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DH sent me out to do some work on the cars this afternoon. He was sidelined by a stomach bug so I was happy to get out of the house - yuck - :eek: My car needed another oil change and his needed just one simple task....

All I had to do was pull the center console, disconnect some wires, put it back together, and done. EZ right?

As soon as I sat down in the car I got antsy and called DH from the driveway to ask if I needed to disconnect the car battery. Here's the never listen to your spouse part he assured me that nothing I was doing would expose hot wires and that I didn't need to worry. I should have listened to my intuition :jester:.

So I pull the shift boot, unscrew some screws around the console and start levering it out. As my luck would have it, a penny fell out of the ashtray and square into the cigarette lighter. SPARK

I slunk back into the house and fessed up to the hubby. :cursing: He was PISSED until he googled 'penny cigarette lighter' and got 300,000+ hits.

I pulled the negative on the battery, disconnected the wires to the cig lighter and used some bamboo to fish the UNLUCKY penny out.



You can see the burn mark on the penny where it arc'd. I figured as much and pulled the blown cig lighter fuse which also shows arc'ing on the blade.

Now, here comes the unlucky part :wallbash: even after checking EVERY SINGLE FUSE IN THE DURN CAR the power windows/lock/trunk release/windshield wipers/ and top no longer work. Despite the valiant little fuse doing it's job I still managed to fry something electrical in the car (seems like it must be one of the control modules) :cry: :cry: :cry:

Thankfully, the car will still run and can function without the suspected module. So, it won't be out of commission while were waiting for a replacement. (And I sure hope it's that module and not some other problem I'm going to have to hunt down in the 20,000 miles of wiring in the car.)

But, heavens-to-betsy, I KNOW better than to work HOT. I hereby tender my resignation of all my awesomeness credentials. I will now go sit in the corner for the rest of the weekend :dunce: and think about what I did.
:censored::censored:
 

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I would not have expected the penny cigarette lighter incident to put all kinds of other things out of commission.

It's a different circuit. (Or is it; check the car owners manual. But if you replace the fuse and the cigarette lighter is working again then anything else on the same circuit should be working again.)

If you accidentally shorted out a receptacle in the bedroom you would not expect the furnace and refrigerator and doorbell circuits to all go out of commission.

One hint: Car circuits are grouped; one major group is things that work when the ignition is off; another group is things that work only when the ignition is on. This may narrow down on what wires could have been fried.
 

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Can't quite figure what your original mission was.Tear open consule,disconnect wires, reconnect? Your dh sounds like a Goof. Then he squacks at you???
 

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Don't put the lighter back in but replace the fuse and see if everything works, leave the lighter out and replace it if itself shorted.

Bottom line, lighter itself shorted out or the part where you plug the lighter in shorted out.
 

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Discussion Starter #5
bobelectric said:
Can't quite figure what your original mission was.Tear open consule,disconnect wires, reconnect? Your dh sounds like a Goof. Then he squacks at you???
Ok. It's slightly convoluted.

So DH installed a oem module that is not available in USA delivered versions of his retractable cabrio e45 M3. it allowed remote operation of the top. Worked great for a year then got unreliable. My mission was to unplug the thing and remove it.

Here's were things tie together. The Remote top mod was connected to: both wires to the cig lighter, two wires in a secondary wiring harness, AND two wires to the suspected failed GM5 module.

the short to the cig lighter Definitely had a path to the GM5 module. The only problem is, there isn't visible damage to the circuit board. But I havent pried open all the relays yet.

STUPID PENNY

And unlike many cars (including my other ones), the durn BMW's cig lighter is 'hot' when the ignition is off :cursing:
 

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I dont do much electrical work on bmw's, but on many cars they will group fuses into subsystems. Example: five 10-amp circuits on the interior panel will be fed by one 50-amp Maxi-fuse in the engine compartment fuse panel. They used to love to use fusible links too (lengths of gray wire that act as a fuse).
Sorry to hear about the penny problem. Has happened in my Grand Marquis more times than I can count in the last 7 years. I keep a box of fuses in the glove box now.
 

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Discussion Starter #7
Marqed97 said:
I dont do much electrical work on bmw's, but on many cars they will group fuses into subsystems. Example: five 10-amp circuits on the interior panel will be fed by one 50-amp Maxi-fuse in the engine compartment fuse panel. They used to love to use fusible links too (lengths of gray wire that act as a fuse).
Sorry to hear about the penny problem. Has happened in my Grand Marquis more times than I can count in the last 7 years. I keep a box of fuses in the glove box now.
Marqued97- thanks. DH swears there are not fuses in the engine compartment (my Ford and our Subie have them). Fuse '47' was the culprit, but something has definitely killed the trunk release. But I can't find a fuse for that system. This tells me I haven't found all the fuses.

Sheesh. Durn penny.
 

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Did replacing the fuse restore power to the 12 accessory plug (cig lighter)? What if the inoperative devices are paralleled off the same circuit and a common point got cooked a little?
 

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What year is it, out of curiosity? There very well might not be a fuse box under the hood, but I'm willing to bet there's another distribution box somewhere in the car...especially what with all the options available. I had a focus recently that had shorted out parking lights. The guy started putting 30a fuses in a 10a spot. Melted the buss bar IN the fusebox past that point, knocking out the next 4 fuses down the line. Also melted 17' of harness to the rear of the car. That was a fun repair ;-)
 

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Only if you attempt to remove the positive cable before the grounded cable and your wrench contacts the framework.:eek:
Had that happen with a buddy working on a bank of Exide batteries for the ship telephone system. Amazing how he was able to not kill himself, with the amperage.
 

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Discussion Starter #14
a7ecorsair said:
Did replacing the fuse restore power to the 12 accessory plug (cig lighter)? What if the inoperative devices are paralleled off the same circuit and a common point got cooked a little?
Good question. Ill have and answer next week. And yes, I done BBQ'd something.
 

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Discussion Starter #15
a7ecorsair said:
Only if you attempt to remove the positive cable before the grounded cable and your wrench contacts the framework.:eek:
And then you lose a wrench but gain a handle ;)
 

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Had that happen with a buddy working on a bank of Exide batteries for the ship telephone system. Amazing how he was able to not kill himself, with the amperage.
Lots of amperes don't kill. Enough voltage to get through your body depending on the circumstances (how moist your fingers are, whether the path such as from one hand to the other passes near your heart, etc.) and about one tenth of an ampere are enough.
 

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It does, when you are working on a DC battery bank that has over 400 amps, and about 30 48vdc batteries in the bank. He was not the first to do it, and lucky there was rubber mat on the false floor panels in the battery room on our ship. There is a few more I can tell you about him, such as trying to flood the Pit-sword trunk, etc. Was not the brightest sailor in the fleet, even though he scored high on his ASVAB, and other tests as a Interior Communications Tech.
 

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Leah, many cars have fusible links installed as an extra layer of protection. You probably blew one of those.

THEY are not so easy to fix. They are part of the permanent wiring harness, and have to be cut out and spliced back in to restore power to your inoperative circuits.

You may want to stop by over at PASCO tomorrow and have them check it out.
 

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Discussion Starter #19
Thanks Sparks - I hadn't thought of talking to the PASCO. we've got one just around the corner.

I'm pretty sure my husband isn't going to let me get anywhere near troubleshooting this..... At least not with any loose change in my pocket ;)
 

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Thanks Sparks - I hadn't thought of talking to the PASCO. we've got one just around the corner.

I'm pretty sure my husband isn't going to let me get anywhere near troubleshooting this..... At least not with any loose change in my pocket ;)
Wait, wasn't it his loose change that got you into this pickle:whistling2:
 
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