[s-cars] Manual Control of afterrun pump and fan

['Kevin Day']

On Mon, Sep 06, 2004 at 12:26:39PM -0400, Doug Landaeta wrote:
> Question: I thought that the after-run pump forces
> the coolant in the opposite direction than when
> the engine's internal water pump is running. If
> the standard after-run switch is by-passed, does
> the after-run pump and fan come on when the motor
> may be running? This may be a problem if the 2
> pumps are fighting each other.

In my arrangement, and I'm sure Sean's as well, the new hardware only
interfaces to the existing thermo-switch circuit.  The control unit in
the passenger footwell takes a signal from the switched side of the 
fuel pump relay, which it presumably uses to block activation of the 
pump and fan when the engine is running.  In boolean terms, 
(after-run system) = (thermo-switch) AND NOT (fuel pump).

-Kevin