I'm baffled, I've got the infamous blinking light. It's an older Hot Springs/Watkins Sovereign model spa. I've jumped out pretty much everything to the point of getting the heater to work and all pumps run. The flow switch on the outlet of the heater never changes state. It has 10 - 11 ohms across it regardless of the pump being on or not. If you unplug the one on the inlet, it shuts everything down. Unplug the one on the outlet nothing. Circuit open, no change. Circuit shorted, no change. Switch in place, no change. Indicator lights on main circuit board are: Lim OK, on all the time; Heater on, off all the time; controls unplugged, off all the time; flow, on all the time. Relay to turn heater on never has votage to coil to energize it, so heater never comes on normally. I've tried to jumper the thermostat to see if I can get the heater on light to come on with no success. If I jumper the two outside terminals of the thermostat/rheostat, it's shuts the system down. Now for the thing I really don't understand. I'll have it running with the heater relay jumped out so heater is working. Total electrical pull is 13 - 14 amps and all of a sudden it trips a 20 amp breaker and never indicates a surge or anything. I even put a recorder on it and nothing. I figure maybe the high temp is taking it out because of no flow through heater/pump, but it shouldn't trip the breaker. I took it off the GFI, same result. I've moved to 4 different breakers and it trips all them after about 2 -4 minutes run time. Water level is good and main pump is pumping like crazy. Up until today, I thought I was fairly smart, not so much anymore. Ron

The lights you have on the IQ are correct except the flow light - if the spa is a 1997 then don't pay attention to the flow light. If it has an IQ2000 and dials instead of a digital control then it should be 1997. If it has a flow switch it is a 1995 or 1996. Some 1995,96 had the heater replaced from the cartridge type it had and the flow switch should have been jumped.
If you have good circ pump flow and the red power light flashes it may just be a high limit thermister problem (part #38416).