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Old 10th May 2018, 03:47 PM
JulianHicks JulianHicks is offline
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Join Date: Jan 2016
Location: Ashford, Kent
Posts: 246
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Quote:
Originally Posted by 27litres View Post
I dealt with a parasitic drain on my D2 for a long time before I eventually solved it.
I had a bung voltage regulator on the alternator.
It 'tested fine' with an auto elec.
It measured 13.7V running with lights on full beam and aircon on.
Parasitic drain remained until I went with my gut and replaced the Voltage Regulator (and bearings and slip ring).

So you just have to figure out now whether the D3 battery monitor is capable of picking up a failing voltage regulator?
Marty; thanks for your comments but I believe the D3 alternator is more advanced than the D2 one; the D3 one is water cooled and has variable Voltage output based on what the Battery Manager [BEM] asks it to produce.

The attached diagram shows only one connection from the BEM to the alternator [in blue] and that's its 'voltage request line', I believe.

As per my comment to SRG above; I guess it needs a voltage check for the alternator output to see if it's giving the 14.3 it's asked for. If it is, I think I might have 'voltage drop' but I've no idea how that battery current gets to and from the front of the car.

Julian
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