Re: beastly issues

[human <human@nh.ultranet.com>]

-- [ From: human * EMC.Ver #2.5.02 ] --

>The other problem is weird and is dangerous as well.
At certain times, driving along with the lights on, the lights will cut out
along with anything wired to come on with the ignition.   There is a common
trick on VWs and some Audis that works like this.  If you have forgotten
your key but need to close your power sunroof or windows, turn the lights on
, and push the "flash to pass" lever.  The powered accessory will magically
work. I'm not quite sure why, but it does.<

Having just spent ten or twenty hours learning the ins and outs of complex
relay banks using standard (parts bin) Bosch relays in various "and" gate
conditions, I will try to take a stab at some of this.  You may be
experiencing unplanned current tracking.  The reason for the VW/A trick you
mention is that the flash to pass feature sends power to something which is
normally only on with the ignition, and this voltage can now flow back
through the rest of the "ignition only" harness.  neat trick. 

I just realized that the way the car is wired, relays would have nothing to
do with this problem. duh.  Can you incite this failure mode at will to test
it? (of course not!)  I would nominate the ignition switch as a possible
source of your problem.  The flash to pass would then throw some extra
voltage at that momentarily broken contact and arc it back into operation.

Congrats on finding the loose alternator connection, I went through hell
with one of those a couple of years ago.

So anyway what I learned (about relays...) is that current can flow through
two relay coils from a partial "on" condition (ie, 12v at 85, no ground at
86 but 86 in parallel with another relay which has 85 grounded for some
unintended reason) resulting in them both turning "on".  This is because it
only takes 6-7 volts to trigger the relay solenoid.  the only solution I've
come up with so far is to add diodes to the coil inputs to control current
flow direction.

hasta!
--
Huw Powell

HUMAN Speakers
7 Kelsey Road
Lee NH 03824

http://www.thebook.com/human-speakers