Keeps blowing water pumps, 3rd water pump, code p261b

Wondering if this was figured out.

 

I'm on my fourth water pump in a year. latest p261b just happened on a 2 month old oem aisin pump...wondering if there is a know recall or defect. i have to assume a bad ecm at this point...any other ideas. literally everything else has been tested

 

I'd be curious whether the three pumps actually got 'blown' or if they'd have worked ok on a bench test before and after and the code is being reported for some reason besides the pump.

(For any prolonged bench test of a pump, you'd need to somehow mount it and supply it with coolant to pump.)

When you say "OEM Aisin pump", do you mean one that you bought from Toyota and was made by Aisin, or one that was made by Aisin intending to sell to Toyota but they changed their minds and ground off the Toyota logo and sold it to you?

 

Any electrical harness or connector damage and has anyone ever dumped anything other than coolant into the system. Has the cooling system ever been flushed? Are you monitoring the ECT in real time?