Thanks man. I may have the thing fixed: I replaced the temp sensor and reprogrammed the controller, and it worked OK when I tested it. The question is, will I trust it?

Would you test whether your controller behaves the same as mine? With the motor cool and controller hooked up, though not necessarily "keyed up" (if you have yours connected to the ignition), disconnect your fan and see if you're seeing voltage on both the red and black wires from the controller. Mine does that reliably, and the ground to the controller is good.

BTW, what fan are you controlling with the SPAL?

Thanks,

Mark