Red triangle after replacing inverter coolant pump

Hi all, I tried to be a good PriusChat boy and use existing threads to fix a problem before creating a thread of my own, but alas, here we are. In short, red triangle flashed intermittently, I saw very little inverter coolant reservoir turbulence, I replaced the pump, and the triangle went away...until today.

She is currently at 226K miles and had a full hybrid battery replacement at around 200K. I haven't noticed any decrease in MPG. I got an oil change 500 miles ago. The red triangle and the word 'problem' appeared about a month ago for a few seconds when travelling over 50mph. It would flash and then disappear, and then reappear after a minute or so. A high heat symbol also appeared a couple of times with the triangle.

I went home and used my OBDII scanner and found no codes, but I am aware that these don't show every code or blink codes. I did some research and saw the inverter coolant pump is a common issue that could cause an inverter to overheat, so I replaced it even though I never had a P0A93 code. There was very little turbulence in the reservoir before the replacement and slightly improved movement after I replaced it with an AISAN pump. I bled the coolant system afterwards.

All has been well the last two weeks. No triangles, runs well, great MPG, absolutely nothing unusual. Sometimes the fan blowers and heat don't turn on but a couple kicks under glove compartment gets the blower motor groovin again. Today after about 20 minutes of driving the dread-inducing triangle began flashing again, again while I was at high speeds. A couple of times it stayed on longer than the other times and showed a high heat warning (see photo).

I am fairly novice with reading live data, but today immediately after the high heat warning was on my ECT read 90 degrees celcius, which is within a normal range. Any guidance here would be so welcome.

 

Both are at a healthy level

 

thanks for your reply. It does look like I need to add coolant to the radiator. After doing so do I need to bleed the system at all, or can I just let it run and monitor the level?

 

I added quite a lot of coolant in the radiator and refilled the reservoir. It is a bit concerning how much coolant was missing. I haven’t seen any leak, smelled any coolant, and my oil looks good. My rad cap doesn’t feel very springy at all so air may not be getting forced out, could that be the culprit?