scoper

My 78 928 has wires under both front seats that end in a male plug. There is no female match to be found. Since M437/8 are listed as option codes for power seats, I'm assuming that's what they are for. What the earliest car with the power seats?

linderpat

interesting. I didn't think 78's had power seats. What are the last 4 digits of your VIN, and do you know your build date?

scoper

My VIN ends in 0576. The build number is 3011 which is much later than the VIN would indicate I believe Jim thinks it would have been built in June or July of 78.

scoper

My VIN ends in 0576. The build number is 3011 which is much later than the VIN would indicate I believe Jim thinks it would have been built in June or July of 78.

928cs

What is the complete VIN?
Just want to be sure that this is a 1978 MY and not a 1979 MY produced in 1978.

linderpat

interesting. My VIN ends in 834, and a build date of May 1978.

scoper

9288200576

linderpat

It's definitely a 1978, US spec car. Weird that you have an earlier VIN than me but a later build date. I have no wire harnesses/pigtails under my seats.

Ramp

Does anyone know if you can take the entire mount with motors etc and simply swap seats ? I have an 86 with half power (4 way up/down) but can get a set of full 8 way power seats. My seat bottoms and backs are better and the right color - can I simply remove the bottom/back and put it on the full power base ?

drooman

928 #1 and #2 and #24 all have the power seat wiring pigtail for both front seats. The earliest car I’ve ever seen with the power seats themselves was fall of 1978 (79 model)

Petza914

I put 12 way seats from a 90 GT into my 79 and just connected the main power and ground spade terminals and all the power functions worked (except maybe the seat heater). I've since replaced them with 997 seats.

Ramp

Thanks Petza, good to know the power terminals should work. Need to find out if I can simply unbolt my seats and bolt them to the new base.

Petza914

I pulled the large wire round plugs for power and ground from the multi pin connector, and made an adaptor wiring harness that went from those pins to the female spade connectors I needed to connect them under the seat. That way, no cutting or splicing of wiring and they could be put back to stock, which I did when I sold them.

I would assume the mounting bolt pattern was the same in 78 and 79 and I was able to bolt in the newer seats using those rectangular mounting blocks. May have used them at all 4 corners vs just the 2, but don't fully remember now.

The other thing to keep in mind is the seat belt buckles and receivers are different. The newer ones have the buckle receivers mounted on the seats themselves vs the older ones where the receivers are mounted to the center tunnel and the buckle that goes into the receiver aren't cross compatible. I ended up removing the belt receiver from the new seats and using the older one mounted to the car.

In the pic where the drive cable is loose, you can see the seat side of the wiring adapter, then just married the other end to the 2 spade terminals from the harness in the car.