All the sudden a coulple weeks ago my fuse blew for my cigarette lighter on the dash. One of the two on the dash I use to power my Sirius radio the other is occassionally used to run apower inverter and rarely use the actual lighter. Anyway what might cause this fuse to blow? I first realized the fuse blew after usin a coffee grinder with the power inverter in case it makes a difference. Thanks for any n all suggestions.
The fuse is probably working as designed, and opening due to a short or over current condition.
If the fuse only blows with something plugged in, that something may be drawing too much current.
If the fuse is blowing with nothing plugged in, I'd inspect wiring for chaffed, pinched, or melted wire/insulation.
Take a look at the fuse after it opens up. If the wire inside looks like it just melted, that is the indication of an over current that wasn't massive. Just drawing too much current from the circuit.
If the fuse wire looks like it exploded, that is indication of a massive overload or a short circuit.
If it is the first, the inverter is drawing too much current when the grinder starts up. If the second one, then there is a wiring fault someplace and I would find it and fix it before I put another fuse in there.
Inverter is never left plugged in and is only used on occasion. Well the fuse I replaced had some black residue on the inside edge of the plastic casing from when it blew and did look "broke" rather than melted wire from what I recall. I hope this isnt a major problem. How would I go about finding and fixing the fault? Do I take the dash apart, find the wires going to the lighter outlet and follow to the firewall then if not found continue under the hood from firewall to the fusebox?
You will have to start inspecting the wires at the back of the lighter socket. Is the fuse under the hood or in the cab? Follow the wires from the lighter socket to the fuse block and if it is a wiring fault it will be between the lighter socket and the fuse block.
Didn't you say that you are running your Sirius radio on this circuit? Is it possible that this is where the wiring fault could be? Maybe the place where the radio taps into the power line isn't insulated well enough and it is causing the problem when it makes contact.
the fuse is under the hood. Yes iam runnin my Sirius through the cigarrette lighter on the driverside of the dash. the dock is mounted on the dash and left plugged in at all times but I usually remove the radio nightly. There is a second cigarrette lighter (power outlet) closer to the passenger side which Ive used the inverter in. What exactly do you mean by it not being insulated well enough? How would I fix this it is the case? Thanks for the help
Odds are that the overload (perceived) when using the inverter has melted the yellow and black wire together within 6 inches of the suspect outlet, or it has actually melted the outlet internally...
The outlets in the dash are on two different circuits, and, therefore two different fuses.
Cliff's notes:
Sustaining a near 20 amp draw on any GM in-dash outlet will overheat and melt the wiring insulation before finally blowing the fuse. Fortunately, the melting almost always occurs within 6 inches of the outlet.
well thanks mccall, I dont have time to look just yet but I hope your right. But why was I able to use it still after replacing the fuse the first time? If the wires were melted like you say would it still work with a new fuse installed? Also I can only find one fuse labeled for the cig lighter, if there is a second for the driversside outlet which one is it?
I suspect you are simply overloading the circuit with the inverter. Even if it's fused at 20 amps it will only handle 240 watts. Since your inverter isn't 100% efficient that's probably only about 190 watts output. How many watts does your grinder pull? I bet it's well over 190.
so from post # 14 in that thread I can assume they are both under the hood then, as the 1 labelled cig lighter is farther down than the second row from the firewall. Ill have to check that later today thanks for the help. But another question yet. If both fuses are bad and I replace them, and the wires are burnt somewhere, will I be doing any further serious damage to anything?
If these wires were overloaded, some insulation may have melted or degraded. If you continue to use this circuit MAYBE nothing will happen as long as you don't overload it again, BUT I wouldn't chance it. If the insulation melted enough that bare wired shorted to ground, the fuse should open trying to protect wiring and prevent possible fire.
When you pop the fuse box and look on the back it says both are 20amp on mine. I replaced the fuse earlier but wont be using the inverter anymore but I suppose I should check the wiring when I get a chance. Can I just tape it up with electrical tape or should it be spliced
Depends on the look. If burned bad then possible the braids of wire have melted apart on some so will not handle the maximum power the gauge of wire was intended for. But if looks ok then electrical tape and then put a small tie wrap around it so it does not start coming off over time.
I tore my dash apart a month or 2 ago, had to take the glove box and everything right out , stupid , looked at the wiring coming from the cig lighter port (the one on the passenger side) since that is the only one giving me trouble. Could not find any obvious problems with the wiring. Nothing looks burnt or cracked casing or anything it all looked good that I could see , but I couldnt see much as the wires seem to go toward the firewall and Im assuming to the fuse box under the hood. So I replaced the fuse again finaly and tested the cig lighter and it worked but popped the fuse again. So I replaced the fuse and tested it again , and the lighter worked and the fuse didnt pop its still good. Tried one more time and still working , fuse is still good.
After going through this process Im not all that knowledgable with wiring and stuff but I think , (and correct me if im wrong) , its safe to assume that there is a bare wire somewhere in there causing it to short out and blow the fuse , yet not all the time. Hmm , this sucks I dont want to have to replace the fuse anytime it keeps blowing and I couldnt find the problem wire myself. WTF. Any suggestions where to go from here? Im considering bringing to a shop to have the problem fixed just for peace of mind because I really dont use the cig lighter very often at all but still like everything to work as it should. If I do end up going the shop route it wont be for quite awhile because ive got a lift that ill proly have installed somewhere if it gets cold before I get a chance to do it and same for my pump rub T-case kit.
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