[horvath]

I just got a new chrome dome light for my truck and I'm trying to figure out how to activate a ground wire from my door switches so that when I open the door the dome light comes on with my floor lights.

The dome light has ONE wire (for the positive wire) that goes to one side of a toggle switch in the dome assembly, then it comes out the other side of the toggle switch and goes to the bulb. Naturally, when I throw the switch the ground from the dome assembly-body activates the light.

I have a ground wire that goes to my door switches, but I can't figure out WHERE to put it so that the light will get grounded and turn on when I open the door.

Help?

Alan
54 Chevy Pickup

[galaxieguy3]

You could either attach a ground somehow to the socket or metal socket bracket, IF you can insulate the socket from grounding to the truck when it is mounted.

A second way would be to ground the lamp to the truck and run the power wire through a relay, using the door jamb ground switch to activate the relay.

[horvath]

Thanks.

I was thinking if I found the ground post on the socket and connected the ground wire from the door switch there, I'd be in business.

Alan
54 Chevy Pickup

[willys36@aol.com]

Slick solution would be to use one of your famous relays and have the door grouding switch run the relay coil which in turn feeds +12V to the light.

[horvath]

Thanks, Willys36

I need to do something like that because the dome light switch is turning the positive 12 volt feed on and off ... i.e. I can NOT operate the light by turning the ground on/off.

Since the switch on the dome light breaks the 12v positive, I'd have to have two 12v feeds going to the bulb -- right? One that (already in place) goes through the dome's on/off switch, and one (to be added) from the relay. That way, one turns the dome on when I open my doors and the other turns the dome on when I use the dome-switch. Yes?

But I don't understand how to wire up the relay! Can you explain how I would wire the relay from the door switches to the dome light?

Alan
54 Chevy Pickup

[horvath]

HA! Thanks to Mark Hamilton at Mad Electrical, I now know how to make my dome light happen with the door switches using a relay.

On the relay:
#87 feeds power to the dome light
#86 gets spliced into the wire from #30
#30 goes to the power source with a fuse
#85 goes to the door switches

Thanks for pointing me in the right direction, my friends!

Alan
54 Chevy Pickup