Fuse Size For Heated Seats

[Gary406]

does any1 know whats the right fuse to use on my electric seats ..

1.which fuse for the electric motor wire
2.which fuse for the heated elements

my ecu requires 2 power wires. 1 for the motors and 1 for the heated seats .

i dont want to use to big of a fuse and risk the chance of it going up in smoke

[steve_earwig]

Electric seats - 20 amps each
Heated seats 15 amps both.

[Gary406]

only 1 wire connects to the motors . so only 1 fuse

[steve_earwig]

That's how it works coming from the factory but if you've only got 1 wire then it's probably not ideal to stick a 40 in there. I've not sat in an electric seat (chair?) for a few years so I can't remember if it's possibly to make the motor work in 2 directions at once, if so then worst case scenario is 4 motors running together, so measure the current of one running and times it by 5 and that'll cover the lot.

[Gary406]

thank you

when i tested my seats i had the switch going forward at the same time as the back section going back.

so i think all 4 motors will work at the same time yes.

i could just put a 5 amp fuse in and get both seats moving. if it pops put a 10amp in . if that pops put a 15amp in

or is that not the way to test it ?

[steve_earwig]

All four on each seat? This is getting complicated I guess it's unlikely that all the motors on both seats will be going at the same time, I'd still measure 1 and times it by 5. Or do the fuse thing, if you can spare them

[Gary406]

ye will do that., thanks

[lecky4]

Measure 1 and multiply by 5? why not just replace with the same size as is fitted (presumably blown) as long as it's the correct rating.

[steve_earwig]

He's sticking them in a car that never had them, there's no wiring and he's only got 1 feed wire, as opposed to the two the real thing has.

[Gary406]

ye. the wire kit ecu is a modified one from a coupe 406.

my car does not have leccy seats atm. i'm fitted leccy leather seats with heated option as well ..

[lecky4]

OK, sorry I understand now. I would normally say just run a new cable in with an in-line fuse. You could still do this by spliceing it into the one coming off the ECU. However if the current draw is significantly high you don't know what damage you could do to the ECU (don't know why pug involved that). So in this case I'd agree the easiest thing to do would be just use the existing wire with a tap off after the fuse but always make sure you operate only one seat at a time. To calculate the fuse rating properly you need to find the resistance of each motor/heater (simply measure with a multimeter) and work out the current draw from there and go for a fuse higher but as close as possible to that. The other suggestion would be just take two new cables off the battery connector, why does it have to go through the BSI/ECU anyway?

[steve_earwig]

The seats have their own ECU, it's a D8 so no BSI to worry about. Ordinarily the driver's seat comes off of 3 fuses (plus the one to hold the memories) - the one that actually works the motors is 20 amps, the passenger side is separate and has another 20 amp fuse. Whoever cobbled Gary's wiring together figured its new owner wasn't going to worry about their car catching fire.

[Gary406]

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT

plod has used a kit like this and has had no problems with it.

[Gary406]

i'll just stick a 5amp fuse in. work the seats . if it pops put a 10amp in and so on untill the seats stop popping the fuse

[plod]

http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... K:MEWAX:IT

plod has used a kit like this and has had no problems with it.

When I di mine I did so with a little assisstance on the wiring side from a mate who studied in electronics for 7 years
I fitted the fuse rating he advised on
I've had no issues with the seats, and i've literally just been out to the car, and I have a 15amp fuse fitted