2012 Prius refused to Start. Error Code P0335 – Crankshaft Position Sensor A Circuit Malfunction

Hi I can hear motor spinning for about 3 seconds then all shits down. chuba the original poster said his was a damper plate.

 

how many miles on her?

 

190k

 

10 plate with190k.

 

Not many really understand how things work or diagnostics. Almost everyone understands replacing stuff. So let 'em load up the parts cannon and stand clear.

Posted via the PriusChat mobile app.

 

If you really do hear the sound of MG1 spinning and you verify that the engine crankshaft is not turning when that happens, then those are the likely possibilities (except for naming: the shaft that connects the engine and transmission is the transmission input shaft).

MG1 turning without the engine is pretty powerful diagnostic information. About the only steps left are to get the transmission off and look for what broke.

 

If EGR hasn't been cleaned by 190K, maybe hydrolock from failing head gasket broke the damper? I'll put on my flame-proof suit now.

 

I have a similar situation with a P0335 code, along with a P0102 MAF sensor code. Did you end up finding the culprit?

Also, did your prius sound similar when trying to start?

 

With the P0335, the ECM is telling you that it doesn't have the signal saying the engine crankshaft is turning.

So you have a pretty clear Job #1, to find out if the engine crankshaft is turning.

Get somebody to push the button to start the car, while you are looking down at the balancer at the front of the engine (what would be the crank pulley on most other engines, only this one has no belt wrapped around it).

See if it spins while the car is trying to start.

If it does spin, then the problem is likely with the crank sensor or its wiring.

If it does not spin, then the crank sensor is telling the truth, and the problem is likely to be in the transmission, where something has broken and spins without spinning the engine.

So your first big question is which of those two situations you're in.

 

Thank you! I'll check it out.

 

Having the same issue, P0335. So mine is a little interesting, and would love help. So I got that rattle noise when started, ended up being the head gasket. Replaced that with timing chain, water pump, egr, plugs and wires. That fixed the rattling on start and occasionally at idle. After doing all that at 180k miles, I started to get the P0335 code only in the summer time. I have a 55 mile commute and it never gives me the code in the morning when it’s cool, but during the after noon ( just started giving it to me for the summer). It gives me that code and puts up all the codes and it goes in limp mode. Limp mode allows you to drive the battery down but the engine won’t come on to drive. I have found this occurs mostly when going up hill or driving around 40 minutes in the heat. Then I stall and go into limp mode, and I pull off on the side of the high way. I take my obII scanner and clear the P0335 code and it allows me to drive the car again and sometimes it’s good to get me the rest of the way home or sometime I have to do that 2-3 times. Again it has been doing this for 2 years now and only in the summer time. I am at 250k miles on my 2012 Prius V. Any suggestions or help would be greatly appreciated as this is my daily would like to not stall on my way home.

 

Hello! The crankshaft does not turn when trying to start the car. I just replaced the sensor with a new one (not OEM) to see if this would solve the problem but I get the same codes. Here is a video of what it sounds like when trying to start it:
Prius P0335 won't start - YouTube

I know you mentioned that this would mean the problem may be in the transmission... not sure if you get any better idea after viewing the video.

 

Well, as I kind of said earlier, if you have that code, either the sensor is telling the truth and the crank ain't turning, or the crank is turning and something is up with the sensor or wiring.

If you looked and saw the crank was not turning, then the sensor was telling the truth all along, and you probably didn't need to replace it, but ok, you've got a new sensor now (and the crank still ain't turning).

The transmission is what turns the crank, so as I also said in another post earlier in this thread, at this point about the only steps left are to get the transmission off and look for what broke.

 

Would rotating the crankshaft manually, while the car is jacked up in the front and in neutral, to see if the wheels rotate normally help determine whether the issue is with a component in the transmission?

 

No, because the transmission would be in neutral then (as it's effectively in neutral any time without winding currents) so you wouldn't expect motion of the crank to be transmitted to the wheels then anyway.

But the question at this point would have to be, what else are you expecting to find? The transmission is what turns the crank to start the engine, and the crank isn't getting turned.

Do you hear any whirring noise from the tranny at all during a start attempt? I mean, if you hear nothing at all, maybe you could be looking for some electrical or control issue. But if you press the button and hear MG1 spin and the crank doesn't, you've got something in pieces in there.

 

This is the most recent attempt at starting the vehicle: Prius P0335 won't start - YouTube
Hard to tell where the sound is coming from. I am going to try to order a mini VCI and try to see if I can gather more information about what is going on with the car upon startup. If no success, I may just have to tow it to the shop. Appreciate your feedback though.

 

There isn't any information left you need to gather. In your recording, you clearly hear MG1 spin up to cranking speed at 8.33 seconds in, and spin up super fast because there is no load on it, because it ain't turning the engine crankshaft, and in fact it takes several seconds to spin back down when the ECU gives up and stops trying to crank. Just a free-spinning rotor.

Dude, it's not turning the engine.

 

Pardon my ignorance, I'm a relative novice and am trying to sort through this information. So based on what you are saying, there is a mechanical failure somewhere in the transmission which not allowing mg1 to transfer any load onto the crankshaft and there is no way to identify this issue without pulling the whole transmission out and taking a look? The part that threw me off from the very beginning was that this occurred several days after I completed a bunch of tune-up work, but this seems to be completely unrelated.

 

Right. Regrettably, the aluminum used for the transmission case is the opaque kind, so it's hard to look in there. Either the transmission input damper, the input shaft, or the power split planetary gears will have busted, it seems. it won't have been the tune-up work.

Even if there were a way to find out which of those broke without transmission removal, there wouldn't be any access to fix it without transmission removal, so it isn't like extra work that could somehow be avoided.

While the input damper is sold on its own, I don't think any of the other internal Gen 3 transmission parts are (or not by Toyota, anyway); they would just replace the transmission.

 

Start Trek fan, perhaps?