urQ electricals, again

[raf40@oes.amdahl.com (Richard Funnell)]

Hello, people

Last week, I had a recurence of a problem I'd experienced a while back.  My
turn signals intermittently wouldn't work.  When they were dead, the
emergency flashers and intermittent wipers wouldn't work either.  I thought
I'd fixed this last year when I found that the emergency flasher switch was
bad (ignoring the wiper correlation).  It was bad, but obviously it wasn't
the only thing that was.

This weekend I worked through the schematic, found one mistake in it, and I
think found my problem.

The mistake (please correct me if I'm missing something):

The diagram for the wiper motor seems to suggest that the contacts in the
motor assembly (switch that indicates when wipers are parked) connect the
12V motor supply directly to ground when the wipers aren't parked.  The
diagram shown in the first few pages of the electrical section of the
maintanance manual (not the Bentley) shows the correct diagram for the
motor.  The contacts should connect that 12V to another lead going to the
relay.

Having sorted that out, the only common item to the intermittent wipers and
the flashers was the relay ground in the fuse/relay panel.  I checked that
ground, and found that it was high resistance.  I created a jumper from L15
(spare relay position) to the ground cluster on the left side of the
footwell.  When I pulled the wiper relay to measure the ground voltage, it
was solid.  So far, everything's been fine.  Keeping fingers crossed ...

If anyone wants to know the most intimate details of the flasher and wiper
circuits, email me privately while my memory's fresh.




Richard Funnell,
San Jose, California
'83 urQ
'87 560 SL