2008 Prius will NOT move + Code P0A90 Drive Motor “A” Performance

So I was watching a video last night on youtube where a guy takes the engine out (from the top) without removing the inverter or trans and it took them less than 2 hours. I was wondering if it may be worth taking the engine out instead to get to the damper rather than removing transmission since its apparently harder since it comes out the bottom and seen you have to remove the subframe.

 

I just ordered myself a Autel AP200, I hope it works as I am very disappointed my $1700 scanner couldnt do what an apparent $50 scanner will. BTW, yes it is currently $49.99 on sale at the moment if you have Prime on Amazon, down $10 from original price of $59.99

 

Update:

I removed the transmission today and gotta say It was quite a task but easier than other cars. I was surprised to see the damper intact as well as the other end of the transmission had NO grind marks. I could have sworn the grinding noise was the damper plate springs that were broken. One thing I did notice is the transmission had what appear to be “hairline cracks”, I am not sure if they’re actual cracks or the casting is that way but the replacement transmission has a smooth face. I did notice the damper spring clips had some very slight play. I am concerned about removing it as according to LAM’s trans removal guide on here says the bolts are hard to torque the last 90 degrees and there is no alignment tool to reinstall it.

Do you guys think I should remove the damper? I am leaning 80% to doing so as I do have a used replacement and really want to see behind it of there is anything broken there. Its just the re-torquing and installation im fearing now. If removed, can it go in any way or is it like a timing belt that needs to be set at a certain position before removing? I have NOT found any videos online or guides on how to replace the damper so want to make sure before I do it.

Here are the photos, If you see the last few of the part with the output shaft and perhaps zoom in around it, that is where the hariline cracks are. They are more prominent in the last photo before I cleaned it with brake cleaner :

 

A grinding noise isn't even a kind of noise you'd typically associate with the damper. According to 2 videos that can be found on youtube a grinding noise is a possible sound that happens when the springs on the outer clutch-like plate break off as they will grind with the rotation of the plate hence creating the “roughed up scratches” on the trans side videos have shown (not sure what to call that wall, where mine has the hairline cracks). If the coil springs get busted out of it, it will make a hammer-banging noise as it bangs to one end then the other of the travel that the springs were there to limit. And even when it does that, it likely isn't the culprit, but a casualty of some other problem that had been causing an engine misfire for too long. The car did NOT have any misfires prior to the issue with the noise. I put a stethoscope and grinding noise was coming from the trans side. Now that the trans is out and I do not see any physical damage other than what I mentioned that appears to look like hairline cracks, I may just need to open it up and inspect the planetary gears and chain. Also, for how common you say it is, when doing a search on here, there is no specific information about it that I found that would assist me with the P0A90 along with the grinding noise I was having. If you could kindly share a link to one of the posts where someone replaces the damper or has done other troubleshooting for a grinding noise in the trans, I would appreciate it.

Now that you have the transmission out, if you grab the input shaft and turn it, what do you hear/feel? Nothing out of the ordinary, spins freely.

How about when sticking some axle shafts into the output splines and turning those? Same, nothing out of ordinary.

The trouble code you have pertains to the performance of MG2, and might be related. Correct, I was unable to find the sub code (3 digit after P0A90) as none of my scanners would give it and when I finally got one that did (AP200), the code would not come up without me turning the car on and leaving it on for a while and with the grinding noise I couldnt do that.

Finally, Thank you for chiming in on this!

 

Also, forgot to mention that the longer cv axle from the passenger side came apart from the trans side when trying to remover it. The boot came off and i ended up just removing the axle and leaving the head in the transmission. With this being said, can this be rebuilt by me at home or are they no longer good once they come apart? I figured they just needed a clean up and a re grease but not sure.

 

The axle felt pretty solid with spongy movement unlike others I've felt that are limp. I figured a repack of grease would fix it but not sure which is why I asked. So which specific grease should I buy and try to repack? Poly Urea?

 

I finally found a video showing the exact same noise coming from the same place as mine and everything is identical (dirty black smelly oil), code p0A90 along with a P0335 crankshaft pos sensor code. Although in russian, this is the only video I found online of someone showing the sound, showing where its coming from and ultimately showing the location of the failure. This now gives me the confidence to perhaps leave the damper in and tear down the old transmission to see if I had the same failure inside the satellite gear (spline) or whatever that was called.

Guy eventually replaces the transmission and said the issue was resolved. WIll post results once I open it up. It will be a good donor to understand the inside of these transmissions more. If anyone wants to see anything specific inside it, this one is a good candidate to show just lmk.

Here is the video. If you click on CC and change from russian to english, you can at least read what the guy says.

 

SOLVED.

Well I eventually opened the bad transmission and upon initial inspection, all looked well and in place with only very DARK/BLACK Trans oil and foul smelling. When I went to put everything back together, I noticed the satellite gear top/cover was NOT sitting flush. Upon closer inspection I noticed the teeth on the cover were badly ground hence it would not go in and sit flush. I then spun the gears and sure enough, the grinding sound began. As the gears turned and the satellite cover/top stayed in place, it would produce the grinding sound and eventually began to eat the bottom portion of the teeth. Additionally, there is a washer with 3 “ears” that goes on the top of the cover that had 2 of the 3 lobes missing and I believe this helps hold the cover in place when all put together, so it could have been the culprit or collateral damage.

I have included photos and a video on youtube for others who may be experiencing similar issues as when I attempted to look up similar issues to mine (code, grinding sound and similar symptoms), I could only find 1 video and it is un Russian (thank God for CC translations).

Replacement transmission is going in next week, I am really not looking forward to the mating process but excited to see if my 1st transmission job is successful.

Thank you to all who shared their information.

Video:

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I am finally putting the transmission back into the car. I took advantage of everything being apart and replaced the spark plugs, pcv valve, cleaned injectors via ultrasonic cleaning, replaced both front strut assemblies, lubed all brake parts and replaced a broken stud, replaced inner/outer tie rods and boots, replacing nothing axles as these look pretty beat too.

Finally, I am going to wait on installing the transmission as it requires 2 people to get it aligned correctly and so far i have done all this on my own. Def need 2 people for the reinstallation, I am about 1/2 inch off to the left from aligning it but the transmission is to heavy to tilt it and push the trans jack forward.

Wish me luck, should post once im done.

ALSO, I replaced the clutch like part that goes on the damper that has (6) 12mm bolts and only thing I found online as far as torque was that of 15 ft/ lbs. Is that correct? Can anyone confirm this? I did not remove the inner pressure plate with the 12 point screws as it looked ok and no leaks so figured no need to replace the main seal.

 

Hey guys anyone here use BG 3143 ATF? I am getting a really good deal ($80) on a 3 gallon tub of it and apparently from a friend who works at Lexus. He said that is what they use on all their ATF WS applications as they are the same as Toyota. I just cannot find much info on it online about it being compatible with the prius ATF WS.

Can anyone confirm this? I believe the 3143 P/N is only for the 3 gal tub the 1 qt is 31432. This is from BG site but nothing on what it is compatible with or at least i dont see it:

https://www.bgprod.com/catalog/transmission/bg-full-synthetic-atf/#Specificationsins_tab

 

UPDATE: Finally finished the project. Installed it all back together and car is back up, started great and moves back and forth, I just cant test drive it as I replaced all the front end components and need an alignment first.

The one thing I did notice is that the battery shows at 2 bars under full and has only gone down 1 bar since I have been testing it out. Also has a red car with exclamation mark and says “problem” where it normally says ENERGY in the power distribution screen. Any idea what that is? I scanned the car and currently does not have a check engine light on but that could be because of the recent 12v battery installation.

I am seeing some codes that I cannot delete with the AP200 scan tool and what appears to be old codes so not sure which are current and which are old as they do not delete with the tool.
:
C1241 Low Battery Voltage or Abnormally High Battery Positive Charge
C1256 Accumulator Low Pressure
C1378 Capacitor Comm Malfunction
U0293 Lost Comm with Hybrid Vehicle Control System
C2121 Cannot Receive data from the Transmitter id1 (main)
C2124 Cannot Receive data from the Transmitter id4 (main)
C2179 Tire Pressure ECU Communication Stop
P0A2D Drive Motor A temperature sensor circuit high
B1271 Combo Meter ECU Comm Stop (this may be due to the combo meter not working im sure)
B1421 Solar Sensor Circuit (Pass Side)

 

These are the ones that show CURRENT:

C1310
C1378
C2121
C2124
C2179
U0293
B1271

P0A2D also shows current and “History”

Part of the work up to for the P0A2D code is to check the wiring for the “Motor Temperature Sensor” for any damage BUT, I cannot seem to find it. When googling the location, I only get “Engine Coolant Sensor” location which appears to be different from the Motor Temp Sensor.

I found these photos but the location appears to be conflicting, See below. Also, I am very concerned as the work up to the situation if it is in fact the “Temp Sensor”, that is inside the transaxle and cannot be replaced without replacing the transmission WHICH I JUST DID. So that is somewhat alarming even the thought that that piece may be bad and requires transmission replacement AGAIN. The P0A2D did not come on before the transmission replacement as you can read in my description title and was only getting a P0A90 and P0335, which are no longer showing up.

I am solely using the AP200 to read the codes and try to delete them, should I try a different scanner to attempt to delete? I am aware that some codes need a native scan tool or software like techstream to delete but most of the time, deleting thim is successful thru any scanner even thought they come back immediately.

 

UPDATE:

Well to my bittersweet advantage, I looked at the motor temp sensor 1 in the first image on post #58 and found the RED wire to be cut or out of the connector socket which most likely happened while initial removal of the connector and the tug of it. This is exactly as another PC user reported to his advantage as causing his P0A2D code as well and apparently reconnecting worked. It is late here in CA and now dark so should work on removing the plug pin and reconnecting it to the socket.






Luckily, I have my old transmission open and I am able to post for you guys what the inside of the transaxle that houses the Motor Temperature Switch looks like and WHY it is not replaceable nor serviceable. Now, the actual plug/switch itself IS replaceable but NOT the temp sensor probe as it is held on by a 10mm bolt next to the stator to obtain temp readings and the second wire is attached to the stator itself hence it is not replaceable without opening the transaxle. Another thing to take note that the MG2 houses ATF so I am assuming that removal of just the exterior switch itself would cause ATF to leak out. Please see photos below for reference.



I will post results once I reconnect the wire back to the socket. Hopeful!