quadroped

Hey yall, thought this was normal, guess not

my sai pump cycles on and off randomly while driving, I see my volt gauge dip down to 12 and it will stay on for a minute or so then turn off, 10 minutes of driving or an hour and a half of driving (summer)it always does it

now it stopped, code p0411, but the pump still kinda moans and in the ecu box there are no fuses, just the sai pump relay

my dead pump should have blown this fuse...but no fuse....kinda confused here

I think im looking at an engine coolant temperature sensor? there is only about 20000 on the current one, the sai pump has done this cycling since i bought the car 5 years ago, with the old ect sensor and aswell as the new one

just found out in my recent searches that the sai pump should only run when cold
im also wondering if I can get lucky at the junk yard with a pump from a vw or something...does anyone know what other vehicle pumps would fit?
any help on the troubleshooting would be greatly appreciated

Tony