I have recently acquired a '87 Trans Am. I work at the airport here in Phoenix and have to open the hatch almost every day. On my '92 camaro the hatch release button will work with the car in nuetral or park. But in the Trans Am it will only work if the car is turned off. Is this right?

 

No. The hatch release on an auto grounds through the NSS (Neutral Safety Switch). On a Manual equipped car it grounds through the parking brake. Someone must have rewired it. I'll e-mail you the wiring diagram.

Lon

 

Hm....odd, my hatch release on my car does that too. It won't operate at all, unless the engine is turned off. Are you sure it's not supposed to be like that? Mine's been that way ever since I owned it, I always just thought it was a stupid safety feature - maybe so you couldn't pop your hatch with engine running, let exhaust gases in, etc.

 

Well that is what I was thinking but on the camaro it will not open with the car in gear. But if you go to nuetral or park it will open.

 

It IS a safety feature. The hatch will pop any time the ignition is off. But IF the ignition is on, it will pop only IF the auto gear selector is in Neutral or Park. On a Manual equipped car if the ignition switch is on, it will pop only IF the parking brake is engaged at least one click. In either case the switch is being grounded through either the NSS or parking brake. If you swap a T5 for an auto as I have you'll see that you have to cut the tan/wht wire and re-route it to grounding switch on the parking brake mechanism (same switch that turns on the "BRAKE" light when the parking brake is applied). If you don't when the ignition it on, you'll have to push in the clutch to pop the hatch.

If you have a HELMS manual the wiring diagram is on page 8A-134-0.

Lon

 

lonsal,
My hatch won't pop in ANY gear when the motor is running - neutral and park included. I always just considered it an annoyance, but thought it was normal at the same time....

So this is not normal? That it won't open even in neutral or park with the eng. running? I don't have a helms manual, but I do have a chilton's, and I can't find a mention of the hatch release switch anywhere in the wiring diagrams! Am I just missing something?

 

Well, if you don't have one, (in your case a 1988 Firebird Service Manual) (aka HELMS manual) then yes you are missing a great resource. Lets compare the HELMS manual to your Chilton, Haynes, etc. Take the hatch release solenoid function and diagnosis as an example: The hatch release solenoid is coverred in 3 pages in the HELMS manual. The hatch pull-down unit covers another 3 pages. Another page shows a picture of the entire rear compartment showing component placement and wiring routing. I suppose this explains why these manuals are nearly 3.5" thick and weigh in at nearly 6 lbs. Yes they are expensive (over $100 including tax & shipping when I bought my last one a few years back) but they are worth it. You REALLY need to buy one if you work on your own car. They are available often on eBay for 1/4th the price of a new one.

Lon

link to HELMS Inc.

 

In my 86, the hatch will only open if the ign is off OR the em brake is on. Its an automatic too, and the owners manual states the em brake must be on for the switch to function. When the car is off, hold down the release button and look at the dash where the BRAKE light is. Sometimes you can see it flicker.

In the 92, it will function when in Park or Neutral while the ignition is on.

Somewhere in the years, GM changed it to be a bit more friendly.

 

From my 86 Manual:

 

And that's exactly how my '86 TA works - ONLY if the park brake is applied.

 

hmm...that's something to check out, I never use my parking brake unless I'm parked on a hill, steep driveway, etc. I'd do it right now, but I'm not near my car.

And about the service manual...I have wanted to get one for a while, but every time one comes up on Ebay, I haven't had the spare cash for it. In fact, there's one on Ebay right now, here.... http://cgi.ebay.com/ebaymotors/ws/eB...tem=1873340249

But $45 I do not have, and the bidding would probably go higher than that anyway.

 

I will have to try it with the EM brake applied. That is one angle I have not thought of.

I alos need an Owner's Manual for my '87. The Barrett-Jackson car show is right by my house in January. I can probably pick one up there. Lots of vendors with all kinds of literature.

Thanks guys.

Bill

 

THE PARKING BRAKE MUST BE APPLIED. MY 88 GTA WORKS THAT WAY. IF THE ENGINE IS RUNNING, DA BRAKE MUST BE ON.

 

Hm, that's interesting to note. My 89 could open the hatch with key on OR off as long as it was in Park or Neutral. I've since rewired it to only open if the key is ON. That will prevent anyone from opening the hatch by sliding something long in through the window and hitting the switch as I've done a couple times before. The only way to pop the hatch with the key off is with the remote or with the key itself.

 

Looking at the wiring diagram from my 88 Camaro Service Manual. On an Auto equipped car, (with the ingition on), the gear selector must be in P or N to pop the hatch. The yellow wire of the relay is wired through the NSS. On a Manual equipped car, (with the ignition on), the parking brake lever must be pulled up in order to pop the hatch. The tan with white stripe wire from the relay is grounded through the parking brake switch. That is why we are having differing methods to open the hatch (or tonneau in the case of a convertible) being described.

Lon