Keeps going into Traction battery protection.

My wife was driving our 2012 Prius and got the Check Hybrid System warning as soon as she hit the freeway. I went to go check it out and when I started the car, after about 30-60 seconds, I got the message "Traction Battery Protection Mode. Restart while in Park." I restarted and attempted to drive it after looking up something that basically said it needs to charge the battery. I crawled forward for about 30 seconds before the same thing happened. Keeping in mind that it wasn't in neutral at any point before, or during this.

I know that it is possible that the battery is going out or, if I'm lucky, maybe that the battery fan is clogged and just needs cleaned. Are there any other possibilities that I should look into. I'm trying to go balance easiest and most likely to work on first.\

Also, sorry if this has been asked a hundred times already, but most of the forums I've found about it involved it being in neutral, but mine is happening while in park or drive.

 

It was, and still is at one bar, or 2 then drops quickly down to one. After several hours, it stopped saying traction battery control and went back to just saying check hybrid system. I got the yellow triangle, but no codes on my standard OBD reader. I don't have one that can read hybrid codes.

I put 4 gallons of gas in, just in case it was a fuel gauge malfunction which I had read about, but that didn't change anything.

I haven't tried just leaving it in part, because even at one bar, the ICE isn't kicking on to charge the battery and I was afraid of running it even lower.

As of now, when i turn it on, it starts to rev for just a second, then just coasts down to nothing. Kind of like when you turn a fan on then turn it right back off.

The other thing I've done so far is check the HV battery fan. It was already pretty clean but I went ahead and cleaned it a bit more, then I started the car when I could see the fan, and the fan seems to be functioning properly.

 

Yes but unfortunately, cheaper code readers don't seem to be able to pull codes related to the hybrid battery system. I'm hoping it isn't the battery, but it very well could be.

I am hesitant to assume it is the battery being the issue though, because i've had the check hybrid system come on about a year ago, and it ended up being due to a head gasket leak causing a bunch of issues with the system.

 

Yes the intake grille is clean.

And no, the car is not in neutral unless there is also a common problem of it being in neutral randomly, despite saying it is in park or drive.

 

Update: After trying to start the car several times, it kept spinning up for a second on intial startup, then just stopping. It shows the READY signal on my dash with no hybrid warnings unless I let it sit like that for a few minutes (after which the traction battery protection will kick on or sometimes it is the check hybrid system warning.. The ICE doesn't kick on to charge the battery.

If I shift into drive and hit the gas, it just starts rolling backward as if I were in neutral (but to be clear, I am definitely not in neutral), so it has no power going to the engine at all that I can tell.

I did finally get a P0335 OBD2 code, which is "Crankshaft Position Sensor A Circuit".

 

I ordered a reader and it should come in tomorrow. I guess it isn't a matter of quality necessarily, it is more bluetooth compatibility that was the issue so I can use the Dr. Prius app.

As far as the fan goes, it does spin properly, both before and during the warning coming on the display. I checked the intake and exhaust piece goes into the battery and they are fully open and undamaged.

I am also suspecting it might be a tradition ICE problem, but what is throwing me is that my OBD2 always reads normal ICE codes on both of my cars. I've only had problems when I get the hybrid system warnings, but it isn't really pulling any codes (other than the P0335 that I am looking into now).

Is it possible that it is the MG1 not allowing the ICE to start? I know that one of the main components for a car to start is the starter which happens to be the MG1 and my wife did say she hit a particularly large pothole the day before and I'm not sure how much of a risk there is in damaging a transaxle component, or if it is pretty safe up there.

 

Also, the main reason I tried to start it a few times was in hopes that it was just bone dry and had a fuel gauge malfunction and that maybe it would require a few attempts after putting in gas to get it started. I think that was not the problem.

 

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Hmmm...I wonder. Which is why I said I was looking into it. If you had read the full post, that code was not there originally and I had to start the car several times before that code was pulled. Thank you for your very helpful input though.

 

So my bluetooth tester came in today. The codes that were pulled were the P0335, P3000 and P0A0F (which seems to be the generic failed to start code). My app isn't giving me a specific sub code of the P3000.

I also inspected the CKS, and it looks fine as far as wiring and connection. I removed it and tested resistance across the sensor itself which read about what I would expect. I also checked that one of the harness wires is properly grounded, but my DMM is the most accurate when it comes to low voltages, so testing for voltage on either the sensor or the connector wasn't particularly helpful to me.