Diagnose A Jandy Lt Heater Control

[toucan58]

I posted long ago and never got even a nibble. My Jandy LT400 has no lights whatsoever on the Heater control panel. I tested the test points on the secondary side of the transformer and I get good voltages, both 24V and 12V for the common/red test point and the common/WY test point. I decided that the transformer is getting power and is outputting the correct voltage. I tested between common and test point 4 on the heater controller and I get 28V which is good. I tested the fireman's switch terminal block and all tests good. However the heater control has no light for either the spa or pool side and the heater itself just sits dead. I hate to just buy a $500 heater control card without being sure but if I am going to fix this myself it is the only option I have. Could anyone throw me a bone as to how to be better sure that the heater controller card is indeed bad? Either that or tell me I am silly for trying this myself.