Date:         Thu, 14 Nov 2013 14:14:25 -0800
Reply-To:     Tom Carchrae <tom@CARCHRAE.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Tom Carchrae <tom@CARCHRAE.NET>
Subject:      Re: Arduino and Vanagons
Comments: To: Neil N <musomuso@gmail.com>
In-Reply-To:  <CAB2RwfjCnMLKHbgYko+8HGoryE4oX=EPNcRcKwVF+a4Fiuv63w@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1

Another WAG;  the power steering pump, etc (which is not on my van) are
probably to avoid low engine revs before they happen.  Perhaps the impact
on engine speed happens so quickly that they need to pre-empt it by
checking sooner?

That board does not look too bad - no custom PLC or IC evident.  Those
chips are just amplifiers http://www.futurlec.com/Linear/LM2902N.shtml

Tom




On Thu, Nov 14, 2013 at 2:09 PM, Neil N <musomuso@gmail.com> wrote:

> This is a WAG but is it b/c the ICU is only using hall input as a
> measure of a running engine and no more? And-or the ICU will react and
> control the idle stab. valve faster using switches than it would using
> engine RPM drop as a reference? Interesting question though.
>
> Mark: Thanks. The guts of the ICU look fairly involved (though I
> appreciate that the electronics are somewhat old school given that
> IC's aside, you can actually see all the caps, resistors etc.)
>
> image
>
> http://images.thesamba.com/vw/gallery/pix/1111642.jpg
>
> Neil.
>
> On 11/14/13, Brett Ne <brettn777@gmail.com> wrote:
>
> > Okay, now it's time for a dumb question: why do we need input signals
> from
> > the power steering pump and air conditioner?
>
>
>
> --
> Neil n
>
> Blog: tubaneil.blogspot.ca
>
> '88 Westy http://tinyurl.com/c8rlw6p
>
> '81 VanaJetta 2.0 "Jaco"  http://tubaneil.googlepages.com/
>
> Vanagon VAG *Gas* inline-VR Engine Swap Group:
>
> http://tinyurl.com/d7gd5ej
>