Wife has a 2011 with roughly 190,000mi. A couple days ago it displayed "check hybrid system". I checked it with Dr Prius. It has p0343. If I check with my launch 70 Scan tool it says no codes. I don't have access to a pro level scan tool. I did swap in a good cam sensor from an unsuspecting visitors 2010 who happened to stop by. After clearing the code it returns as soon as the engine starts. Any suggestions?
The code means the signal received by the ECM from the sensor was 4.7 volts or higher, which is more than it should be, for at least four seconds. If it keeps coming right back, this is probably not some peekaboo intermittent issue, but something more consistent and easy to trace. If it isn't the sensor it could be in the wiring from the sensor. There are 11 pages of troubleshooting steps in the repair manual, but that's probably because they're covering P0340, P0342, and P0343. P0340 could indicate a wider range of problems; if there were a section for P0343 by itself, it could probably be a lot shorter.
The harness from the sensor to the ECM is only about a foot long (but probably 40 wires). I didn't see any obvious damage but that would likely give a code for a low voltage or open. That's what I was expecting as we have an abundance of chipmunks, and they just chewed the harness off of the prndl switch and O2 sensor on my pickup.
