Error codes on 2005 Prius I have a 2005 Prius. About a monthago, when I attempted to start it, it wouldn’t go into ready. There was a large red triangle with and exclamation point in it, check engine (not flashing), and I think the traction control light on on the dash. The gear indicators also had flashing boxes around them. Turned it off, then on. No change. Then I tried wiggling the shifter, no help. The. I tried starting it with the brake slammed down as hard as I could. This got the car started and in gear. The engine was making a thrumming noise. And the hybrid system wasn’t engaged( by the little power train graphics on the display). The car was very slow to get moving and would need get over 35mph. I went to an auto parts store and had it scanned and the battery checked. Here are the codes: POA1D - power train hybrid control module U0100 - lost communication with ECM/PCM U0111 - lost communication with battery energy control module “a” U0293 - Lost communication with hybrid Vehicle control system P0A1D - hybrid powertrain control module U0111 - lost communication with battery energy control module “a” (this one appeared twice) U0293 - Lost communication with hybrid Vehicle control system (this one appeared twice) The battery also tested bad. So I replace the battery and ask them to clear the codes. None of the codes go away. Employee says I would need a mechanic to clear them. Well none of the issues were fixed. So I brought it to a mechanic. They said the battery ecu and the hybrid battery were bad. So I brought it to a battery replacement place in town that specifically replaces Prius batteries. They said the battery was fine. So I went on to try to fix it myself. I replaced the hybrid ECM under the glove box. The car wouldn’t start. I found out I need to reprogram the immobilizer. That would be $250. So I put the old one back on and swapped out the battery ecu. this has an interesting effect. I needed to jump the car to start it. But it started more reliably than before. Still the hybrid system would not engage and when I shifted into park. The car died. Then it wouldn’t restart unless jumped. I’m stuck here. Should I put the new ECM back in and pay the locksmith to reprogram the immobilizer? I’ve also heard that it can be a grounding issue, but I can’t find a good diagram of the grounds I should check. Anyone have an issue like this before? Any advice?
You have network databus error codes. These can be THE most challenging to correctly diagnose and repair. There might be a failed module. There might be a problem with power, ground, or communication lines to that module. Loading up the parts cannon can get very expensive and often does not work. You need to understand how the databus systems function are put together. You need a capable scantool so that you can know what systems on the car can and cannot communicate. You need equipment to test the circuits involved. You have to do a bunch of self-educating, or find a really good shop. I do not know how capable FIXD is. Can you screen capture a "full system" scan for fault codes and post it? Posted via the PriusChat mobile app.
