George Klass

Hey guys,

I scored a really nice set of 91-92 tails

I always thought it using an early 1991 harness makes it plug and play in an 89.

I bought what I believe is an early 91 harness but it doesn't seem to have the plug that goes to the trunk pull down sensor? Am I just asleep or they are not compatible with an older car.


Thanks!!!

scooter

iTrader: (11)

The harness connector for your 89 and the 91/92 is different. GM also made different harnesses for every car, so if the car that you got the harness from did not have the pull down, it won't have the connectors.

You will just have to re-wire your harness to work with the combination of the 91 lights, or mod the 91 connector to plug to your 89.

George Klass

Thanks Scooter. The seller confirmed the car it was pulled from had the earlier style pull down motor. I guess at this point I'll probably just mod the 91 harness.

Drew

iTrader: (58)

It shouldn't be difficult. The tail light wiring splits out of the harness shortly after the connector. Unwrap the part of the harness from the connector to the split, un-pin the trunk wires from the connector. Do the same with the donor harness, and pin your existing trunk wiring into the harness that matches your lights - Done. Took about as long to explain that as it'll take to actually do it, aside from peeling and wrapping tape.

scooter

iTrader: (11)

Unless his connectors are the same, the pins are different. My 88 Firebird and 91/91 Birds have different connectors

Drew

iTrader: (58)

You mean everyone doesn't have a box of spare GM terminals?

While I considered the possibility that they could be different, I kinda assumed that since he didn't mention that the plugs are completely different, that they'd be the same.

I'm not really sure all the variations of wiring harnesses back there, since there's a pretty good gap between the pile of 86 Firebirds I've owned and the pile of 91s. To the best of my recollection, the 91/91.5 harnesses used the same connectors. I know the 86s used a wide flat connector, instead of the square-ish connector on the 91, but couldn't say when GM made the changeover. Still easy enough to change the pins if need be.

George Klass

Thanks for info, much appreciated!

My 89 uses the wide connector. I'll try and play with both harnesses in the next couple of weeks and let you guys how it works out!

TTOP350

iTrader: (8)

On base bird tail lights its as easy as changing out the 2 outer light sockets.
Not sure much different the T/A tails are but shouldn't be much more than that?

George Klass

I'll investigate a little further

Drew

iTrader: (58)

I'm not sure about the 89 harness, but the connector used on 91-92 is still available as a Delphi part. I think I'd probably separate the trunk wiring from the original harness, and pin it into the 91-92 T/A harness. Then remove the connector on the car's tail harness and pin it to use the 91-92 T/A style connector. That way it'd become plug and play, with no splices to worry about, and it'd use the more modern connector.

Alternately, a person could repin the 91/92 T/A tail harness to use the 89 connector.

Further still, a person could fab an adapter that would plug into the 89's harness, adapting it over to the connector to plug into the 91/92 T/A harness...

TTOP350

iTrader: (8)

I set my 89 up with weather pack connectors for the 2 turn signal sockets so I can swap them back and forth from stock lights to the 92 T/A tails without messing with the complete harness.
Took a few mins to set up but makes it quite literally a snap to swap back n forth.

George Klass

Heavy options haha!


Ttop that sounds ideal!