V6 Xant hot seat regulator and flasher

Stempy · Unread post by **Stempy** » 17 Mar 2009, 16:45

Two questions here, the first regarding the heated seat regulation. Is it based on a simple voltage drop series shunt or is there some sort of complicated pulse width modulation thing going on?

The reason I ask is that having just repaired the back pad in my drivers seat I checked out the voltage on the connector as the seats only seem to have been working on full power for quite some time. On setting 3 there is the expected 13.7 volts, but on the lower two settings, no volts. If it isn't a simple series regulator then I'm thinking maybe I have to wait for the regulator to kick in. Speaking of which, does anyone know where it is?

Secondly, the location of the indicator flasher is eluding me. I can hear that it's somewhere under the steering column but can't seem to see it by just removing the felt trim. Before I start pulling more bits off can someone give me a definite idea of its location?

Unread post by **Peter.N.** » 17 Mar 2009, 17:52

Cant help you with the seat I'm afraid but the flasher unit you should be able to find by feeling all the 'boxes' under the dash with the indicators on, assuming they work, you will feel a vibration in time with the clicks when you've found it.

Stempy · Unread post by **Stempy** » 17 Mar 2009, 18:28

MMmm, tried that, none of them vibrate. AFAIK I'm looking for a grey relay, I know it's in there somewhere, but none of the ones that are visible/feelable seem to be it.

Unread post by **xantia_v6** » 17 Mar 2009, 18:28

To clarify, it is one of the relays (grey or black) next to the under-dash fuses.

Unread post by **CitroJim** » 17 Mar 2009, 19:37

xantia_v6 wrote:To clarify, it is one of the relays (grey or black) next to the under-dash fuses.

Should be one of the ones tucked right back in under.. With the indicators on, hold a screwdriver to your ear and use it as a stethoscope...

The seat regulation is done electronically but how I'm not too sure as I've never dared to dissect a leather seat to find the controller. All I know is the regulator controls are just small switches that select different values of resistors to determine the heat. The switches themselves are quite flimsy and the contacts run around a PCB track. They're not hard to disassemble and being so flimsy, regular use is sure to wear out the tracks and open-circuit them at some settings.

The wiring diagrams are not very forthcoming, just showing an ECU in each seat and a few wires going to the regulator switches.

Stempy · Unread post by **Stempy** » 17 Mar 2009, 19:45

Thanks all

It may just be then that if the ambient temperature is too high then the regulator wont even turn the seat heat on unless you have it on full blast, which I would presume just overrides the regulator.

So the regulator is an ECU in the seat

I worry that things can sometimes be a little too complicated for their own good.

DickieG · Unread post by **DickieG** » 17 Mar 2009, 20:51

The flasher relay is directly under the column, you need to remove the lower column shroud to get to it.

Stempy · Unread post by **Stempy** » 17 Mar 2009, 20:56

Clogzz · Unread post by **Clogzz** » 18 Mar 2009, 12:29

Does that mean found

Item 12, light grey, above the diagnostic socket.

Stempy · Unread post by **Stempy** » 18 Mar 2009, 14:17

Yes I'm all sorted now. Thanks

Did some further testing of the seats, and now all the pads are working I've discovered that they do actually get warm on setting 2 at least. There seems to be some kind of time/thermostatic cycle going on so that they are not supplied with continuous current as they are when set to full.