Date: Tue, 15 Jul 2008 15:56:53 -0400
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: common electrical problems in vanagons
In-Reply-To: <00de01c8e6ae$4123c3a0$0101a8c0@gp207joel>
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At 03:09 PM 7/15/2008, joel walker wrote:
> 1. Ground Cluster - under dash, left/driver side,
> above fuse box.
> push-on connectors become corroded/dirty
> and fail to make consistent electrical contact.
ALL wiring that carries significant current: deterioration of
wire-to-terminal crimp, evidenced by melted insulation at
crimp. Same can be caused by poor connection of push-on terminal,
but less common in my experience (the ground terminals are a special
case because they're plugged onto steel tabs when they're meant for brass).
> 2. Fan Resistor - Radiator Fan
Only on later, single-speed fan motors.
> 3. Fan Resistor - Rear Seat Heater Fan
>
> 4. Fan Resistor - Dash Heater Fan
Dash heater fan switch is overloaded on high position and eventually melts.
Dash heater fan circuit is overloaded on high position.
Cure for both problems is to add a relay and new feed circuit for the
high-speed position.
> 5. Power Windows
>
> 6. Power Door Locks
>
> 7. Ignition Switch - steering column
Horn slip-ring contact on steering wheel wears through.
> 8. Headlight Switch - dash instument pod
License plate lights internal parts are made of steel (thank you
Hella) and corrode.
> 9. Engine ground strap - left/driver side of engine
>
>10. ??
2.1 ECUs have overheat problems with ignition drive transistors.
All ECUs have problems with solder fatigue. A real PIA in every way.
Temp gauge flashing light fails in flashing condition due to leakage
in internal capacitor aggravated by humidity-induced leakage across
circuit board. Cure by disassemble gauge, replace electrolytic cap
(preferably with a tantalum), clean circuit board. Requires
moderately delicate soldering and drilling out faceplate rivets.
New-type Westy water level sender (wand extending into tank) is
designed to fail either by physically breaking internal switches if
wand is flexed even slightly, or by failure of upper seal allowing
water ingress -- a drop or two is enough to make it
malfunction. Latter failure often evidenced by changing behavior of
the lights after the panel is powered on.
>so do we want to identify the problem area and location, and then
>state the likely cause of the problem, and then the/a cure?
I think a hugely valuable meme to introduce into this culture would
be the understanding/belief that electrical supply problems are
actually quite easy to diagnose definitively; that it's generally
better to do this than rely on shotgun approaches; and that a
voltmeter, a length of wire and a pin are all that is
needed. Basically a supply circuit is a long string that goes from
battery plus to battery minus, and the entire battery voltage is
distributed along that string in an orderly way. When the circuit is
working correctly, almost all the voltage appears between the plus
and minus terminals of the load -- headlight or whatever. But when
it *doesn't* i.e. when the load isn't getting the supply it should,
the place or places where the voltage *does* appear define the
location(s) of the problem precisely.
>unca joel
--
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage," '85 GL "Poor Relation"
