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D2 - Everything else Anything that doesnt fit elsewhere

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  #311  
Old 31st January 2020, 01:49 PM
HPsauce HPsauce is offline
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I did have that thought myself Mark, but remember the brake lights are effectively "always live". So I expect it's a safety issue (and maybe even embedded in the regulations somewhere) that brake lights are on a very direct failsafe circuit, hence no relay.

Could you respond to my earlier question:
Quote:
What sort of symptoms were you getting that made you decide to change the switch, and did you use VCDS to get it set correctly or just judge it by when the brake lights came on?
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2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!
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  #312  
Old 31st January 2020, 02:41 PM
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moltuae moltuae is offline
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Quote:
Originally Posted by HPsauce View Post
What sort of symptoms were you getting that made you decide to change the switch, and did you use VCDS to get it set correctly or just judge it by when the brake lights came on?
Sorry, I didn't notice that question.

I had the symptom of restricted power from stand-still, usually at a junction or traffic lights, after I'd been holding the car for a while on the footbrake. There's a hesitation for a few seconds, like the ECU 'thinks' you still have your foot on the brake, which I suspect is the contact sticking.

I also had one or two mysterious ABS faults stored. The first brake switch I had replaced was probably about 8 years ago, so I can't remember if I had the restricted power symptom back then too. It had gone into the garage for some remedial work, which including fixing an intermittent ABS fault. It was the garage who diagnosed the brake switch to be the cause. They were perplexed as to why a brake switch would cause such a fault but a new switch seemed to cure it.

Similar symptoms started appearing again a while ago. This time I replaced the switch myself with a Meyle equivalent. I don't remember having to do any adjustment; I just screwed the switch in. I did check it though, but with my OBDeleven device/app, in which I could see each of the live switching states, much like you can in VCDS.
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  #313  
Old 31st January 2020, 02:55 PM
HPsauce HPsauce is offline
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Cheers Mark, sounds similar enough to my experience to make the same cause/fix plausible.

Quote:
Originally Posted by moltuae View Post
There's a hesitation for a few seconds, like the ECU 'thinks' you still have your foot on the brake, which I suspect is the contact sticking.
Though given the way the switch operates, with the released brake pedal arm forcing the spindle of the switch in to disconnect the brake light circuit, it's probably something slightly more complex than contacts sticking.

I'm reluctant to swap the switch in winter weather, easy though that may be in isolation. I don't have a garage/workshop to work in and there's a lot of extra equipment and wiring in and behind the drivers knee cubbyhole and panel that makes removing it non-trivial.
And some of that isn't working properly so if I do go in there I'll be committed to other jobs too: Xcarlink, Bluetooth, DVB-T tuner, receiver for reversing camera radio signal and relays to manage all that without draining the battery.
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!

Last edited by HPsauce; 1st February 2020 at 11:36 AM.
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