Question about electrical wiring

[ky0u]

If i wanted to add another cigarette lighter to my car, would splicing the additional wiring to the original lighter wiring be the correct means to do so or would that cause one to leech power from the other? If so, what would be the correct way to wire this

[Vittor Monti]

Electrical MOTOR or APPARATUS trouble shooting, electric motors, electrical problems, Repair of most any electrical/mechanical/electronic apparatus, OEM, AC, DC, Industrial Applications, Three phase, single phase failure mode.

[StereoInstaller1]

If i wanted to add another cigarette lighter to my car, would splicing the additional wiring to the original lighter wiring be the correct means to do so or would that cause one to leech power from the other? If so, what would be the correct way to wire this

You smoke enough to need a second lighter socket? Damn, thats worse than me!

[TobyB]

Depends.

If you wanna run 2 lighters at once, no, you'll pop fuses.

If you wanna charge 2 iphones, sure, that will do the deal just fine.

See where I'm headed, here? If the 2 devices draw less than the lighter
you'll be fine.

t

[ky0u]

Depends.

If you wanna run 2 lighters at once, no, you'll pop fuses.

If you wanna charge 2 iphones, sure, that will do the deal just fine.

See where I'm headed, here? If the 2 devices draw less than the lighter
you'll be fine.

t

Gotcha. That was the reason I wanted another socket. Power sources

[jalopi]

It sounds like you want to wire it up in parallel (each lighter/12v outlet has the same power wire) as opposed to in series (power from one lighter/outlet comes from the other lighter/outlet).

Wiring it up in parallel is the right way to do it. Look up a schematic and see if there's anything else on the circuit. If not, bumping up the fuse size should prevent them from blowing out.... typically switching to a bigger fuse isn't advised (since you've typically got a mystery issue / potential fire hazard) but for your application it'd probably be OK. Just grab a hold of the power/ground wire after whatever you're running has been going for a few minutes and make sure the wires aren't getting hot. If they're not, you should be good.

[bmwman91]

If you want to add a second one, the RIGHT way to do it is to run new wire to the 12V terminal block on the firewall and a new ground. The BIG terminal block, not the smaller one above it that is dedicated to the ECU and injection electronics only. Find out what gauge the stock wires are (should say in wiring diagrams) and use the same or heavier gauge. You also MUST install an insulated inline fuse on the new +12V wire as close to that terminal block as possible, and I suggest using the same type and current rating fuse as the stock one for the stock lighter outlet.


The stock wires are sized based on the existing fuse, and putting in a bigger fuse is never the answer. Yes yes, risk of fire is low, but if you have ever seen a car fire, you know that it spreads so fast that you will be lucky to have time to stop the vehicle and get out without serious injury.

[AndrewBird]

Yeah, swapping in a bigger fuse is a BIG no. The wiring con only handle so much current and the fuse is rated correctly to pop before the wiring gets too hot.

Why not just get one of these:



Or even better, get one of these:


They plug into where the glove box flashlight is and gives you a 12V outlet in the glove box.

[jalopi]

FYI - took a peek at the schematic for the "cigar" lighter (I guess that's what typical BMW owners used it for in the 80's?). Looks like the 12V outlet has the circuit to itself and is protected by a 30 amp fuse using 12 gauge wire (good for about 35ish amps @ 4-6 feet). That glovebox outlet converter thing is pretty cool, but keep in mind that the circuit is only good for 7.5 amps and rocking a mix of 16-20 gauge wire.

But yeah, I don't think running a few ipods/pads/phones and a gps or whatever'll be a problem with what you're planning.

[ky0u]

Yeah, swapping in a bigger fuse is a BIG no. The wiring con only handle so much current and the fuse is rated correctly to pop before the wiring gets too hot.

Why not just get one of these:



Or even better, get one of these:


They plug into where the glove box flashlight is and gives you a 12V outlet in the glove box.

Because I'm trying to integrate it into the car without making it look like an add on. I wanted to mount the secondary lighter to the rear ash tray in my car, that way it's all clean inside

Thanks for all the info guys, really helps a ton! I'll do some reading into it myself. Electrical fire is the last thing I want

[TobyB]

Just do it. Use 12ga. wire, protect it well, get it a nice 12ga. ground and you'll be just fine.
And if you never plan on spliffing up a big stogie with it, swap to a 15a fuse for extra
peace of mind.

Seriously.

t