Wiring A Cigarete Lighter From Scratch

[JiP]

Hey guys, I feel like a noob for asking such a simple thing but after all my work it no workskis.

 

The car in question is my Subaru. Warranty refuses to cover repairs so they told me I have to see an auto electrician. I don't have the $300 I was quoted so i decided to do it myself.

 

I've probed a few mates to find out what is needed and gone ahead and installed it directly to my battery from the boot/cargo area. That one will be used for camping.

 

Anyway my mate told me to run 4mm wire, while another told me to run a 15A fuse. I've plugged it all in and... NOTHING

 

This access panel is for one of the tail lights.

I've run the one that come directly out of the back to the fuse, then battery. I one off to the side has been connected to a bolt that secures the tail light.

 

Now does it matter that the fuse holder I bought came with a 30A fuse? I think the wire is a thicker grade too. They only had that one and a real thin one with a 10A fuse.

that 30A holder should be able to take a 15A fuse? I didn't have a new one on hand so I took it out of my hardtop. It was in good nick but I didn't check it again after I tried my ph charger.

 

Please let me know what I've missed.

 

thanks,

J.

[phat_20]

You've got the positive and negative wired the right way :)

 

I would say check the bolt where you earthed it to see if its making a good connection to ground (metal chassis).

 

Have you got a test light? its a cheap tool ($5-$10) to check if there is power at the fuse and positive tip of the cigi lighter. Then you can determine whats missing.

[kiahn]

check what size fuse subaru has used on all their other cigarete lighters, and use the same

make sure there is a perfect ground positive,

its really just 2 wires so not much can go wrong

[jono1986]

likr kiahn said it's only 2 wires so not much could go wrong, Positive should go on the back of the plug and and negative on the side, which you've done. If you have a multimeter check the resistance of the earth from the socket to another earth stud somewhere (not the one you used for the plug itself). Also check the resistance of the fuse by pushing the probes into each wire coming out of it, but don't have anything plugged in to the socket otherwise you can damage the meter. if you don't have a multi meter you can get real cheap ones from dicksmith or jaycar, And it doesn't matter what size fuse you put it the holder just as long as there the same type (Blade type or other), but obviously not too bigger fuse otherwise you'll melt the wiring a 15A or 20A should do.

[Medicine_Man]

Fuse should be right near the battery supply, Fuse size is dependant on the load that you will have on the circuit..

[Jono]

Fuse size is dependant on the load that you will have on the circuit..

 

...and as long as it is less than the current carrying capacity of the wire its protecting, or else the wiring will get very hot and melt the insulation before the fuse burns out.

[Toy-Yoda[RL]]

...and as long as it is less than the current carrying capacity of the wire its protecting, or else the wiring will get very hot and melt the insulation before the fuse burns out.

Which for the record is an awesome way to start an electrical fire.......

 

And those aren't fun to clean up after, let alone fix.

[Medicine_Man]

No shit, I'm a f@$king auto electrician for f@$k sake, Do you think I would honestly be that f@$king stupid to not select the right wire before wiring something up.. The reason why I said its dependant on the load, You are not going to put a 5A fuse in there and pop it the first time you plug something in.. Cable has to be selected to minimise voltage drop and carry the correct current load. You are not going use 4mm cable to wire your starter motor up now are you?

 

It is very important to have the fuse right at the battery, I made this a point because of reading the following

 

"I've run the one that come directly out of the back to the fuse, then battery. I one off to the side has been connected to a bolt that secures the tail light. "

 

Fuses are designed to blow in the event of a dead short, Say the wiring rubs through somewhere and touches the frame of the vehicle. No point in having the fuse right at the socket when you still have all this wire running along the vehicle back to the battery.

[Evan G]

^ this bloke knows his shit :)

[kiahn]

yeh, like medicine man said, you wouldnt use 0 gauge wire for an led light

so pick your wire correctly, there is an algorithim to decide what wire but i can't remember it

also if you use the same size fuse as subaru has then you shouldn't have a problem with it, unless you only want to use more than 1 appliance on the wire in which case you will need to calculate how much you will need.

[JiP]

Thanks for the advice guys. I just quickly went out to do some trouble shooting.

 

I undid the tail light nut and put it back on just in case it wasn't connected right. I checked to see if it worked and still nothing.

So I went to check the fuse, pulled it out, it looked fine. So I popped it back in and went to check again if it was working and YES!!!

 

So I'm all set for the camping trip :) Thanks heaps!!

 

I'll figure out where to install the new front one at a later stage.

Edited November 8, 2009 by JiP