Wiring an oil warning light in an early car with SC Motor

Elombard · 10-16-2004, 07:30 AM

Turns out the Monster Oil lights are not a super easy install in early cars because we dont have an oil pressure warning light on the dash.

So does this sound like the right procedure?

1. Switched Power to the light

2. tap into the wire on the SC motor harness that comes from the oil presure warning sender (front of motor near firewall). and connect this to the ground on the light.

Will that work? I saw procedure similar but it was on an SC. and they accessed the wire in the dash.

Anybody know what wire or pin this is on the 79 euro harness? before I start looking at wiring diagrams.

By the way anybody know if you can hook one up on a stock early car? there is no idiot light sender? Perhaps one can be added?

TIA

Gunter · Gunter's Garage

Are you sure that there is no oil warning light in the dash? Anyway, if you have a 3.0 liter motor, then you have an oil pressure sender in front (next to the right fan post) and you also have an oil pressure switch mounted on top of the engine next to the breather cap towards the rear (firewall) This switch is just a ground connection (closed when engine not running, but open with engine running when oil pressure activates) It's easy to install a big oil warning light: Wire any 12V source to your big light and wire the ground side to the pressure switch on top of your engine. That's it!

Elombard · 10-16-2004, 10:52 AM

Thanks Gunter. Do you know what wire that is coming out of the harness? or what pin on the connector?

Thanks

Gunter · Gunter's Garage

Forget the harness. Locate a fuse in your front (or rear) fuse panel that only has power with ignition ON. You have to run a new wire from this fuse to the big light, then run another wire (ground) from the light to the switch located on top of the engine. This is the oil warning light switch on the 3.0 liter located next to the oil breather cap. The switch looks like a plug with only one spade connector and is screwed into the case. Just crimp on a female connector to the new wire coming from the light and push it onto the male connector on the switch. With ignition ON, the light should be on. As soon as the engine runs, the oil pressure will open the switch, light goes out. A #14 wire should do it. Look for the oil warning light switch on the engine and let me know if you find it.

Elombard · 10-17-2004, 08:08 AM

Yes

I know where that switch is, it has a wire on it because my car has the 3.0 harness on it. I was just thinking it would be easier to access that wire at the harness, I am not sure I can reach the switch without at least a partial drop? I will give it a shot.

Thanks again

Gunter · Gunter's Garage

You are right about how hard it is to reach that switch, but, by removing the extra fan blower on the left side, and the help of a mirror and light, you might be able to get to the switch. Just unplug the existing connection on it and put your new wire on the switch. If you want to use the existing wire, a schematic is needed for the set-up. On my '80 SC, the wire from the switch is given as GRN/WHT going to the dash warning light which you don't have. Have fun.

Elombard · 10-17-2004, 08:54 AM

Thanks I will have a look.

Early_S_Man · 12:21 AM

EW,

There is a spare wire in your wiring harness for optional rear fog lamp ... #93 White/Green wire terminated/taped up near the factory fog lamp switch position on the dash ... it doesn't go through either 14-pin connector, but rather directly to the left rear tail lamp assembly via the five-pole round connector at the left rear bulkhead of the engine compartment, where it is taped and folded as a two-wire pigtail.

The wire can be intercepted under the relay panel before it gets to the five-pole bulkhead connector ...