'91 200q turbo cooling pump question

[Phil@sievers.com (Phil Payne)]

In message <199703250651.WAA27368@cosmoslink.net> "Meron" writes:

> > Is it thermostatically run?
>
> <No.  It's a timer.
>
> Check other posts (today), it is controlled by a temperature sending
> unit.....

Well, as I posted elsewhere, it ain't necessarily that simple.

The radiator and injector cooling fans are simple circuits:
Thermoswitch ==> relay ==> motor.  Certainly on the MB, the turbo
coolant pump doesn't work like that - controller J155 is in the way,
between the switch and relay.  On the MB, the test sequence is:

a) Bridge thermoswitch.  Nothing should happen.

b) Start and stop engine.  Nothing should happen.

c) Wait a minute or so.  The turbo coolant pump should run.

It might be different on the 200T.  Individual 200Ts might be different
from each other.

But if you bridge the switch and the motor doesn't run - try the above
extended test.

--
 Phil Payne

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