I'm in the process of adding power options to my Formula. It's going well enough so far, but for the life of me I can't figure out how to add the trunk light.

Specifically, I'm lost on where the wiring is even supposed to go. Is this part of the taillight harness that comes in somewhere I just can't easily identify because it doesn't exist?

Ultimately I'm fine with running wires or jacking into whichever at C250, but I'd prefer to do it as close to correct as possible. If not correct, then looking for good ideas

You need a factory service manual.
http://www.fieronews.net/fusion/downloads.php

Spoon

[This message has been edited by Spoon (edited 11-01-2019).]

Was that an option?

I think All Later trunk latches are already wired for a light because same switch on latch for ajar light.
All needed is a light between C500 H9 orn/dr blu for power and F8 wht/orn to switch for 88 Fiero (Colors for Body side of C500)

Factory truck light is fairly useless because where installed. Often is buried by whatever cargo and/or blinds you opening in dark.
others have added using different lights, LED strips, etc.
small section(s) of strip LED under the trunk seal on latch side might work better. Doesn't have to be very bright either.

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave

So where is the wire supposed to actually route through the trunk wall? There's a hole on my 85, but 88 had nada. Ultimately if I have to cut that hole, I can. I'm putting in a cruise anyway, so I could route it through the same wiring and just cut the hole next to the cruise mount to hide it better.

To the point of replacing the light entirely - Yeah, I get that for sure I may even do that too. But I've added all the other lighting, so wanted to do this for completeness.

no.
Is no wires to trunk w/o this option beyond C500.

Latch wires go thru the lid to get to the latch and switch/solenoid on it.
Connection for this is below right lid hinge. Car side has 4 wires, lid side 3 wires to switch and 4th to Trunk PL only for cars w/ that option.

quote Originally posted by Spoon: You need a factory service manual. http://www.fieronews.net/fusion/downloads.php Spoon

Has took down Haynes book years ago under DMCA notice by Haynes. And all FSM to prevent same from GM Legal at same time.

I got the lid wires taken care of the other day. Pulled the solenoid off the '85 and bought a lid wiring harness with all 4 wires in it. I understand completely what you're saying there. Aiso have the 88SM

Mostly I figured I had to be missing something with the routing of the wires. I guess not though. Gotta get creative if I really want to put it back...

quote Originally posted by N0ctrnl: I got the lid wires taken care of the other day. Pulled the solenoid off the '85 and bought a lid wiring harness with all 4 wires in it. I understand completely what you're saying there. Aiso have the 88SM Mostly I figured I had to be missing something with the routing of the wires. I guess not though. Gotta get creative if I really want to put it back...

trunk wires likely is in taillight wires and likely grommet/plug is hidden in right side of car near rear of strut tower. Grommet w/ wires if you have the light option or plug w/o this.

Or it goes all the way to Cruise servo side have grommet/plug on left side somewhere.

If you drill a hole for LED or whatever trunk light mods, make sure you deburr that and wiring is protected too. If allows water in, use RTV and coat in layers if needed to build up a seal there. Myself, I won't use OE location for reason above. Is a gray plastic "plug" to cover light hole so all trunk "carpet" can use same piece.

Just unscrew C500 from car and connect to those pins in the back. See my Cave, Terminal Access to get more space to solder or whatever w/o cutting.

I'm an idiot. I found the plug there it should go through. It's - surprise - right behind where the cruise would mount. Not sure how I missed that before.

Thanks tshark for setting me straight.

So hopefully the last question - where should the +12v come from for the light? In the manual it says "Feed - Body & LGTG" but I can't find anything else that matches up to that.