E34 Aux Water Pump

["Brant M. Miller" <brant@xxxxxxxxxxxxxx>]

All -

Forgive me, for I have sinned!  The advice I offered
below is incorrect.

The F9 fuse that protects the aux water pump motor
also protects the horn, the air conditioning compressor =

clutch, and perhaps the auxiliary fan.  That provides
a few more things to look at!  Brant

Mario -

It is always a bad idea to increase fuse size.  The fuse
is there to prevent more extensive damage when one =

item in a circuit fails.  For example, it might prevent damage
to the aux water pump relay or the wiring in the event of
an aux water pump motor problem.

The circuit protected by the 15 amp aux water pump fuse
in a '95 525i contains only the aux water pump relay, the
motor, and wire.  If the fuse fails repeatedly, one element
of the circuit is defective.

I believe the only function of the aux water pump is to improve
the effectiveness of the heater.  I would pull the fuse until
I figured out what was causing the problem.

Brant

>Date: Fri, 18 Jun 1999 08:06:24 -0400
From: Mario Santos <msantos@domain.elided>
Subject: E34 Auxiliary water pump

Hi all,
        I have a question regarding the auxiliary water pump. My auxiliar=
y
water =

pump fuse (15 amp) keeps blowing after about a week running. I'm not sure=
 =

of the exact function of this waterpump, however, I tried putting a 20 am=
p =

fuse and that one blows after about a week as well. Is it safe to run =

without an auxiliary waterpump and how can I check to see what the proble=
m =

is?
        Right now I'm running the pump with a 30 amp fuse and it hasn't
blown yet. =

Is this safe?
Any info would be appreciated

Mario

1990 BMW 525I<

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