Date: Thu, 24 May 2007 21:07:11 -0500
Reply-To: Matt Roberds <mattroberds@COX.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Matt Roberds <mattroberds@COX.NET>
Subject: Re: 1984 Westy pops fuses when running fan and windshield wipers
In-Reply-To: <20070525004810.XCNN17229.fed1rmmtai112.cox.net@fed1rmimpi01.cox.net>
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
> From: Kris Seago <kseago@MAIL.UTEXAS.EDU>
> Date: Thu, 24 May 2007 11:16:10 -0500
>
> Here's one that's plagued me for a while: If I have the fan on
> "high" (and in Texas summers, it's almost always on high) AND I turn
> on the windshield wipers, the fuse for both will invariably pop. Fan
> on low or medium doesn't pop the fuse.
It could just be that the motors involved are old and drawing more
current than they used to. But you can check it out a little bit. Are
the terminals in the fuse box really tight on the fuse? In other words,
do you have to work at it to push the fuse into its place, or does it
just fall in there? If it just falls in there, see if you can figure a
way to rebend the terminals in the fuse box to make better contact with
the fuse. If these terminals are loose, the terminal and the fuse will
heat up, which puts the fuse just a little bit closer to blowing.
If you've got a voltmeter, you might measure the system voltage with
everything (blower, wipers, lights, etc) turned off and the engine
running and revved up a little (say 2000-2500 rpm or so). It shouldn't
be very much over 14.0 V - if it's considerably higher than this, your
alternator may need attention.
Another test, if you have a digital multimeter with a 20 A range: Take
out the fuse entirely. Set the meter to 20 A and stick the probes where
the fuse was - one probe on each terminal. Run just the wipers (at each
speed) and note the readings, then shut off the wipers and run just the
blower (at each speed) and note the readings. Don't worry if the
readings are negative - that just means you have the probes backwards.
(You can do this test with an analog multimeter too, but most of them
don't have a high enough current range, and you have to *know* which way
around to put the probes.) Anyway, the readings may show you which
device is more of a current hog. I haven't got a van Bentley but the
bay Bentley says the wiper motor should draw about 2.5 A on low and
3.5 A on high with the blades puleld away from the windshield. The
blower will probably be more than this but I don't have a good number
for it.
You could go through both the wiper and blower circuits and make sure
all the terminals are clean and tight. Loose connections would tend to
add resistance and make the motors draw _less_ current, though, but it
can't hurt much to take a look.
Matt Roberds
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