Code reader can cause U0293 and other communication issues.

So the check engine light went on on my 2007 Prius,and I bought a code reader to determine the problem. The inverter water pump had failed, so I bought one and installed it myself. However, all of a sudden there were new codes being thrown along with the red triangle. UO293, U0100 primarily. The car would die and and the gear box would flash.

I spent nearly a week pouring over potential issues, checking fuses, wires, etc etc. I was about ready to give up, so I did a mental checklist of everything that I might have touched or messed with after the original inverter water pump code that was no longer there because I fixed it. The only new variable was the code reader itself. Because I knew it was an information issue, on a hunch, I cleared the codes and quickly pulled the reader out after the lights went back to normal. I restarted the car, and the problem is gone. The code reader was actually causing the codes.

Anyway, I just signed up and figured I’d share this because this forum has been such a help to me. I’m in between jobs and my little Prius is keeping food on the table VIA Lyft and I couldn’t aford expensive repairs and I was loosing work.

I’m very happy for the help, and I wanted to do my part if someone else finds themselves in this problem. Thanks

 

Thanks, yeah I charged the battery and ran a volt meter across it. It did shows a 12.71 or so, and the the check engine light would be on, I’d clear the codes and the car would run for 10 minutes or so before stalling and throwing all the codes.

After taking it out, (It’s blue tooth to an app reader) everything is fine now. I drove it all evening just to be sure. I do hear you, and I’m going to replace the battery anyway, just Incase. Thanks for your input.

 

Yeah looking back the other codes literally started right when I was trying to figure out the other issue was (inverter pump), it’s what lead me discover the actual problem. I did not have an intention of leaving it in, but I was just trying different things, and clearing the codes to see if it were the problem, so the reader was in a lot. I had no idea that it could be the problem itself.