Pardon the cross-post to both Vanagon and Diesel-Vanagon lists....

Having previously owned only 86+ vans, I am learning about some of the
differences between my '82 diesel and later vans.

When I got it last fall, my '82 had the old-style coolant reservoir. It
had no level sensor, but there was what appeared to be an electrical
connector for one, i.e. it had right kind of two-contact plug, it was
not connected to anything, and it was routed to the general vicinity of
the reservoir.

I upgraded to a TD engine over the winter, and in the process, installed
the later style reservoir with a level sensor. I also upgraded to a
later style instrument panel w/tach (from a european TD) and rewired
accordingly. The coolant light does the usual "blink for a few seconds
then go out" thing when I turn the key on, but if I unplug the level
sensor to test the light, it does NOT start blinking. The temp gauge -
and all the other lights and gauges - function normally.

There is only one wire - #6 - in the instrument panel connector for the
coolant temp... so how does both the temperature and the coolant level
status get tramsmitted through the same wire? Was the unused connector
really for something other than a non-existent coolant level sensor? Is
there some control unit between the sensors and the instrument panel
that I don't know about? Has anyone else experienced this?

Thanks,
Doug Fitz-Randolph
Freeport, ME