In the 2wd 2.1 models the temp gauge sender is mounted in a plastic
housing that is bolted to the head and presumably would not give as
valid a reading if there was no more coolant flowing through the
housing. In Syncros the housing is metal.

In any case the low coolant level warning circuit is supposed to help
prevent engine damage by flashing the led when just a little coolant has
been lost. The system holds a lot and can cool fine with a quart or 2
missing for a short while.

The importance of properly working dash instruments cannot be over
emphasized. I have worked on MANY Vanagons where someone had disabled a
dash warning system rather than fix the problem that was causing the
warning to occur.

Mark

Don in North Carolina wrote:

> Aaron,
>
> It is the overheating that kills the engine.  Unfortunately, once the
> coolant is gone, the temperature sensor has no way of knowing what the
> temperature of the engine is, since air doesn't conduct heat as well
> as the
> coolant!  So even if your gauge reads normal, you can overheat the engine
> and destroy it with no indications of problems (other than the load
> noises
> it may start to make), that is why a sudden catastrophic loss of
> coolant is
> such a bad thing, and why you need to pull over and shutdown as soon
> as it
> happens.
>
> The coolant tank level sensor is supposed to warn you of this issue,
> but in
> my experience it doesn't work very well at this - be warned!