Driver's Seat ECU

Talk about the 406's electrical system, what wires do what, how to add extra functionality, etc.

Moderator: Moderators

Post Reply
Sage103
1.6 8v
Posts: 19
Joined: Wed Nov 01, 2017 5:47 pm

Driver's Seat ECU

Post by Sage103 »

This is only week2 of my 406 adventure but it came with a fault which I really need to crack - the driver's seat (it's an Executive estate) doesn't move in any way. Passenger seat is fine. Fuses are good. Can anyone suggest the likely cause? Faulty ECU? Or faulty switch? And given that the Haynes manual is fairly useless in this particular area can someone point me towards the ECU? I've seen the post regarding bypassing the ECU but I think I'll leave it if all else fails.
Thanks
Gordon
User avatar
Doggy
Mod with a 2.2 HDi, De-Fapped!
Posts: 10710
Joined: Mon Oct 13, 2008 11:49 pm
Location: Northants

Re: Driver's Seat ECU

Post by Doggy »

Hi & welcome aboard. 8)

Not heard of any similar problems. Mine had the up/down not working on the driver's seat when I got it, (but the motor was operating). That was a detached flexi-drive that just clipped back in.

IIRC the motors are all essentially the same, but those on the drivers seat have position encoders and the passenger seat doesn't. Maybe you can connect a plug from one side to the other to narrow it down?

The ECU lives under the driver's seat.

If you memorise the positions, (press/hold button 1 or 2 until it beeps), then adjust your door mirrors do they go back to the memorised position when you press the button a second time?
2002 HDi 2.2 Exec Estate, (2008-12) (wonderful)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
GingerMagic
3.0 24v
Posts: 3570
Joined: Fri Apr 06, 2012 9:02 pm
Location: Bournemouth

Re: Driver's Seat ECU

Post by GingerMagic »

Check your mirrors first.
If the mirrors or mirror switch is unplugged or a broken connection then your drivers seat will not work.

You can get a switch from a non-exec and plug it into your seat ( big orange connector, just leave the switch connected but just hanging down ) which will bypass the memory ECU and allow you to move the seat until you find a fix.
2003 2.2hdi estate - mine
1998 Volvo 940 auto estate - also mine
2019 Citroen C3 something - the wife's
PP2000 user, can help with faults / diagnostics in the Bournemouth area.
Sage103
1.6 8v
Posts: 19
Joined: Wed Nov 01, 2017 5:47 pm

Re: Driver's Seat ECU

Post by Sage103 »

Thanks for these replies. The mirrors are also dead so bypassing the ecu with a non-exec switch looks promising. Coincidentally the nearside mirror has been pranged so maybe worth checking its internals when daylight returns. Meanwhile I have ordered an ecu off eBay but I'll just keep that in reserve for now.
Post Reply