rear demister not working.

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

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millard
1.8 16v
Posts: 97
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rear demister not working.

Post by millard »

The rear demister button on my heater control lights up for a few seconds then dies.
Any idea where I start looking please?
I'm bloody hopeless with electrics.
On the plus side,,, I have a voltmeter, and I ain't afraid to use it : :mrgreen:

Cheers
Millard
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Captain Jack
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Joined: Sun Aug 07, 2005 11:26 am
Location: Langford, Somerset

Re: rear demister not working.

Post by Captain Jack »

Check the relay - it's under the drivers side dashboard to the right of the steering column.

I guess you checked fuses etc.?
2003 - 2008: 1998 Peugeot 406 2.1 TD 110bhp LX Saloon
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp :twisted:)
2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
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Doggy
Mod with a 2.2 HDi, De-Fapped!
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Re: rear demister not working.

Post by Doggy »

Maybe a bit of a pattern emerging here?

If you've got no power to the hrw or either door mirror heater with the relay closed, I'd be checking fuse 'c' on the outside of the BSI and MF5 in the engine fusebox.

If the relay's dropping out on its own, this could indicate a problem with the relay, (which I reckon is R5 in the BSI), or the PCB.

It's meant to drop out after 10 minutes, but as far as I know the timing is another BSI function.
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)
millard
1.8 16v
Posts: 97
Joined: Sun Nov 07, 2010 8:22 pm
Location: Bournemouth

Re: rear demister not working.

Post by millard »

Thanks fellas, I'll check today and report back.
Millard
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Captain Jack
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Posts: 3820
Joined: Sun Aug 07, 2005 11:26 am
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Re: rear demister not working.

Post by Captain Jack »

Ah yes, BSI... When I fitted the fog-light capability to my D8, I just had to put a new relay in but with the D9, it will be different.
2003 - 2008: 1998 Peugeot 406 2.1 TD 110bhp LX Saloon
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp :twisted:)
2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
millard
1.8 16v
Posts: 97
Joined: Sun Nov 07, 2010 8:22 pm
Location: Bournemouth

Re: rear demister not working.

Post by millard »

Well I checked the relevant fuses and all's OK there.
I can see the relay in between the bank of 6 fuses under the steering wheel column, but don't know how to remove it or check it. Any ideas please guys?
Cheers
Millard
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