2001 Prius (242,044 miles) with transaxle error code! Red triangle with exclamation mark, check engine light, PS error, Main battery error, and little red car with exclamation mark error. One week ago car gave random misfire codes with a burnt smell... could have been from my car or could have been a smell from the car next to me. Cleared codes and they never came back. This week I get the CODE OF TRANSMISSION DEATH the dreaded P3120 along with a 5 minute wait by the side of the road until I could restart it and drive the 5 miles back to the house. Cleared the code but it came back the next day with another total loss of power and another 5 minute wait on the side of the road. After I turn off the car and wait a few minutes it will usually start back up and I can continue on my way... sometimes for a few miles and sometimes for 10 miles. My question is this... could this problem be something other than a bad transmission (transaxle) or should I be looking for a used transmission on ebay? I have also heard that it is possible that the MG2 might be bad and that it can be swapped out without pulling the motor so how can I test and confirm my real problem. I plan to repair myself one way or another... Other than all these warning codes and exclamation mark warnings symbols she drives great until she stops producing power and coasts to a total stop.
Welcome aboard. Sorry to read your troubles. First, what kind of reader/scanner are you using? Is it Prius specific or generic OBD2 reader. The reason I ask there may be other codes your are not seeing. Jim
Yep, she's a peach alright. I have no idea, but my guess is that your problems manifest from having a 15 year old Prius with over 240,000 miles on it. Good Luck. If you have the skills I have no doubt you'll keep her on the road.
I have a regular old generic OBD2 reader. It seems like the car runs fine up to about 40 mph but if I push it past that it will start groaning and struggling and then eventually die... after about 5 minutes of cooling off it will restart and drive away. The next time I get in the car the codes and check engine warning is usually gone but I know if I push it past 40 mph it will shut down again guaranteed. very STRANGE ISSUE... The 12 volt battery tested fine. I don't think it is out of the question to expect 300,000 miles out of this little baby... try that with a Chevrolet! I am just looking for some tips on where to start testing to narrow down the little gremlin that is chewing on my wiring or transaxle coil.
I'm at work so I don't have my manuals handy. But next best is the Yahoo Group, "Prius Technical Stuff": Yahoo! Groups I followed the quick start guide to plug it into the Prius, connected the battery, communication started and (as expected) no codes were found due to the absence of battery. Then I started the car, let it do its clunk-----clunk and restarted the tester. It found one code: P3120 HV Transaxle Assy Well, it was expected that it would report something like that but I could not find any sub-codes to get more detail. The "enhanced" Toyota display of the tester reported that no enhanced codes were found so this is all the info I have. I will probably need to wait to get more info until we have time to swap engine and then disect the old engine - unless someone wants to buy it, then we can just peer through the plug holes if something obvious has happened... I do plan to sell the transaxle and inverter unless I can find a better use for it myself... We really need miniVCI metrics but I'm OK if you want to get a full readout from the Toyota service center. But a couple of questions: Do you hear a hum/rumble whose frequency varies by the speed? If you shift into "N" (turns off the power electronics), does the rumble remain? Can you make a video/audio recording with the speed? I am most interested in three temperatures: ICE coolant temperature MG1 temperature MG2 temeprature In a healthy Prius, the ratios are: ICE > MG1 > MG2 In an unhealthly Prius transaxle: MG2> MG1 and ICE I need to explain that MG2 is on the end of the engine-transaxle stack and though it has a coolant channel, the bulk of its cooling is ambient air (and there is a LOT!) When there is a stator short, it becomes a default generator coupled to the spinning rotor of MG2. It generates power that the short converts to heat. It is the spinning rotor that causes the heating. This exceeds the cooling capacity and there in lies the problem. One risk is the DC-to-DC converter is on the bottom of the power inverter and sits on top of MG2. It can easily be overheated leading to a 12V voltage supply problem and dead 12V battery. Bob Wilson
Wow, Dr Bob, that is some reply with one hand tied behind your back :-D OP, I suggest getting or borrowing a PRIUS aware scanner. Preferably the Mini VCI $20-60 on ebay or amazon, It includes the Toyota diagnostic program that will also read PRIUS underlying codes. My Generic OBD2 gave me a reading of P1636, but it was false,well sort of but it was misleading, Code does not exist in Toyota. Purchased the $22 Mini VCI, it showed P3006, P3000 but not P1636. Without the real error codes, you are flying blind.
I did not notice any new rumble or hum that changes with speed. No noise while in neutral, just a quiet coast. I can make a video/audio recording. The car sounds normal until it gets over 40-50 mph then it sounds like it is struggling and then it just cuts off the power to the pedal and coasts to a stop. After 3-5 minutes I can restart and drive off again as long as I stay below 40 mph. I will drop it off at Toyota tomorrow and get them to diagnose the issue. Will they normally show the temperatures that you need on the report that they give me or should I ask for this information up front? They are charging $79.00 to check it out. I will report back tomorrow with more details. I will try and get the sub-code(s) tomorrow from Toyota... I have heard of many problems with people trying to set-up the mini VCI and the software on different laptops.
For $79, insist on getting the print out. It should have all the readings you need. If they won't, ask to see the readout on their screen and take a pic Yes, some are experiencing trouble with the loading of the TIS Mini VCI driver to make it a standalone version. But it comes down to operator error in loading the program and/or using the wrong Operating System on their laptop. All or most MiniVCI's use 32 bit Windows XP or less version. The one on Ebay for $60 uses Windows 8.0+ and either 32 or 64 bit. The trick is not to open the TIS until the "standalone" Mini VCI driver program is copied and pasted in the the TIS program. Your PC may ask if you want to copy an older version of the program, answer is YES, this will make it a standalone.
Did you check the inverter coolant tank to make sure the inverter pump is running? With the car on, the fluid level should appear split with visible motion if you take off the fill cap. Bob Wilson
Yes, the inverter pump is working. Just drove the Prius back home from Toyota appx. 7 miles of city driving with lots of traffic lights ... staying under 35mph and accelerating like an old lady to keep the car from shutting down and also to keep the error codes at bay. This is the results of their testing... "needs a HV Transaxle Assembly". Code read: P3120 Freeze frame data: Water temp meter 185F Engine RPM 4672 Vehicle speed 50 Intake air 79F Detail info 1: 241 Torque limiter sliding - Replace defective part inside the HV Transaxle Diagnostic Trouble Code Report: Code: C1259 - HV System Regenerative Malfunction - No freeze frame data available Any ideas???
C1259 is just a code from the brake computer saying "hey, go talk to the HV computer, it's got something to tell ya." P3120 inf 241 for a sliding torque limiter, plus a funny burnt smell, makes a perfectly consistent picture. That's the part that looks just like a manual tranny clutch but has no pedal to release it. The parts are shown here: 31270 and 31290 but as you can see there are various suffix numbers available, and this particular dealer diagram seems to have both parts listed under both numbers, something got mixed up. Anyway, looks like $300 to $600ish in parts depending on which prices are right. The daunting part is the labor. -Chap
