[Vwdiesel] Electrical Weirdness

[Roger Brown]

David Cook wrote:
> Hello all-
> 
> Forgive me, I'm actually working on the boat this time
> but I figure I've got the best chance for help with
> you guys.
> 
> Last week we had it out and there was a short with the
> trim pump.  This killed the battery in short order.
> 
> Today I'm trying to find where the short or problem
> might be.  
> 
> Do I remember correctly that one way to determine if
> there is a power draw somewhere is to connect a test
> light between the battery and a cable?  If the light
> lights, then there is a draw, and if it doesn't there
> is no draw?
> 
> Is there any good test I can do to determine if the
> short is actually in the pump, it's solenoid, or the
> wiring?  I know that last week there was something up
> with the pump because it wouldn't quit running.

Yes, you can use an unpowered test light like that, will give a qualitative reading, for 
quantitative, use an ammeter in place of the light.  To isolate, use the divide and 
conquer approach.  Isolate down to the circuit to where the current drain is coming from. 
  Then on that circuit, disconnect things until the drain falls off.

-- 

   Roger