The sensor (or actually temp switch) of this pump is located somewhere
between oil filter and the block ..when you open the lid of the engine
compartment you must see it.

The sensor is 107 �C (don't know at F).  You can identify the sensor by the
colors of the wires.  The sensor has two wires brown and brown/red while the
pump has red and brown/red.  There is also a relay enabling this additional
cooling in that plastic box (on the wall of the engine compartment).

I could check location of this sensor from my van but it is so cold out
there and it is much easier to give advices from here inside.  BTW I
couldn't found anything about this in Bentley ('cause this function hasn't
been in US models).

Juha Koivisto
'88 Vanagon (Caravelle) 1,6TD (old school bus with 9 seats)
TURKU, FINLAND