Cigarette Lighter Help
youngsj
03-16-2007, 01:58 PM
Hello,
Neither of my cigarette lighters (front or rear) are working in my 97 Eldorado. I replace the fuse (20A), and it's fine until I connect the positive and negative wires to the cigarette lighter socket. Then the fuse blows, and that's the end of that. I have made sure there are no bare wires that could be exposed, causing a short. What may be causing this? What could be done to fix it? Also, I would appreciate knowing how these 12V sockets work. Is the metal screw protruding through the bottom of the socket ALWAYS in contact with the power wires, or does inserting something (such as a cellphone charger) into the socket push the screw complex down into the power wire? Thanks in advance for any advice.
Neither of my cigarette lighters (front or rear) are working in my 97 Eldorado. I replace the fuse (20A), and it's fine until I connect the positive and negative wires to the cigarette lighter socket. Then the fuse blows, and that's the end of that. I have made sure there are no bare wires that could be exposed, causing a short. What may be causing this? What could be done to fix it? Also, I would appreciate knowing how these 12V sockets work. Is the metal screw protruding through the bottom of the socket ALWAYS in contact with the power wires, or does inserting something (such as a cellphone charger) into the socket push the screw complex down into the power wire? Thanks in advance for any advice.
HeavyJ
03-17-2007, 12:06 AM
look at both lighter sockets, make sure there is not some foreign metal piece stuck in there making contact with the button in the bottom and the sides. have you unhooked the back one and tried a new fuse?
youngsj
03-18-2007, 07:45 PM
I have checked both lighter sockets for foreign metals, and none exist. I have unplugged the rear lighter, and the front lighter simply refuses to work...it doesn't blow a fuse, it seems there is simply no power in the wire.
HeavyJ
03-19-2007, 05:31 PM
from what wiring diagram I can find, you must have a lighter in the front and one in the rear console, they are wired in series. if you unplug the rear and are not getting power now to the front an not blowing fuses, there must be a ground in your wiring, probably under the console or carpet, could be the rear socket itself, but the only way to tell is to eliminate it or change it out.
youngsj
03-26-2007, 10:09 AM
The cigarette lighter circuit is now functioning, without blowing a fuse. However, only the rear lighter socket works. The front orange wire is "hot," but no power seems to be transferred up the screw as a cellphone charger doesn't work in the front. What may be the reason for the entire front socket to not be working, even though sufficient contact is being made, and the power wire is "hot?"
GreyGoose006
03-26-2007, 12:06 PM
and you know it is hot by testing it with a multimeter?
mazdatech177
03-26-2007, 02:10 PM
one or maybe both of your power sockets are shorted out. power to ground with no load. the load in this case being lighter element or your cell phone charger... get a new socket and plug it in and i bet your problem is gone
youngsj
03-26-2007, 03:29 PM
I haven't used a multimeter, but I have tested the positive wire of both front and back lighter with a simple circuit tester. They are both hot, as the bulb lights up on each. If I had a short circuit, the fuse would be blowing out, but this is no longer the case. I will try a new casing though. Any other suggestions would be greatly appreciated. Thanks.
ice745
04-12-2007, 10:42 PM
I have not seen the wiring diagram, but if both of these sockets were wired in series neither would work unless not only them both being hooked up, but both being used at the same time (i.e. depressed lighter or accessory plugged in both). The ground is probably direct to chassis, and the positive wire is probably shared between the two, making them parallel.
Right now it's the front that doesn't work? If you can remove it so you can access the wires, but don't disconnect the wires, plug an accessory in (cell charger). You said Positive was definitely hot. If charger is still not getting juice. Take a wire and wrap it around the shell of the socket (The outer casing should all be grounded, as long as you don't short it with the center positive pin this is safe. Now connect this wire you wound directly to the chassis somewhere. If it works then, you have a loose connection on the ground wire, or a broken ground wire.
Alternatively, you can disconnect the harness from the lighter, and test voltage of the contacts inside the harness with a DMM, a reading of +/- 12 will indicate both the ground and positive wires are good, 0 will indicate a problem. -12 volts will mean you just put the leads on the wrong order. If the harness is saying it's got voltage, then replacing the socket would be the easy way. Or you can find out why the voltage isn't transfering to the socket. I.E. is there an insulating material build up on the contacts of the socket (corrosion, dirt, etc...), or maybe the connections were overheated from shorting or excessive heat from the lighter and desoldered the contacts.
If you do try winding a wire on the outer part of the shell, and connecting it to the chassis, and that works, you can also just make that wire permanent. Just solder the end to the outer part of the shell, and connect the other end to a near-by bolt.
Right now it's the front that doesn't work? If you can remove it so you can access the wires, but don't disconnect the wires, plug an accessory in (cell charger). You said Positive was definitely hot. If charger is still not getting juice. Take a wire and wrap it around the shell of the socket (The outer casing should all be grounded, as long as you don't short it with the center positive pin this is safe. Now connect this wire you wound directly to the chassis somewhere. If it works then, you have a loose connection on the ground wire, or a broken ground wire.
Alternatively, you can disconnect the harness from the lighter, and test voltage of the contacts inside the harness with a DMM, a reading of +/- 12 will indicate both the ground and positive wires are good, 0 will indicate a problem. -12 volts will mean you just put the leads on the wrong order. If the harness is saying it's got voltage, then replacing the socket would be the easy way. Or you can find out why the voltage isn't transfering to the socket. I.E. is there an insulating material build up on the contacts of the socket (corrosion, dirt, etc...), or maybe the connections were overheated from shorting or excessive heat from the lighter and desoldered the contacts.
If you do try winding a wire on the outer part of the shell, and connecting it to the chassis, and that works, you can also just make that wire permanent. Just solder the end to the outer part of the shell, and connect the other end to a near-by bolt.
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