Heated seat wiring

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Themasteryeti
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Heated seat wiring

Post by Themasteryeti » Sat Nov 18, 2023 8:59 pm

Noticed the other day that the wording from under the driver's seat and come out, now I presume that this is for the heated seats, now judging by the other seat it looks like they're just soldered to the metal bar that holds the seat cloth down but I'm not quite sure, could anyone confirm this for me? Cheers 😁

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1973 vw beetle
1993 480s

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jifflemon
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Re: Heated seat wiring

Post by jifflemon » Sat Nov 18, 2023 9:39 pm

There's two heated pads, one in the backrest, one in the base.

Those wires look like they've pulled out from the multi plug - check the wiring underneath the seat

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jamescarruthers
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Re: Heated seat wiring

Post by jamescarruthers » Sun Nov 19, 2023 3:06 pm

Also, it is nigh on guaranteed that the wires on the lower seat pad to the thermostat will be broken. I had mine out last week and attempted a repair, it lasted about two arse cheeks before coming out again. Will be attempting a cheapo eBay retrofit tomorrow as the 480 is doing another week of daily duty next getting hammered to work.

The pads are connected in series, so the break in the bottom cushion knocks the back rest heating out. You can check the resistance of the pads from the plugs under the seat, there should be a few Ohms resistance, not open circuit. This requires you to use your electrician brain when checking the resistance of the backrest if the bottom part has a break in the wires.
1987 Volvo 480 ES, 507274, 217 - Red (Ness)
2006 Citroen C6 Exclusive 3.0 petrol/LPG
2008 Mini Cooper convertible (Mau)

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES auto
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo auto
E981 KHM -- ES (509849)

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Themasteryeti
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Joined: Wed Aug 24, 2022 11:20 pm

Re: Heated seat wiring

Post by Themasteryeti » Sun Nov 19, 2023 3:40 pm

jifflemon wrote:
Sat Nov 18, 2023 9:39 pm
There's two heated pads, one in the backrest, one in the base.

Those wires look like they've pulled out from the multi plug - check the wiring underneath the seat
Definitely from the pads, ends are soldered and the other end still in the plugs!
1973 vw beetle
1993 480s

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Themasteryeti
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Re: Heated seat wiring

Post by Themasteryeti » Sun Nov 19, 2023 3:42 pm

jamescarruthers wrote:
Sun Nov 19, 2023 3:06 pm
Also, it is nigh on guaranteed that the wires on the lower seat pad to the thermostat will be broken. I had mine out last week and attempted a repair, it lasted about two arse cheeks before coming out again. Will be attempting a cheapo eBay retrofit tomorrow as the 480 is doing another week of daily duty next getting hammered to work.

The pads are connected in series, so the break in the bottom cushion knocks the back rest heating out. You can check the resistance of the pads from the plugs under the seat, there should be a few Ohms resistance, not open circuit. This requires you to use your electrician brain when checking the resistance of the backrest if the bottom part has a break in the wires.

Tbh I can't stand heated seats, but as it's there I thought it might as well be fixed instead of two wires hanging about 😂

So test resistance and see if that's okay then try take the seat cover off and either solder back on or buy a new cheapo pads from eBay would be the best bet?
1973 vw beetle
1993 480s

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jamescarruthers
480 Is my middle name
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Joined: Mon Jul 07, 2003 3:19 pm
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Re: Heated seat wiring

Post by jamescarruthers » Sun Nov 19, 2023 8:40 pm

I'd certainly give repair a go. I was lucky with one car and my repair to the thermostat lasted but not on this one, the wire is just too thin and brittle I guess. The break will likely just be on the bottom part and the thermostat can be reached with just the cover opened up, rather than full cover removal, which is trickier than it looks.

The seat is is unweildy so I prefer to split to before removal. If you wind the backrest back, you will see two roll pins that are the hinge-- they are only held in with a Terry pin. Then you can take the backrest out, test that for resistance; then take the base out and work on it in a more manageable way.
1987 Volvo 480 ES, 507274, 217 - Red (Ness)
2006 Citroen C6 Exclusive 3.0 petrol/LPG
2008 Mini Cooper convertible (Mau)

Previous 480's:
J123 CFU -- ES
J449 MNL -- ES auto
D864 CPV -- ES
L691 JFC -- Turbo
F70 MNR -- ES
H858 FGV -- Turbo auto
E981 KHM -- ES (509849)

Alan 480
480 Is my middle name
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Joined: Sun Aug 28, 2011 9:03 am
Location: Aberdeen

Re: Heated seat wiring

Post by Alan 480 » Wed Nov 22, 2023 11:14 am

jamescarruthers wrote:
Sun Nov 19, 2023 8:40 pm

The seat is is unweildy so I prefer to split to before removal. If you wind the backrest back, you will see two roll pins that are the hinge-- they are only held in with a Terry pin. Then you can take the backrest out, test that for resistance; then take the base out and work on it in a more manageable way.
and if the 'pre-tensioners' are fitted make sure disabled
just saying........
Alan

480 ES 2litre 'Celebration' ? , C30 1.8ES, SS1

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