Switched power source under the hood?

[dwoloz]

I am in need of an ignition switched 12v supply under the hood on my 83 w123
Any good ideas?

Thanks in advance,
Dan

[bustedbenz]

The first thing that comes to mind is your windshield washer system. It doesn't work unless the ignition is on. Whether the ignition only disconnects the turn signal/wiper stalk from inside or if it shuts the power to that pump, I don't know.

The glowplug relay gets 12v as soon as you switch the key on, and as far as I know even after it trips back out, it's still got power. Correct me?

Again, I don't know if the ignition functions only as a switch disconnect or if it shuts power... but the horn doesn't sound with the ignition off either.

[dukegrad98]

Why not just run a relay triggered by the ignition itself?

Cheers, John

[pawoSD]

There's a few circuits inside the fusebox that only get power when the ignition is on....fuse #4 comes to mind...I don't even know what is powered by it, but I remember reading that somewhere....

The glow system idea is good too. The relay does indeed have power whenever the ignition is on, its up to the relay to click off in the correct amount of time. Adding another relay to that line would probably not affect anything at all.

[dwoloz]

Thanks guys

Tapped into the windshield wiper motor. Was a violet and black wire in the number 1 position but be careful, theres multiple violet and black wires in typical Mercedes wiring fashion