P0A93, Red Triangle of Death, and Christmas tree lights. Ugh.

As the title states I'm having problems with my 2004 Prius. It has 280K miles, driven fairly conservatively, and I do all the maintenance. This problem began a week ago and I'll try to explain the symptoms. Firstly I had the Brake and ((!)) light come on as I was slowing down for a red light at an intersection. I then tried to find an explaination. On the interwebs the first result which came back was a hybrid battery cell going bad. The next result said "check your fluid levels". So I popped the hood and checked all fluids. Everything was up to the full line. Then I drove it for a couple of days and on the second day after only about five miles the Red Triangle come on. Got to work and then came back home. Not too many miles on that round trip, only about twenty five. I got my code scanner out and it showed a P0A93 trouble code. Hmmm..what would cause that? Well, after getting on PriusChat I found that the main culprit to pop this code is a bad coolant pump. I ordered one from Amazon and it arrived a couple of days ago. I finally had the opportunity to install it this morning. Oddly enough I replaced it a couple of years ago, only after the original gave up the ghost. I did a visual check that the new pump was circulating coolant and it was. So, I then cleared the codes and even unplugged the 12v battery for a few minutes to reset its memory. Took a drive with my wife and after about ten miles the Brake light and the ((!)) warning light came back on.

This is where I'm asking the braintrust of Prius Chat to give me some guidance. Is there something else mechanically that I need to look at or could this problem arise from "maybe" an electrical relay going bad? Or should I take my battery module apart and test each cell for a good charge? I'd like to keep this car for a bit longer but if the fix is going to cost more than a replacement car then I'd opt for a different car.

I've seen guys on YouTube tearing apart their battery module and replacing cells, yet I don't like to play with live batteries. It's not beyond my capabilities, I just have a tremendous respect for electricity. Do y'all have any ideas? Thanks.

 

Max, thanks for the link. It's very helpful on how to track down what might be wrong. One question and I'm sure it has a simple answer. The two cooling fans, when will they come on? While idling in the driveway or will I have to run a few miles with the A/C on? Do they both come on at the same time or do they have different cycles? Thanks.