E46 2004 - heated seats both base and backrest?

[Funk]

Just a quick one; with the heated seats on an E46, should both the base and the backrest warm up? The base gets nice and toasty but I can't feel any heat in my back...

[duff]

Pretty sure it's only the base that heats on mine.

[2 GKC]

Pretty sure backrest should heat up too. Thermostat seems to have gone in mine so they get bloody hot

[Funk]

Interesting, this was where I got to the other night researching it. Can't find a definitive answer as to whether mine should heat the backrest as well.

[GTEYE]

Both base and backrest definitely should heat up - if they are working correctly obviously.

[Smuler]

GTEYE said:

Both base and backrest definitely should heat up - if they are working correctly obviously.

I agree. Just sat in my E46 M3. The heated seats work and are as good as those in the E92 I had. I'd say to the touch, I found the base seemed to generate most heat, at least at first, but both parts are definitely providing warmth.

[Funk]

Ok, something to add to the list for investigation...

[Smuler]

Funk said:

Ok, something to add to the list for investigation...

When I had my first E46 and it had a few niggles, such as needed to reset throttle adaptions (neat trick), key issue etc.I got a lot of technical help from this site and it's predecessor (same guys)
Circa 2011-2014, the majority had E46's so plenty of knowledge. don't think it's changed, plus I got a forum discount at Harry Fairbairn for parts

http://www.bmwforums.info/

[Funk]

I'll have a sit in the passenger side with the seat on and see what that does - I can't imagine both would go at the same time unless the base/backrests are on separate fuses and they are and that's what's blown. If the back of the pax seat warms up then there's an issue with the driver's one...

[Funk]

Ok, passenger seat gets warm on both base and back.

Wasn't quite sure what I was looking for but I stuffed the camera under the seat to take a pic from the back and found this:





I'm not sure where it's supposed to connect to but a) it looks like it's been sheared/torn and b) I can't imagine it should have been left like that underneath. I suspect that it may well be the cable that connects the back heater and has been snagged somehow which has torn it?

I will try and get under the pax side tomorrow in the light and see but I thought I'd throw it out to you guys here as someone will most likely know!

Cheers.

Edited by Funk on Wednesday 21st December 18:52

[JakeT]

I can't say this will be the same for the E46, but sometimes the elements get ruined by specific pressure on a part of the seat (think kneeling on the seat). But it is the backrest, so might be less likely. I would imagine those are the wires you need and you are correct, all of the seat heats up.

[Funk]

Well this'll be the cause then:



That's a green/violet and brown pair of cables chopped off under my seat...

[Herbs]

Be careful if reconnecting.

That looks far too clean to be wear and tear or sheared by moving the seat. I know some BMW heated seats have a habit of shorting and sending the temperature rocketing - it's entirely possibly that could have happened to yours and it has been disconnected rather than repaired although it tends to be the base it happens to rather than back rest.

Hopefully that isn't the case but go in with your eyes open.

Edited by Herbs on Thursday 22 December 10:02

[Funk]

I'd be surprised if someone cut that (knowing what they were doing) and left it like that....?

[Herbs]

Funk said:

I'd be surprised if someone cut that (knowing what they were doing) and left it like that....?

You never know - plus if that is the cable that comes from the heating element then it isn't live.

[Funk]

Herbs said:

Funk said:

I'd be surprised if someone cut that (knowing what they were doing) and left it like that....?

You never know - plus if that is the cable that comes from the heating element then it isn't live.

That one comes from the connector at the front of the seat as far as I can see. It looks like the other part would be in the seat back (remember it's the base that's working, the backrest isn't).

[Herbs]

Funk said:

Herbs said:

Funk said:

I'd be surprised if someone cut that (knowing what they were doing) and left it like that....?

You never know - plus if that is the cable that comes from the heating element then it isn't live.

That one comes from the connector at the front of the seat as far as I can see. It looks like the other part would be in the seat back (remember it's the base that's working, the backrest isn't).

Judging by the diagram above it looks like it is the wire (one of a pair at the bottom) that connects to the connector and then attaches to the heating element in the seat back. This would explain why the base still works as identical wire number 2 is actually connected between the base and the connector.

[Funk]

Herbs said:

Judging by the diagram above it looks like it is the wire (one of a pair at the bottom) that connects to the connector and then attaches to the heating element in the seat back. This would explain why the base still works as identical wire number 2 is actually connected between the base and the connector.

Indeed.

I may get someone to look at it properly; I suspect the back of the seat will need removing to repair it properly and the gidgets that secure the backplate are 'single-use' and prone to breaking if you try to remove them apparently...

At the moment I have a warm backside which will do - I'll put in on the list of remedial works for after Christmas.

[Funk]

....aaaaaaaaaand fixed.

It was the snapped wire under the seat. My love-handles are now toasty and warm as well.