire fuse panel?

evolution
01-15-2007, 10:27 PM
if it were me, i'd check the circuit and make sure things look okay before attempting to wire in another fuse. (ie. check all the wire insulation, and make sure there is no excess resistance on the wiring)

then again if it were me, i'd pick one up from a scrap yard and replace the whole assembly.

if you do go the route of wiring a line fuse, it would be safer (and i use that term loosely) to cut the wires leading to the fuse, and splice it in there- rather than doing it from the socket side

GT4SOM
01-16-2007, 01:08 AM
I would pull the fuses and inspect make sure its not being grounded some how. Thats pretty weird how it would burn up like that and not pop the fuse. Definately inspect the circuit.

tippycanoe2
01-17-2007, 08:06 AM
if you do go the route of wiring a line fuse, it would be safer (and i use that term loosely) to cut the wires leading to the fuse, and splice it in there- rather than doing it from the socket side

You are 100% right about that. I will try it tomorrow.

RedWing
01-17-2007, 02:46 PM
tippy canoe & tyler ,too???

I havent heard that 4 a good while. (lol)

1. Disconnect pos. batt. terminal.

Cut wires away from burnt out fuse holder; but only the wires that go 2 that 1 particular fuse holder.
You may find that the fuse panel uses a common positive buss or printed
circuit 2 supply 12vdc to all the fuses and only the individual circuits have wires connected to 1 side of all the fuses.

I would not worry about melting the fuse panel block with the soldering iron
so long as you are using a 10 to 60 watt iron , you have little 2 worry about.
A transformer type quick heat 200 to 300 watt soldering gun is ok to use too.

Just dont go in there with a soldering tip on the end of a propaine tourch
because that will melt & burn stuff real quick.

With the power off, check circuit with ohmmeter to see that it has some resistance, 10-20 ohms, not a dead short to ground, 0 ohms.

Install in line fuse holder with same amp fuse you had b4.

After reassembly--because I am sure you will need to unbolt the fuse panel
to work on the wire connections behind it; you should check the current flow
in the wires to make sure that it is at a reasonable level with regards to the fuse current rating.

Checking the current draw with the circuit "on" is not absolutely necessary,
if you dont have a dc current meter in the proper amperage range.

If the new fuse does not blow or get hot, this is an indication that your instrument light citcuit is ok and the problem was caused by weak or
overheated prongs in fuse box .

Cause: Prongs that make connection to fuse get bent from jamming fuse into
socket or they may have been previously weaked so that that do not make a good tension (squeeze tightly) mechanical connection.

Without a tight squeeze in the fuse prongs, a high resistance connection develops, and power in watts, is dropped across this acidently made resistor,
which promply heats up, starts oxidizing, thus making even more resistance and developing more heat , and you took pics of the result.

Next 2 lastly, when you get fuse panel unbolted ,u may find all printed circuits and no wires , back there. You can still connect a wire to the positive feed wire of the fuse box and trace the printed circuit from the fuse to the terminal and wire that plugs into that black wire cluster I seem in your pics. Use the ohm meter, with batt disconnected, to make sure you traced the proper wire.

Dont have an ohmmeter, use $4.oo continuity tester instead.

Better to buy youself an vom (volt-ohm meter). Learn 2 use it by reading
instruction book it comes with. Vom I constantly use, every couple of weeks,
4 rest of my life. Only cost $10 -cheap20.oo better--30.oo way better or
40.oo top drawer. I usually buy way better or best.

If all else fails, get used fuse panel at junk yard. But remember,junk yard
panel could have weak or rusty sockets too. If sockets look rusty--take out fuses and inspect with flashlight, get another fuse panel.

If you must use a rusty fuse panel, be aware you need to lub the contacts with wd 40 and grease , and will have oxidation problems leading to high resistance contacts & more burn outs. Tell the junk man the contacts are rusty and offer him 1/4 price or less if you really cant find a good one.

alltracman78
01-18-2007, 01:43 AM
Actually, this is perfectly normal and your circut is probably fine.

It is caused by a weak "leaf" in the fusebox.
Or one that got bent back.

The fuse didnt' blow because amps blow fuses.

That bad connection raised the total resistance in the circut, actually lowering the amperage flowing through it.

The other thing the bad connection did [and this is why it's burnt and melted] is to create another load in the circut. A load uses up voltage. Which creates heat.

So, the extra load had no work to do other than create heat and melt your fusebox.

Now, there are 3 ways to fix this.

The easiest, but worst way, is to buy an inline fuse, get 2 larger [than the fuse connectors] male spade conectors, connect the 2 spade connectors to the 2 ends of the fuse wires, and and simply force the larger connectors into the holes.

Next you can wire in a inline fuse to the actual wires, but this probably requires you removing the fusebox anyways [I don't remember exactly where these particular wires route], which leads us to solution 3

Replace the fusebox. :)
It's not quite as hard as you think.

The worst part is removing the top inner connectors.