On Fri, Nov 20, 2009 at 2:02 PM, David Beierl <dbeierl@attglobal.net> wrote:
> At 04:33 PM 11/20/2009, neil n wrote:
....

> Internally I imagine it runs on 12.0 +/- 0.5 and 5.0 +/- 0.25 volts,
> although it's possible that the 12v part could be running at the van system
> voltage. �It can undoubtedly tolerate supply voltages of +16 volts, maybe
> more, at least briefly. �One thing it *won't* be happy about is unhooking FI
> or ignition driver outputs while it's running (damage can be invisible and
> cumulative, btw), and undoubtedly some or all of its pins are
> static-sensitive when not connected into the van wiring.

Thanks David. Interesting point re: cumulative and invisible damage.

So there's obviously something in the ECU circuitry that regulates
and/or protects the voltage sensitive components from damage (within
reason). Something similar to the Vanagon voltage stabilzer on the
instrument cluster foil.

I have an air cooled Vanagon ECU. Maybe I'll pop off the cover and
have a look-see. Much simpler I'm sure, so maybe there's an obvious
component visible.

Neil.

-- 
Neil Nicholson '81 VanaJetta 2.0 "Jaco"

http://tubaneil.googlepages.com/

http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-engines