RE: wiper fuse keeps blowing

["Buchholz, Steven" <Steven.Buchholz@kla-tencor.com>]

... just checked out the wiring diagram for the '83 QTC ... What I found was
that there are separate taps on the wiper motor for normal vs. high speed
operation.  Normal speed is powered by the Grn/Blk wire attached to terminal
53 on the motor, while high speed is powered by the Grn/Yel wire attached to
terminal 53b.  The wires from the fuse box to the wipers are on connector
"C" (pins 6 and 16 respectively), and the wires that go to the wiper switch
are on connector "E" of the fuse box (pins 18 and 21 respectively).  The
wires should be the same color on either side of the fusebox.  BTW, the pin
numbering on the wiper switch is exactly the same as that at the motor (53
and 53b).  

While anything is possible, the fact that your wipers work on low speed
tends to indicate that the wiper motor itself is OK.  I'd look for some sort
of short circuit in the harnessing ... perhaps testing at each connector
into the fusebox.  

Good luck Dave!
Steve Buchholz
San Jose, CA (USA)

> -----Original Message-----
> Patient: 83 urquattro
> Problem: wiper fuse (#11) keeps blowing when high speed 
> wipers are engaged
> Configuration: old style fuse box with stock wiring.
> 
> The wipers and washers work in every other mode, but when the 
> high speed is
> selected, the fuse blows instantly. I checked out the wiring 
> schematic and
> it 
> appears that when high speed is selected, all the current 
> goes through the 
> stalk switch and through the motor. Any tips on how to debug 
> this problem?
> Should I try to measure the current the motor is drawing? Or 
> should I buzz
> out continuity on parts of the circuit? Or rig up a fused 
> test wire and see
> if
> the  wiper motor will run in high speed mode?
> -
> Dave Lawson
>