need help on fuses
#1
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Simply put I was putting air in my tires thru the Porsche inflator that sticks in the cigar lighter. After awahile the fuse blew (I was putting 60psi for storage.
No problem. pulled fuse 7 but when I tried to replace it with another the fuse blew the second it touched the entry point. I had another 15amp and tried again and it did the same thing. Everything else works, all fuses ok except I can't put a fuse into the #7 slot w/o it blowing it just as soon as I touch the entry point.
Any suggestions? Obviously the cigarette lighter doesn't work, but everything else does and #7 is just for the lighterr.
TIA,
Don
No problem. pulled fuse 7 but when I tried to replace it with another the fuse blew the second it touched the entry point. I had another 15amp and tried again and it did the same thing. Everything else works, all fuses ok except I can't put a fuse into the #7 slot w/o it blowing it just as soon as I touch the entry point.
Any suggestions? Obviously the cigarette lighter doesn't work, but everything else does and #7 is just for the lighterr.
TIA,
Don
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#2
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This is the time to have your multimeter out and touch either end of the fuse points to ground and measure them. One obviously should be hot and the other not. Pull out another fuse nearby and see which is the hot side for those fuses. Then figure out why you are obviously getting hot on both sides. I assume that you have looked inside the cigarette lighter for anything that could be grounding it out. If the 'extra' hot side comes from the cigarette lighter (which it must be process of elimination) there is some sort of short in that lighter that is introducing 12V into the system there. Is the lighter's quick slip on pole terminal where it should be? Has it fallen against and getting extra power from a light source in that area? Like from the fog light switch or om dash light?
#3
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obviously there's a current draw! is the inflator plugged in while you're putting in a new fuse? If not then theres a short to ground from the center hot side of the cigarette lighter to the surrounding case of the lighter which is at ground . i wouldn't put an ammeter across the fuse terminals as it will probably blow the internal meter fuse and depending on the fuse rating could potentially melt the 15amp rated wires plastic insulation going to the cigarette lighter.
Hope this helps
Bill
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Hope this helps
Bill
90C2
#4
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both the cigarette lighter and the lighter plug for the tire inflator work in the lighter socket in my other car (nonP). So in both cases the units themselves are ok.
That's as far as I've gotten so far.
To sum up: The lighter socket is dead and the minute I touch a new fuse to insert, it sparks visably and the fuse blows while still in my hand.
Also, I'm an electrical idiot
That's as far as I've gotten so far.
To sum up: The lighter socket is dead and the minute I touch a new fuse to insert, it sparks visably and the fuse blows while still in my hand.
Also, I'm an electrical idiot
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#5
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Without getting into the electrics I think the first thing you should do is take a visual of the inside of the lighter socket. Get a flahlight as it's dark in there. I'm relying on my memory cause my car isn't with me, but if I remember correctly there are 2 metal tabs that kinda grab the cigarette lighter's element on the outer edge. These tabs have been known to bend and if they make contact with the center conductor of the cigarette lighter element contact, that's your short. Get in there with your needle nose plyers and bend the tabs back into position so that they don't make contact witht the center conductor contact in the socket. If you have 2 cigarette lighter sockets compare the working one to the broken one. Don't worry about shorting anything out when you use the plyers as the fuse is blown and there is no power in there. Thers's also a light inside the lighter socket and I'm not sure but I think it's part of the instrument backlight circuit when the hedlights are turned on if not then it's probably part of the lighter circuit. Does it illuminate when the headlights are turned on?
Hope this helps
Bill 90C2
Hope this helps
Bill 90C2
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OK, so this thread is a couple of years old, but my problem is similar in nature. My cigarette lighter has never worked since I bought the car last October. My fog lights have worked. I was driving home the other night in heavy fog and realized my fog lights were not working. Checked the fuses. Fog light fuse was blown, so I replaced it. They still don't work. Decided to check the cigarette lighter fuse too. It was blown as well and, like Don mentioned above, as soon as I touch the fuse to the connectors, it blows (sparks and all).
I hate to drive it at night w/o fog lights and I would really love to be able to inflate my spare if it came to that.
Any thoughts would be appreciated,
Matt
I hate to drive it at night w/o fog lights and I would really love to be able to inflate my spare if it came to that.
Any thoughts would be appreciated,
Matt
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#8
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Its easy for the plug to come off the lighter if the radio or CCU is taken out. Maybe that happened and it is shorting some how at the connector. Its not a fun job hooking it back on.
#9
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The cigarette lighter was busted since I bought it, so no telling.
The fog lights, on the other hand, that was the first thing I fixed on the car. I had a busted lens. I replaced it and the fog lights worked fine. No clue what could have changed in 2000 miles and 2 months in the garage.
The fog lights, on the other hand, that was the first thing I fixed on the car. I had a busted lens. I replaced it and the fog lights worked fine. No clue what could have changed in 2000 miles and 2 months in the garage.
#10
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I looked at a car for a guy .
He parked it in his garage ,
went to drive it and it would not run .
A small animal had eaten the insulation off of many wires .
He parked it in his garage ,
went to drive it and it would not run .
A small animal had eaten the insulation off of many wires .
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My guess is the wires to the lighter plug overheated and melted through the insulation. They are now touching in a dead short. Get a look behind the socket - if you see any sign of insulation melt, you found the problem. Sometimes wires are bundled together, and the fault is in the middle of the bundle and difficult to find. If there is a big bundle, the fix is to splice a wire section around the bundle to restore electrical feed to the lighter.
Next time you need 60 psi, it is best to go to the filling station. That 12 V compressor is for roadside emergencies.
Next time you need 60 psi, it is best to go to the filling station. That 12 V compressor is for roadside emergencies.