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Flat battery, v. high current drain - Fuse No. 8 under bonnet. Water pump continuous...

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Smartbear
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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Smartbear » Sun Nov 05, 2017 8:42 pm

Is it possible the switched 12v supply from fuse 1 could be not switching off due to a relay stuck “up”
Rob
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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Sun Nov 05, 2017 8:44 pm

Great! Thanks Stuart. That seems to align with this https://www.youtube.com/watch?v=5P5i-c7F7AE. He really goes to town with his testing equipment. I notice a couple of things. From his scope the current draw was in the same sort of region that I have and I recognised the noise.

I also see someone else has posted a comment "I worked at a BMW dealer for 4 years, and both the thermostat and the coolant pumps were high failure items. The coolant pumps would fail intermittently like you experienced, or they would completely fail. When they failed completely you would know right away because the coolant fan would kick on high at all times as a fail safe." (I guess he means pump rather than fan).

I'll see what happens to Fuse 1 with ignition then get it booked in. I don't have much of an appetite for doing that without a lift....
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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Smartbear » Sun Nov 05, 2017 8:48 pm

Newbers wrote: Sun Nov 05, 2017 8:44 pm Great! Thanks Stuart. That seems to align with this https://www.youtube.com/watch?v=5P5i-c7F7AE. He really goes to town with his testing equipment. I notice a couple of things. From his scope the current draw was in the same sort of region that I have and I recognised the noise.

I also see someone else has posted a comment "I worked at a BMW dealer for 4 years, and both the thermostat and the coolant pumps were high failure items. The coolant pumps would fail intermittently like you experienced, or they would completely fail. When they failed completely you would know right away because the coolant fan would kick on high at all times as a fail safe." (I guess he means pump rather than fan).

I'll see what happens to Fuse 1 with ignition then get it booked in. I don't have much of an appetite for doing that without a lift....
He could mean the fan & not the pump, when my pump was failing (but still working) the coolant fan would be on at varying speeds as soon as the engine started-I didn’t recognise this as normal & diagnostics revealed a failing pump (implausible pump speed) :?
Rob
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e89 Sdrive 30i, this ones busted, pass me another...
e85 3.0si sold

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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Sun Nov 05, 2017 9:21 pm

Interestingly the cars done <>75,000 which seems to be when they gone. I guess I'm going to have to get it done sooner or later so better not to have to get carried 100 miles home by the AA. My local specialist will want to use BMW parts so I expect that to be eye watering. Already in the last 30 days: Road tax, 2 x tyres, MOT, battery, Gearbox + diff oil. Ouch!
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Smartbear » Sun Nov 05, 2017 10:24 pm

Newbers wrote: Sun Nov 05, 2017 9:21 pm Interestingly the cars done <>75,000 which seems to be when they gone. I guess I'm going to have to get it done sooner or later so better not to have to get carried 100 miles home by the AA. My local specialist will want to use BMW parts so I expect that to be eye watering. Already in the last 30 days: Road tax, 2 x tyres, MOT, battery, Gearbox + diff oil. Ouch!
The pump is made by pierburg not Bmw, they just put it in a pretty box and double the price. Get it from eBay and save some money :thumbsup:
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e89 Sdrive 30i, this ones busted, pass me another...
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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by ph001 » Mon Nov 06, 2017 12:45 am

Yep, £250 from Ebay and defo under an hour to fit. If you are paying more than £350 you are being robbed. Another £50 for the stat gets you to £400.
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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Mon Nov 06, 2017 9:08 am

I'll report back when I have the quote....
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Mon Nov 06, 2017 8:02 pm

Anyone happen to know who makes the OE thermostat? (Not that the OE version is of a quality to boast about....)
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Mon Nov 06, 2017 8:09 pm

Newbers wrote: Mon Nov 06, 2017 8:02 pm Anyone happen to know who makes the OE thermostat? (Not that the OE version is of a quality to boast about....)
Seems to be a lot of brands making this part:

BEHR:TM 14 97
BORG & BECK:BBT221
ERA:350337
GATES:TH39797
JP GROUP:1414601119
MEYLE:328 228 0005
QUINTON HAZELL:QTH640K
SASIC:3306083
SWAG:20 93 0265
TRISCAN:8620 23197
VEMO:V20-99-1277 - V20-99-1277-1
WAHLER:410086.97D0 - 4689.97D0
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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by bradz » Mon Nov 06, 2017 9:11 pm

Buy the BMW thermostat, The aftermarket ones all seam to be in a plastic housing.
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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Mon Nov 06, 2017 9:45 pm

Stuartt wrote: Sun Nov 05, 2017 8:10 pm Ok from what I can work out, the pump has 4 wires, 12v from fuse 8, switched 12v from engine control relay via fuse 1 , earth , and a control wire from pin 26 on the ecu.
Check that fuse 1 goes dead when you switch off the ign if it does then the fault probably lies within the water pump as it appears the control module is built into it.

Hope this makes sense.

Stuart
Pulling fuse 1 didn't stop the pump from whirring. I got about 6v across the terminals (with fuse out obviously). It seems pretty clear that the fault is either in the thermostat or the pump control.
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Mon Nov 06, 2017 9:53 pm

bradz wrote: Mon Nov 06, 2017 9:11 pm Buy the BMW thermostat, The aftermarket ones all seam to be in a plastic housing.
Are they not supposed to be plastic? RealOEM shows it that way.....
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Mon Nov 06, 2017 9:53 pm

Newbers wrote: Mon Nov 06, 2017 9:53 pm
bradz wrote: Mon Nov 06, 2017 9:11 pm Buy the BMW thermostat, The aftermarket ones all seam to be in a plastic housing.
Are they not supposed to be plastic? RealOEM shows it that way.....
Coupe, KW coil overs, PSB limiters, Powerflex ARB bushes, 18" CSL reps, Aero skirts, ZHP leather knob, Whippy and proud. Probably needs a wash :roll:

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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Newbers » Mon Nov 06, 2017 9:54 pm

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Flat battery, v. high current drain - Fuse No. 8 under bonnet...

Post by Stuartt » Mon Nov 06, 2017 10:05 pm

Newbers wrote: Mon Nov 06, 2017 9:45 pm
Stuartt wrote: Sun Nov 05, 2017 8:10 pm Ok from what I can work out, the pump has 4 wires, 12v from fuse 8, switched 12v from engine control relay via fuse 1 , earth , and a control wire from pin 26 on the ecu.
Check that fuse 1 goes dead when you switch off the ign if it does then the fault probably lies within the water pump as it appears the control module is built into it.

Hope this makes sense.

Stuart
Pulling fuse 1 didn't stop the pump from whirring. I got about 6v across the terminals (with fuse out obviously). It seems pretty clear that the fault is either in the thermostat or the pump control.
Seems to me like the relay within the water pump has stuck in the closed circuit position causing it to constantly run then.
I guess you'll be replacing the pump then for sure.

Stuart
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