Date:         Thu, 28 Jan 2010 17:40:00 -0500
Reply-To:     Kim Brennan <kimbrennan@MAC.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Kim Brennan <kimbrennan@MAC.COM>
Subject:      Re: AC relay question
Comments: To: Keith Ovregaard <kovregaard@GMAIL.COM>
In-Reply-To:  <66C0B402-63FE-4064-B3E2-EB37E2490C29@gmail.com>
Content-type: text/plain; charset=US-ASCII; format=flowed; delsp=yes

In addition to the suggestions of other folk, if your thermostat isn't
working the compressor won't kick in. The rheostat for your
thermostat, is the knob you turn to adjust how cool/cold the AC runs.
It is a variable ohm resistor. It is not impossible for it to go bad
(it did on my 86). It can be pulled out of the dash (or overhead unit,
if that's where it is) and you can check to be sure that it is working
correctly with a volt/ohm meter.



On Jan 27, 2010, at 7:33 PM, Keith Ovregaard wrote:

> Hi Volks
>
> I know this is a bit off-season, but my AC compressor is not engaging
> ever since the alternator went bad. Installed new alt. and it works
> fine, but no AC. Not sure if there is a relationship between these 2
> problems, but my guess is not.
>
> First test I did was to put 12v to the compressor clutch while
> disconnected and it works. The compressor shaft turns with clutch
> engaged and has normal resistance. No power to the clutch wire that
> goes to the relays at the D pillar. See Bentley 87.5 for illustration
> of fuse/relay panel. No blown fuses there or at the front fuse panel.
> There is power to the 2 main leads (red) that attach to the 50 amp
> ribbon fuse (D) and it was very hot while running the engine with AC
> on. The middle relay (B) was quite warm to the touch. So I pulled the
> 3 relays and tested them by putting 12 volts across terminals 85 & 86
> to trigger the relay (on relays A & B). Those 2 relays seemed to test
> fine and the digital meter showed continuity on the switching
> terminals. But the larger relay (C) looks to have 2 relays inside. The
> diagram shows terminals #2 and #5 will trigger one relay (it did not
> trigger) and #1 and #3 trigger another (it was triggering).
>
> So, am I testing the relay properly and if so, does that mean the #1/3
> relay is bad? If there is anyone on the list who has the relay in
> question out of the van to see if it tests the same as mine? Am I
> missing something?
>
> Thanks in advance!
>
> Keith
> 90 Westy Syncro
>
> PS Since I get digest mode, please CC me via pmail as well.