nile13

Can someone point me to pictures or a clear description of the difference in connectors between heated and non-heated seats in 996, 997 and Boxsters?

In other words, is it possible to identify the seat as heated or non-heated once it's out of the car? The switches in both cars are on the dash. So what are the tell-tale signs of a heated seat?

Additionally, does anyone have pics/experience removing OEM brackets from 996 and 997 seats? Are they the same? Can 996/Boxster brackets fit a 997 seat?

What does this have to do with a 993 you ask? I'm trying to Frankenstein some heated seats into my car.

craig001

I hope someone posts the answer as I am thinking about doing this to the 96. I was at the BK site and looking at their seat mount kit, the 996 and 997 mounts as the same. Do not know about the connector pin-out though.

shadow993

The connectors have to be broken down on the 997 & 993 to wire the 2.

Real easy as long as you don't have memory seats!!!!

nile13

Wiring should not be difficult as David mentioned. It's determining whether the seat is heated or not - that's tough when the seats out of the car.

David, I still want your seats Seriously, do you still have them? That would solve my issues. As one SY owner to the other?

shadow993

I still have them and i'm not anxious to sell, but my wife is tired of the 3 pairs of seats I have for the car. Toss me a pm with an offer including shipping. I've shipped seats and all and all... I can install seats faster than I can properly pack and ship.

I sent you and email regarding a pic of a 997 seat wire harness w/o heat. I just need your email address.

aircooled

Mike.S

There is no easy way from just looking at the connector on the 997 seat to determine if it has "heat". One way is to trace the wires coming out of the connector.

My 997 seat install was on a basic seat--NO MEM ORY. Followed the attached link;https://rennlist.com/forums/993-turb...n-a-993-a.html

Heat is nice but the Alcantara inserts work quite well in cold weather, well not as great as heat on second thought!!

nile13

Jim, what would the wire be traced to? Somewhere inside the seat cushions? I'm wondering if anyone knows the colors of those heating wires. Thought I've seen that information somewhere.

aircooled

Sorry Mike, Can't help you on the specific wire for heat, maybe others can chime in....

Pcar416

997/987 there is a red wire with purple stripe coming out of the harness from the seat. This is the power to the heating element. Unlike the seats in a 986/996 (and likely 993), there is no relay in the actual seat itself to control hi/low temp.

In the 987/997, the heat is regulated by a switch on the center console which holds a constant current in the 'hi' temp, and will pulse on/off every 5 seconds in the 'low' temp position. Temp is not controlled by a relay which swaps between serial/parallel config like in other cars. I would use your own switches to power the seat heaters, but you might be stuck in the 'hi' temp position unless you find a way to pulse the current on/off.

jz993

Here is what I found taking out the drivers seat of my 2003 C4S today.


On the floor. Not what I expected from descriptions/diagrams on the forum.


There's a black plastic box at the front, which has a circuit board.




Here are the connectors for the seat cushion heater (left) and the back heater (right).

jz993

FYI: the 3 squarish receptacles in the lower left corner of the black box were unoccupied. I only had to undo the long thin white plug next to them, then 2 plugs next to that. Previously, the 3" square black box where you pull the lock straight out, and as you do, the plug starts coming out on its own.



Finally, my question: If the back and bottom cushions have separate connectors, why do they both go out when only one is broken?
In my case, the switch flashes the red light when touched, doesn't stay lit. The backrest heater (solid red and red/white wires) shows continuity. The left connector (White/red, and brown wires) is dead. Perhaps the brown wire is the ground for both elements? Guess they are connected, even if it doesn't seem so.
So I guess my next move is to strip the bottom cushion of its cover to examine the heating element. Not relishing the job...
Thanks to anyone who can offer advice.

GC96

From what I recall when I put 997 seats in my car, the back and bottom cushion elements are wired in parallel. When one of the elements is burned out, the resulting resistance seen by the controller would be higher. That resistance higher resistance could be used as a signal of a failure in the circuit and the controller might prevent the use of that seat heater. I would presume that the 996 seats function in a similar manner.

GC

jz993

Thanks, GC. I took the cushion out today and found the burn mark and broken wire. I might do a "how to replace seat heater on a 996" if theres is any interest, and I survive the process. lol.

SpawnyWhippet

I'd be very interested in reading a DIY on the seat heater repair

jz993

There is a DIY on here if you search.
Basically:
Raise the seat to max. height.
Remove floor bolts.
Move seat to a neutral fore-aft position, then remove + cable from battery.
Disconnect plugs from harness to remove seat from car.
From there you just patiently undo whatever is holding the bottom cushion to the seat frame, and the cover from the cushion.
You should plan on replacing the bottom cushion. When I peeled the heating element off mine, chunks of foam came with it.