charlie31603

iTrader: (10)

I need to know what wires are what on my 87 IROC for the power pull down hatch. I bought a factory service manual, but it dose not have anything on the wiring for it. Just on how to remove it. And I did a search and came up with nothing. I can't use my friends car since his is a 89. So if any one can help that would be great. Thanks in advance!! Adam :-)

charlie31603

iTrader: (10)

Anyone??

Stephen

iTrader: (12)

You'd be surprised at how close a 89 could be to a 87, in regardless to chassis wiring.

charlie31603

iTrader: (10)

I pm'ed him.

We tried for like 5 hours looking at the two and just couldn't figure it out. Adam :-)

1fast97gsx

Actually I need the same info for a 1992 Z28. I'm in the middle of rewiring the car and I have the battery in the trunk. I need the simplest way to get the pull down to work without spending a lot of time to run wires.

BigBadLou

iTrader: (3)

Wow, two days and not a single answer?

I don't have a diagram for your particular year but we have a 1992 diagram for the whole hatch pull-down system. Unfortunatelly, it's stored on our ATGO site (Austin chapter of TGO) and we're moving to a new server this weekend so I can't get to the diagrams.
And I just deleted the back-ups from my laptop yesterday. Smart move.

You can PM Trickster (I hope I'm spelling it right), he has a LOT of diagrams and he sure might have one for your year. I think GM changed the pull-down throughout the years a few times.

Sorry I can't help more right now.
Lou

BigBadLou

iTrader: (3)

Hold on, I found the 1992 diagrams. THey are most likely not the same as the 1985 but will give you an idea.

Hope this helps.
Lou

charlie31603

iTrader: (10)

Thanks Lou. I'll try those out tomarrow. I tried the ones in my friends 89 manual. But no dice. I'm going to pm Trickster also. To see if he has any for an 87 Camaro. What I don't understand is I have a 87 Camaro factory service manual. But it has absolutly no wiring for the pull down unit. Adam :-)

Stephen

iTrader: (12)

On the shop manual, I'm not surprised, to an extent. I get more use out of my Haynes, than my Chiltons. Yet, Chiltons is supposed to be better than Haynes.

charlie31603

iTrader: (10)

I just realized. I haven't checked the Haynes book yet for this. Adam :-)

Trickster

In 1987 and 1988, there were two seperate maintenance manuals for our cars. There was the standard maintenance manual and there was the wiring manual. You have to have both of them and if you got it off e-bay the seller will usually only sell you one of them. I have the schematics and trouble shooting guide on my computer and will e-mail it to you.

BigBadLou

iTrader: (3)

Trickster, any harm in posting the schematics?

Lou

charlie31603

iTrader: (10)

I'll have to see if the guy I got the book from has the other one. But if the other one has the wiring in it. Then why dose this one have the wiring in it also? Atleast know I have the correct hatch wiring thing. So I can see if I can get the hatch to close all the way. And thanks to everyone else that helped!! Adam :-)

Trickster

Just a slight problem with a recent computer crash and having to reload my program for converting pdf files to graphic files. Hope to have resolved shortly. This crash is why you haven't seen me on the boards much lately.

Drew

iTrader: (58)

Sorry for the poor pictures, my scanner is packed up. The 87 diagram is fairly vague, the diagram pictured is from a 91 service manual, but should be the same style unit. Basically the 87 manual shows a red/wht wire from the lid fuse to the b terminal on the hatch relay, with the ground function being handled by the unit itself. The 91 diagram shows all the wiring between the switches and the relay as well as the ground wires and power wire. The wiring between 86-91.5 should be exactly the same, however the harness plugs changed style a couple times. For example, a 1986 pulldown has the same color wires, but the plugs won't physically plug into the harness on a 91.

The hatch pulldown is covered in section 135 of the manual for both 87 and 91.

Trickster

What you have there is section 10H, this gives an overall view of the wiring schematics and cross car wiring. When you get my e-maill you will see what is missing from section 8A which is the wiring and trouble shooting section

charlie31603

iTrader: (10)

I geuss explains the "go to section 8A" part in the manual where it talks about the pull down unit. But when you look in the front of the book, there is no section 8A. Adam :-)

Trickster

You gotum Kemo Sabe, Section 8a is the second manual that I mentioned earlier. BTW, did you get that e-mail I sent you?

charlie31603

iTrader: (10)

Yes I did. Already printed it out and found that I do have power to the unit. and the relay still works. So I thinking it's time for a new unit. Adam :-)

blackchr

I know this is an old thread, but I have one wire I can't figure out on my pulldown unit. This is on an 87 Formula. It's a single white wire that goes to a single-pin connector. It comes out of the relay bundle, but I can't see where it should go to, and it's just hanging now.

Anybody know where I need to plug this in?

Thanks!

lonsal

iTrader: (2)

I love easy questions such as this. On your car the white wire connects to............NOTHING. It was used on 1989-91 to provide ground to turn on/off the hatch light.

Lon

blackchr

I love fast and accurate answers like that! Now I feel kinda stupid for spending 15 minutes standing in the parking lot with the motor 2" from my face, trying to find *anything* that it would plug into.

Thanks! TGO rocks!

Trickster

Sorry to correct Lonsal on this, however, the white wire supplies power to the light in the cargo compartment. Ground is supplied by a black wire.

lonsal

iTrader: (2)

Nope. Check again. The red/white stripe wire supplies +12v. The white wire connects to the black with orange stripe wire to supply the ground.

Lon

Trickster

I am looking at the schematic now and there is not a black/orange wire in that circuit. Remember Lon, this is a 87 formula and not an 89-91 model as you mentioned in your previous post.

lonsal

iTrader: (2)

Look back at my original answer. ..."It was used on 1989-91 to provide ground to turn on/off the hatch light." I already mentioned the white wire connects to NOTHING on 1986-88 models. For thise years the hatch light was controled by a manual switch, not by the striker-sensing switch. Which part do you still disagree with?

Lon

Stephen

iTrader: (12)

I find it hard to believe, GM put a wire in before it was used. If the wire was there, it would have been used for something. If it was used from before, and no longer used, it would have been removed.

TheScaryOne

iTrader: (3)

That's not 100% true.

When you have 1000's of spare wiring harnesses, what do you do? Keep on using them. Better than having to retrain people or retool machines, especially if the problem is that it's one wire. Sometimes being cost-effective focuses on the long run. Retooling the machine that made the harnesses would cost a lot, while the single missing wire would save very little. Considering that 88 is halfway through the thirdgen lifespan, and I believe they had bad sales from 88 until 93, I don't think the retooling would have paid for itself.

But back on topic, I can see how they'd put it in early. They planned it, had it all set up, and the last minute, found some little bug in the system, scrapped it, and put in a manual switch. It's been known to happen.