V8 Seat Heating Element Repairs

[Roland Broberg <broberg@execpc.com>]

I've done the V8 driver's seat a couple of times.  First time it went I thought I
had a sore on my left thigh as it kept hurting periodically.  Later I discovered
that the heat was not working and ultimately connected the two issues.  The usual
failure point is the outer edge of the lower cushion where one first sits and last
lifts from the seat.  Stresses are greatest at that point.  You can check the
elements without removing the seat.  Connectors are at the front of the seat near
the memory control box.  Check power source first.  With the heat switch on you
should have 12V at the 6 point connectors T6c/1 which means connector T6c/pin #1
under both seats.   c is driver's side d is pass side in the US.

Driver side connector and wire colors as follows:
T6c/6 Seat back Br/Blue is hot, T6c/3 Br is ground
T6c/1 Seat bottom Blk/Yell is hot
T6c/5 The other side of the bottom is the Br/Blue that goes in series to the seat
back (T6c/6)

Pass seat connector and wire color as follows:
T6d/6 Seat back Br/Blue is hot, T6d/3 Br is ground
T6d/1 Seat bottom is Blk/Red hot
T6d/5 The other side of the bottom is the Br/Blue that goes in series to the seat
back (T6d/6)

You can separately test seat and back cushions for opens. Backs test resistance
between T6/3 and T6/6.  Bottoms test resistance between T6/1 and T6/5.  Either
seat.

Some have done repairs in the car.  I prefer out. Assuming you have a failed
bottom cushion, here are the steps( I have never done the seat back):
Remove plastic caps on runners behind seat
Tilt seat sort of vertical
Power the seat all the way back and all the way up
D/C the phone-it has modular connector
Remove two bolts at front rails
D/C connectors
Slide seat rearward using some kind of carpet protection to keep grease from
staining as the greased seat guides get exposed from the slide rail-I use a thin
pliable putty knife on both sides
Remove set through front door
Best access is achieved by putting seat up on a low bench or horses
Remove switch assy from side and D/C it
Remove plastic guards on both sides of seat hinge-the inner one has a trick-There
are two small plastic pins in the face of the cover.  They look like mold points
but you have to push them in until they fall through.
Remove round plastic caps on hinge
Remove large philips screws under those caps
Pry the hinges apart
Lift away the backrest-carefull to guide the wires-I had to cut a wire or two as
they were wrapped around some hardware.
Turn over the seat base
Access the wrapped spring wire (1) on each side by the hinge and carefully unwrap
it from the tabs.  This loosens the tension holding the seat leather to the metal
base.
Remove the several pressed in plastic buttons that hold the leather in place
Unhook the leather from the bent metal tabs
Now, you should be able to lift the foam and leather away from the metal seat
base.  It may have some stick to it but not much.  Was not originally glued but
age makes it stick.
Take a break and move to comfortable seating with table with the cushion
Dissect the cover from the foam as needed-not all of it.  Start with that outside
thigh area and peel the leather off the felt layer.  The element is in the felt
layer.  All this is fairly sturdy stuff.
As you expose the element layer you may immediately see a burnt spot.  I did once
and not the second time.
If you see the spot you can dissect the felt away from the element and pull a bit
of wire out for repair.
If you do not see the spot then it gets trickier.  Take your handy VOM and clip a
fine needle in one lead and the other connect to the supply at the connector.
Work your way along the wire-you can see the track of it as it weaves around the
surface-poking the needle into the insulation until you find the break.  Not that
bad actually.
To fix the break, after dissection, twist & solder the wire.  It is nichrome or
similar metal and it does not like to be soldered but it can be done.   New
element is about $350 US last I checked.
Tape minmally-don't want a lump and it's going to get warm anyway. Put extra felt
over the spot and I added a layer of thin cardboard to spread of surface tension
out over the fix.  Does not show.
Test and reassemble.
Enjoy the heat!

You can get an upholstery shop to do all this except the element repair.  While
you're at it this would be a good time to replace that cracked piping around the
edge of the seat.  I got mine done for $60 which I considered outrageous but it
sure looks good.


FBFISH@aol.com wrote:

> In a message dated 12/5/98 4:38:00 PM Eastern Standard Time, WARATAP@aol.com
> writes:
>
> << + new seat heating element for driver
>  (It might still get cold this winter)
>   >>
> Ingo- My V8 has a bad seat heating element also. I removed the whole drivers
> seat from the car and isolated it to element. Can you share some of the
> details ie repair versus new element, how much upholstry work involved (I hate
> that)---- TIA
> Frank Santoro

--
Roland Broberg
W319N657 Shagbark Glen
Delafield, WI 53018-2818
broberg@execpc.com
broberg@cpg.mcw.edu
Current: 90V8Q, 86 4Ks, Fmr:91 100, 86 5KTQ, 84 5K