A/C then inverter coolant pump

check the reservoir for movement

 

Yes, there is often confusion when people have AC problems and then get a coolant error code. But they are two seperate systems... P0A93 is usually a small electric pump that is the most common thing to fail. It's fairly close to a beginner's level repair job if you or a friend want to save anywhere from few hundred bucks on repair from a reputable local mechanic or $600+ from a Toyota Stealership.

As @bisco says the first step is to see if the coolant is still moving in the reservoir on right side of engine compartment. If it is then the pump is still working. Beyond that we can tell you what you need to know once you tell us what you want to do.

 

One possible connection to keep in mind is that the inverter is what powers the A/C compressor in Gen 2.

If a problem with the inverter cooling pump leaves the inverter overheating, the inverter will protect itself by interrupting power to the A/C.

 

Yes, but then they would realize they had a problem with the inverter at the same time they had a problem with the AC and OP says the AC problem came first.

 

From the original post, I've got an open mind on the exact timing between noticing the A/C issue and noticing the P0A93.

The inverter assembly has a few separate bits of electronics in it; the inverter for MG1, the inverter for MG2, the boost converter, the A/C inverter, and the DC/DC converter. When the temperature is rising, my understanding is that they don't all have to shut down together.

 

My air conditioner stopped working a while back. Worked in the morning on the way to work. Didn't work on the way home.

A classic early sign of the inverter cooling water pump failing. Intermittent AC. As mentioned, a warm inverter will protect itself by cutting off the power it supplies for the AC compressor.

As always, FIX THE OBVIOUS FIRST. Replace the pump. It should be replaced about every 80-100k miles anyway just for peace of mind.

 

Interesting, you'd think that if the inverter starts running hot and reduces power to the AC that there would be some kind of error code?

 

Maybe

 

You are making too much sense. And I agree, there should be. Unfortunately, I see these symptoms almost every time I do a pump. If I don't ask about it ahead of time, I can't tell you how many times I've gotten the "after you're done with the pump, can you look at my AC?" .

So far, the intermittent AC problems have always been solved by the pump replacement.

 

possibly

 

tantalizingly

 

Just to chime in: I hadn’t especially noticed an issue with my AC, but after replacing the inverter coolant pump last week, I have to say that the AC feels ice-cold amazing. Definitely a major improvement there.