I have a 1987 camaro RS with a light under the hood. This light , I am guessing is supposed to come on when you open the hood. does any body know what turn's the light on and off ? There is only one wire to it and that is a ground wire, It seems to have a vacuum line to it ? I cant find anything on the elec schematics or vacuum diagrams.

 

It should definitely be in the wiring diagram, I believe in the interior lighting section.

 

Mercury switch. You should have one wire with a connector along with a ground wire.

JamesC

 

That make's sense. But is there any reason for a vacuum line to be hooked to it. Maybe thats why it has never worked. I have a chiltons for the camaro, but none of their schematics show the under hood light. Is there some other schematics I should get.

 

I have no idea why a vac line would be in place in that position. If the wire with the connector was there, you could, of course, check it for power. Mine's covered with a loom, so perhap the wire in question is buried in there somewhere.

A shop manual will have the diagram.

JamesC

 

It's supossed to just have one wire to it, and that should be a power wire, not a ground.

 

Well I guess somebody used the light fixture for a plug for the vacuum line, be it that it was run inside the wire loom from the harness to the light. There is no wire in the loom to the light from the harness other than a ground wire that grounds the hood light fixture to the engine compartment. Guess I'll get a shop manual so that I can possibly find the correct wire. Thanks alot guy's.
Ron

 

If I remember correctly, the hood wire on mine was red or orange. Can't tell you exactly where it came out, but was in the pass side really close to the strut tower. The light housing shouldn't need a ground, it should ground itself since it's bolted to the hood. Hood is grounded being that it's bolted to the body.

I actually removed my underhood light, and used the wire from it, connected to a switch, and installed 2 14in LED strip lights under the edge of the front of the hood, just behind the hood latch. They point towards the bay, light reflects off the hood the entire way down, so the light is always from above. They work really well, veryt very bright, yet not in your eyes, and lights up the entire bay really well - I can actually work under the hood at night with these things and no other light.

 

Thanks so much!!! The led light bars sound like a great idea!!! Thanks again

 

I double-checked my 85. There are two wires as I mention above. The ground wire, according to the shop manual, is a 'strap, hood to body.' Perhaps the set-up is different in other years.

JamesC

 

Oh - might be extra ground straps in some years - mine doesn't have one.

This is like the LED strips I got:http://www.autozone.com/autozone/acc...ier=60068_0_0_

They are flexible SMD leds with sticky tape on the back, and I placed so they faced down the hood, shining away from you, on a little edge that is just behind the hood closure.

 

IN this thread there are a few photos of the wiring for the underhood light in an 82 Cross Fire car.

https://www.thirdgen.org/forums/elec...-disaster.html

Power for the light is picked up from a tap into the blower motor high speed power wire (red wire in the background of the last photo). The power source can be any always hot point in the engine compartment. This way the light will come on if the engine is off. The circuit usually has an in line fuse to protect the wire form the tap point to the light. My 82 car has the fiberglass hood, so the harness has two wires in it. Both are black. The power wire runs through the connector. The ground wire connects to the light base and can be seen looping below the connector in the photo.

The ground wire connects to the metal body at a ground point by the hood hinge. You can also see the copper braid ground wire the connects to the metal backing on the under hood insulation. It connects to the same ground point as the light ground does.

In the end, the lamp needs two wires to work. A power wire and a ground wire. At the lamp, the ground wire should be connected to the metal lamp base. It may or may not be jumpered to the metal hood at that point or run down the harness to another ground point.The power wire to the lamp socket.

 

Again thank you all!!!!! This site is fantastic with a bunch of great guy's. Your suggestions really help, along with the pics. I went to EBAY last nite and got me a service manual ( oem ) THANKS AGAIN
Ron G

 

Oh - forgot about the fiberglass hoods Those would need a ground wire for the light!

 

My 85 has a steel hood with the body ground, which is located just below and behind the pass side hood hinge.

JamesC

 

Hey James, I have a 85 w/ a glass hood. Can you take a couple of pics of the hood light and the wiring route. My original light was destroyed by fire and I would like to get my new one mounted and routed as close to original as possible. Thanks! (I've read lots of your posts since I became a member. Great information from you!!!)

 

Here's the general routing.

1st pic. Gray connector. Follow the loom six inches or so and you can see the in-line fuse.
2nd pic. Over the blower motor and up the hinge.
3rd pic. Note the ground from the aforementioned loom.

JamesC

 

And across the hood. Note the connector and ground wire. Since the light was interfering with my STB, I removed it.

JamesC

 

Thanks James, I assume the light works by turning on the dome light or opening the door?

 

By opening the hood (mercury switch).

JamesC

 

Can you show a pic of the mercury switch? Is it built into the light housing? I have a TPI Harness.

 

I believe it's in the light housing itself.

JamesC

 

Yep, I believe it is, I hooked it up to the battery and tilted it and it came on then tilted it horizontally and it went off.