The other day my 2nd gen Prius ran a little rough before idling down and kicking off. All the lights on the dash flicked on and the the two codes P0016 and P0345 popped up on the scanner. I would like to check the camshaft position sensor but it was such a pain to get to I figured I would ask around first. Any advice or information would be helpful! - Woods
Are you absolutely sure that was a P0345? What scan tool was used to read it? I ask because all P0 codes are standardized by SAE, and P0345 is a camshaft position sensor for bank 2, and a Prius engine is a single inline-four that hasn't got any bank 2. I've just searched a PDF of a Gen 2 repair manual for P0345 and it was not in there anywhere. P0340 and P0341 are valid Prius codes. P0341 marks a problem with the camshaft sensor for bank 1 (the only bank there is). P0016 reports that the crankshaft and camshaft position sensor readings don't correlate as they should. When both sensors are trustworthy, that could indicate a serious mechanical issue, like the timing chain having jumped a tooth. However, if you are getting some code that makes the camshaft sensor look questionable, I would follow up on that first.
Depending on what scantool the OP has, he might have a P0343 - cam sensor signal erratic (?) in the hybrid control ecu. Posted via the PriusChat mobile app.
Ok, one of those is a P0354 (the expected confirmation pulse IGF is not coming back from ignition coil #4), and the other two are P0343 (an issue with crank/cam timing signals reaching the hybrid-vehicle ECU), and P0A0F (the hybrid-vehicle ECU saying "not sure what just happened, but the engine didn't start"). The HV ECU is kind of the orchestra conductor for the car. It gets information from the engine's ECU in a couple different ways. (Is that Carista you're using? Peculiar that it calls these last two codes "battery codes". Does it just think any code from the hybrid-vehicle ECU is a battery code? These have nothing to do with the battery.) The engine's ECU sends readings like engine RPM to the HV ECU as messages over the CAN bus, but also there are two circuits connecting the two ECUs directly and carrying pulse trains derived from the crank and cam. Those two circuits have mnemonics NEO and GO. The P0343 code indicates a problem with the GO circuit. From the waveform pictures in the manual, it should have about a 10 Hz square wave, measured at the HV ECU from GO to ground, when the engine is idling. (That's 600 cycles per minute, which is roughly half the engine idle RPM, so I'm guessing one GO cycle corresponds to one cam rev.) The signal swings from battery voltage to slightly above ground. The NEO signal is a little different; its swing is 5 V rather than battery voltage, it's a narrower pulse (longer gnd than 5V), and looks like about 300 Hz at idle, or 15ish cycles per crank rev if my arithmetic is right. Probably derived in some way from the crank sensor teeth. I mention it here just for completeness; you don't have P0338, which would be the code for a NEO issue. The code you have is about GO. If the HV ECU detects these signals are electrically wonky, it sets these codes. (It can also set other codes if the waveforms here indicate a different engine speed than what the ECM is sending over CAN.)
If there is a (total) loss of IGF from any coil then the ECM will kill the engine. Seemed to be a weird operating strategy that Toyota had in that era. Thus the ICE no start code. Posted via the PriusChat mobile app.
I grabbed a capture from my 06. Top is GO, then CMP, NEO and CKP. Posted via the PriusChat mobile app.
Hmm, am I reading your capture right, is NEO also swinging between ground and battery voltage? Looking at the picture in the manual, I thought NEO had a five volt swing. Maybe the picture's mislabeled, or I just misread it.
Nope, both signals are 0 - 14V (battery) squarewaves. The corners are rounded, probably have some capacitance on the circuits to keep the noise down. CKP is a 36 minus 2 pattern, while NEO looks like a 12 minus 3/4? Posted via the PriusChat mobile app.