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D2 - Engine Bay Everything under the bonnet

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  #1  
Old 25th November 2013, 10:36 PM
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Thanks, I will do some research. Don't want to solve problem by disconnecting electrical connector though.

ELSA term of the unit is "pump valve unit". It consist of coolant circulation pump V50 and two heat regulation valves N175 and N176.

Coolant ciculation pump V50 will have two 1sq.mm. wires attached to it: red/yellow from battery via fuse and brown/green from HVAC unit with switched earth.

Interestingly, N175 and N176 valves are connected via 3 pin connector T3q (brown/yellow, brown/white and red/yellow) located in plenum chamber on right side where as pump V50 is connected 'directly' without any connector ...
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Last edited by notorious; 25th November 2013 at 10:59 PM.
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Old 26th November 2013, 07:37 AM
HPsauce HPsauce is offline
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Quote:
Originally Posted by notorious View Post
Coolant ciculation pump V50 will have two 1sq.mm. wires attached to it: red/yellow from battery via fuse and brown/green from HVAC unit with switched earth.

Interestingly, N175 and N176 valves are connected via 3 pin connector T3q (brown/yellow, brown/white and red/yellow) located in plenum chamber on right side where as pump V50 is connected 'directly' without any connector ...
Now that is "interesting" in a number of ways:
1. The 3-pin connector is there, very obvious. Same place as on PF.
2. There was a 2-pin connector in the same location on my PF S8 and ALL pictures of the pump unit show both connectors - each on a short lead!
3. Where is the fuse and is it ONLY for the pump (you know what I'm thinking)?
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions and extended leather. Ski hatch retrofit. Aftermarket reversing camera. DVB-T and XCarlink now removed as redundant.
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". (Even rarer than a D2 S8!) 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. Agate Grey/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. Added Auto-dim mirror, Leather seats, 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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Old 26th November 2013, 07:52 AM
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The fuse is not just for the pump of course.

I would make an assumption that the 2pin electrical connection is on the pump body itself, so it doesn't show as a separate connector in the middle of the loom in ELSA.

Here is picture of D3 unit: http://www.ebay.co.uk/itm/AUDI-A8-D3...item3f2b5ae0d6. On the left hand side of the picture the plastic motor chassis finishes with something that looks like an electrical connector.

I didn't find D2 picture from 2002 model car.
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Last edited by notorious; 26th November 2013 at 08:12 AM.
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Old 26th November 2013, 12:13 PM
HPsauce HPsauce is offline
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Quote:
Originally Posted by notorious View Post
I would make an assumption that the 2pin electrical connection is on the pump body itself
I've made some progress and indeed it is.
Must have been a "late revision" on the D2 as all the units ever pictured look like the attached photo, with 2 fly leads and large connectors.

Managed to follow the loom and find where there's a 2-pin plug directly onto the pump body. But it's a swine to get at and I can't even see how it's latched on, let alone get any fingers or tools anywhere near it.

But the 2-wire loom itself is neatly wrapped in Certoplast and quite accessible, so I'll be chopping into that some time in the next few days to break one or both circuits and "possibly" install a connector for "future use" (or maybe not )
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__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions and extended leather. Ski hatch retrofit. Aftermarket reversing camera. DVB-T and XCarlink now removed as redundant.
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". (Even rarer than a D2 S8!) 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. Agate Grey/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. Added Auto-dim mirror, Leather seats, 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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  #5  
Old 26th November 2013, 12:53 PM
HPsauce HPsauce is offline
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Well as "Dear Prudence" was told "The sun is up, the sky is blue" so no time like the present for a 10-minute job.

Tape snipped open, wires identified (there's a 3-core loom in there too of thinner wires going off elsewhere so a bit of care is needed) and the switched earth snipped and tied back. All properly tied up with Certoplast again.

Silence reigns.
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions and extended leather. Ski hatch retrofit. Aftermarket reversing camera. DVB-T and XCarlink now removed as redundant.
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". (Even rarer than a D2 S8!) 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. Agate Grey/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. Added Auto-dim mirror, Leather seats, 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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  #6  
Old 26th November 2013, 01:42 PM
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I'm not entirely convinced that the only purpose of that pump is the REST function.

Can it be a something like a "turbo timer" cooling feature that provides cooling for the hottest parts of the engine *after* the main coolant pump has stopped? It may well be that some areas of the engine need some coolant traffic after everything suddenly switches off?
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Old 26th November 2013, 01:45 PM
HPsauce HPsauce is offline
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No, it ALWAYS goes off immediately you turn the ignition off. And it's for flow to the heater matrix, not the main radiator.

It presumably has "some" function in normal running, otherwise it would be idle in normal operation. Or maybe, just maybe, that would have created other problems/cost/complexity and it was easier to just leave it running?

I think it also has a function of improving flow to the heater matrix, especially on a cold start, but even on the coldest days I didn't notice much difference when I disabled it on my PF S8.
I'll find out tonight as I'll be doing a few short journeys late into the evening.
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions and extended leather. Ski hatch retrofit. Aftermarket reversing camera. DVB-T and XCarlink now removed as redundant.
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". (Even rarer than a D2 S8!) 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. Agate Grey/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. Added Auto-dim mirror, Leather seats, 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; 26th November 2013 at 01:49 PM.
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