I disconnected the auxilliary pump and then hot-wired the mono valve so that it is closed when the ignition switch is on (bypassing the controller). The controller now works fine operating the blower speed and A/C clutch.

Apparently the controller output to the aux pump and mono valve is fried from the high pump amps (2.45A).

Next step is to replace the controller and re-connect the mono valve (leaving the aux pump disconnected).

Later on, I'll flush the cooling system and replace the aux pump. I think the idea of an in-line fuse for the pump is a good one. I'll probably do that.

Does anyone out there see any problems with my approach?

Thanks in advance.

Brent Smith
Atlanta, GA