No, the wire that seems to come from the ignition switch is really a
ground wire of sorts, through the starter motor coil. The voltage that
triggers the relay comes in on the blue wire, from the alternator. If
you have something other than a Bosch alternator the blue wire may not
work anymore.

Mark

Rick Foster wrote:
>  Thanx Craig for your reply.  Maybe I was bit hazy in my problem.  I'm good about the Dometic's operation, and it is all good when I bench tested in the garage.  I'm ready to reinstall and was checking the 12v wiring in the van and found the problem I described.  I checked all the circuits with the a) ingnition off, b) ignition on, and c) with the engine running. I don't have power to the relay accept from Bat at term 87.  Is this supposed to this way?  Seems like there ought to be power to the #12 wire coming into term 85 which connects to the ignition switch.  Hope that helps to de-fog my delema.  Thanx for any help!
>
> Rick Foster
> 85 westy
> "Cassidy"
>
>
>
>  Now I'm stumped and stymied with getting back on the road with my Dometic working.  It never has, but with help of Lorean and Ken, I took it out, refurbished it, bench tested each system and it worked. Before putting it in, I tested the 12v input and here's what I've got:
>
>   1- no auxillary battery, just stock wiring to'refrigerator heater relay'(bently 97.32.e), plan to put in aux bat in future.
>
>   2- clean wiring from relay thru fuse block and to ignition switch.
>
>   3- + Power from bat at term 87 thru term 30 to frig connection.
>
>   4- continuity in blue wire from term 87 to D connection at the
>       alternator.
>
>   5- No Power at term 85 from the ignition switch but + continuity thru this wire to the ingnition terminal (term 50).  This term is coupled with a #10 wire that goes I know not where. Bently (97.62) looks like it's track 78, but it looks like it goes off where 'no man has been before'! I can't read any 'track 78' anything functional and I'm not spark engineer. Spock where you!
>
> Date:    Mon, 8 Jun 2009 22:58:36 -0700
> From:    craig cowan <phishman068@GMAIL.COM>
> Subject: Re: problem with 12v power to dometic frig- long
>
> The first thing to keep in mind is that the fridge on 12v only works while
> the engine is running, and takes quite some time to "warm up". If you have
> the fridge completely off and turn it onto 12 v and drive for 2+ hours,
> you'll feel the fins getting cold. If you just drove around town....i
> wouldn't expect much of anything. The 12v selection is really just to keep
> things cold while driving
>
>
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