cigarette lighter wiring

[nwymbs]

Hi All -

I finallly tracked down a used cigarette lighter and was excited to get the dash all that more complete and stock. I stared at the wiring diagram and thought one wire to the dash light switch and another to the red wire terminal of the headlight switch was correct. As well as a ground to the bottom dash crossmember. Well, as soon as I connected the battery my dash went up in smoke! Luckily the only thing toasted was the line going from the headlight switch to the cig lighter. Rather than pressing my luck any further has anyone had success with wiring one up? I realize that there may be something amiss with my wiring elsewhere that is causing this but I doubt it should be this bad!

Thanks
Nick

[nwymbs]

ok, so I think the case may be that I need a resistor that is inline with the main red power wire that connects up with the light switch in the dash. anyone know the specs on this? is it the same as that on the heater motor?

thanks
nick

[papajam]

The only resistor that I'm aware of is for the oil temp gauge on Giulietta models. What year and model Alfa are you working on?

[nwymbs]

it's a '63 giulia spider...

[wolfbobpalm]

Are you sure the used cig lighter you have is not shorting out? Run 12 volts to it on the bench to see if it may be the problem. I have a '62 Giulia spider and I know of no resistor going into the lighter.

Brent

[nwymbs]

that I'm not sure of so it could be the case....

is it possible for a short to completely toast the power wire that runs to it?

[wolfbobpalm]

It depends on the gauge of the wire; but yes it could.

[pathung]

I have a '63 Spider under restoration, and don't think that it had a resistor for the cigarette lighter when I tore it down. In the attached picture, the black wires simply headed to the fuse block and wherever else it's supposed to go (ground, I suppose). Good luck!

[nwymbs]

pathung, thanks for the pic!

it looks like there are no direct connections to the adjacent light switch. this might be where I'm going wrong, but when you look at the wiring diagram clearly one runs to the headlight switch and the other to the instrument switch. hmmmm.....

[pathung]

Interestingly, the diagram that Lionel Velez (from whom I bought the harness) provided for me does not show a cigarette lighter as one of the accessories, while my car comes with one. This is something that I'll need to investigate - my car was originally sold to Frankfurt, a Euro-spec car with side-markers; not sure if this has anything to do with the absence/presence of cigarette lighter/wiring depiction. Is your car a U.S. car?

The wire that you're referring to, connecting the accessories, I don't have such. The wires for all my switches mostly go to the component that they operate, as well as the fuse block, ultimately. The wiper switch, however, has one wire going to the wiper motor, and the other grounding locally, that's it.

[nwymbs]

I have a 63 that was originally sold in new york and it did come with a lighter.

If you have a copy of the manual (or car disc) it clearly shows a label for a lighter. From the photo, it appears that we have the same lighter. So I think I'll try out running a wire straight from the fuse block and see what happens....

[pathung]

A few more photos of my lighter; it may have been installed at a dealer after it was privately imported into the U.S.

[papajam]

The Giulia Spider wiring diagram I have also shows the lighter being powered with a 10ga red wire from the headlight switch (daisy-chained). This does not necessarily mean though that the wire, in the physical sense, jumps directly from the headlight switch to the lighter. It could go back into the harness and emerge in another location. The instrument light switch however is powered by fuse #4.
The lighter requires only two connections; power and ground. If you have a direct short circuit with the lighter hooked up, then, as Brent said, the problem is in the lighter.