Seat heaters

[dragonflyjewels]

Has anyone tried changing seat heaters ? We recently put a half leather interior in one of our 480's, looks great but the passenger seat heater doesn't work. The old cloth seats both had working heaters, but it looks quite a challenge to swap them over. Before we try, I wondered if it might be a fault on the wiring rather than a duff heater. Is there already a thread on this subject ? I can't find one, so would greatly appreciate some words of wisdom.

[jamescarruthers]

Hi Sylvia,

In my experience, it tends to be that the wire has failed at the internal temperature sensor. This is just from mechanical wear and tear and can be resoldered.

It's not the easiest to get to the seat heaters but if you are careful you can bend the staple-like clips and take the covers off the seats to access them. Once the covers are off its quite simple.

You could measure the resistance of the seat heater before you strip the seatdowofirm if there is a broken wire. If it is open circuit then you have a break. Also, as your seat heaters worked before that proves that your car is delivering power where it should and that it is the seat heater at fault.

I think some people in colder countries have wired in Webasto seat heaters in lieu of the original Volvo ones

[jifflemon]

I've not done it on 480 but have added seat heaters to other cars in my fleet.

There's a how to from GlasgowJim in the how to section for taking the covers off, it's a fairly straightforward job. My top is that on reassembly, instead of using hogrings, use very small cable ties. Much easier to work with!
If you do decide to use hogrings, but the hogrings pliers (they're less that £10 on eBay) a much easier that trying to use a pair of long noses pliers!

[AleksanderHugo]

Apart from wires around the temperature sensor, it is quite common that the wires between the seat and the backrest break. As others said, start with measuring the resistance to find the faulty part (as far as I recall it should be something around 1.5 Ohm for each half of the seat). Just remember that the temp sensor may open the circuit in the lower part due to the temperature

Below you can see where the sensor is in the seat. Give yourself some time to get inside of the seat

(and no, I did not leave that cardboard there inside of the seat )

[dragonflyjewels]

Thank you so much guys for all the useful tips, I'll print it off for hubby and get him cracking on it on a sunny day when the temperature isn't minus whatever !

[jifflemon]

*cough* ideal job to bring indoors....

[jamescarruthers]

In the unlikely event that your seat heater thermostat is broken, then it can be found at Scandex here: http://www.skandix.de/en/spare-parts/in ... g/1059304/