2016 - 2022 Toyota Prius Inverter with Converter

Hello, I am professor John Kelly and this is the  WeberAuto YouTube channel. Today we are continuing   our series on high voltage hybrid electronics  and we have an inverter converter assembly out   of a 2017 Toyota Prius eco that we purchased to  disassemble and get familiar with the inverter   converter assemblies on most Toyota hybrids are  serviceable meaning there are some internal parts   that you can change if there's a problem with  them rather than changing the entire inverter   converter assembly so let's get familiar with  some of the external features of the inverter   converter assembly here this would be the front  of the inverter converter versus the front of   the vehicle and there are two coolant hoses that  would connect right here this is a liquid-cooled   inverted converter unlike the Honda ones the the  honda IMA inverter converters that were behind the   back seats that we have a separate video on those  but we have one hose coming from the transmission   the transaxle itself the transaxle cooler which  is this bottom hose right here and then it goes   in and cools the dc-to-dc converter assembly in  the bottom of this inverter converter housing   and then it comes up through this black plastic  transfer pipe and goes in and cools all the IGBTs   the insulated gate bipolar transistors and then  comes out and goes to the coolant reservoir for   the electronics on this vehicle a word of warning  on these when you disconnect the hoses don't   disconnect these other pieces unless you are told  to do so because if you pull out some of these   plastic pieces at the wrong time before draining  the coolant out you can actually let coolant get   inside the inverter converter assembly in two  places where it should not be and then you've   got to replace the entire unit all right on the  top of the inverter converter as we can see here   there are two electrical connectors as part of  the removal procedure for the inverter converter   assembly we will disconnect the low-voltage  battery the 12-volt battery and on the   fourth-generation Prius that this is out of that  battery is up under the hood finally rather than   back in the back of the vehicle so we disconnect  the 12-volt battery we disconnect the little   service plug grip on the 207.2  volt lithium-ion battery that I have a   separate video on how to service that battery then  we disconnect these two electrical connectors here   now on the other side on the backside of the  transaxle here there are two more electrical   connectors we have one electrical connector here  that is from that connects to the air conditioning   system compressor so the electric air conditioning  system compressor this plugs in right here there's   two bolts that hold it down and you would need  to undo those bolts and pull this connector out   it has two mill terminals in the connector for the  air conditioning compressor then there's another   connector just like this except as two female  terminals rather than male and it is the long   16 foot to wire cable that goes all the way to the  lithium-ion battery in the back of the vehicle and   so the safe procedure for making sure that the  all the high voltage in this inverter converter   has been discharged is you will undo the two  bolts that hold the two-wire harness from the   battery you'll undo those and slide back this  electrical connector here and then you will put   a multimeter across there on volts of a voltmeter  and make sure that there's no voltage on these two   wires the if the contactors in the hybrid battery  Junction block are doing their job there will be   no voltage on there because the positive contactor  disconnects the positive terminal of this   connector the negative contactor disconnects the  negative terminal of the two wires that come up to   the inverter converter assembly so we've got two  electrical connectors in the back here one for the   high voltage battery one for the air conditioning  system and I'll have a separate video on hybrid   and electric air conditioning systems a little bit  later okay then on the side the driver's side of   the inverter converter assembly let me tip it  on its side here there's a great big electrical   connector that goes down to the p610 transaxle  and it has six wires the three two three-phase   sets of wires for mg 1 and mg 2 mg one is this  the starter in the generator mg 2 is the traction   motor that moves the vehicle down the road so  there'll be two sets of really short three-phase   cables that go from the inverter converter down to  the transaxle that's just right here below it this   inverter converter assembly bolts to the top of  the transaxle with a couple of brackets there's   also a high voltage interlock circuit here if  I pull off this tape right here and look down   inside we can see the six electrical connectors  for the motor-generator one and motor-generator   two but then right here in that little electro  electrical connector there's just two a two   wire connector that is the high voltage interlock  circuit that if you didn't disconnect the 12-volt   battery or the service grip service plug grip on  the high voltage battery when you unplug this it   opens the interlock circuit and the contactors our  shutoff anyway at that point just from unplugging   that that's an input to the hybrid battery control  module to shut off the contactors okay now there   is a cover on the top the cover on the bottom  and there's a seam between the upper and lower   housings on this inverter converter assembly all  three of those are sealed with the little form in   place gasket sealer it's gray out of the factory  it will be the black when you go back together   because apparently, they don't sell the gray to  you but in the service information there are   instructions on how to remove these covers without  bending them because this sealant is very it does   a very good job when everything is nice and clean  and dry when you put that sealant on there and the   right amount of sealant they call for a three  millimeter diameter bead of the sealant and   nothing more it makes a wonderful seal and it's  very difficult to remove if you're not careful   so obviously the first thing you would need to do  is to remove all of the bolts so I'm just going to   slow slowly back them out with my electric impact  here I'm not going to give it full throttle I'm   just going to back them out and slowly I'm going  to keep track of the bolts that go with the cover   here now there are some pride points where you  are supposed to come in with a pry bar and pry   up on this sealing surface now you have to be very  patient you can't just come in and give it a big   pry you have to come in and just tiny bit a pry  and then wait a little bit and wait a little bit   in eventually it'll break loose if it doesn't  break loose take a flat razor blade and slowly   start working it into the edge there and then it  will start breaking loose and when you're all done   you want to make sure that your cover is not all  bent up because it won't seal again afterwards   of course so I will keep the cover with the bolts  that it came out of now once this cover is removed   these two electrical connectors right here allow  the transaxle inputs and the data communication   and power and ground and so on from the rest of  the vehicle to connect to this circuit board right   here and the circuit board is called the motor  generator control computer and it is serviceable   but it's very delicate it's very you've got to be  very careful removing it so that you don't break   it during a removal and so that you don't break  the new one that you're going to put in and of   course these need to be reprogrammed once you put  them in so we have all of these little Phillips   head screws that have little rubber Isolators  underneath them and this red math that I have the   inverter convertor sitting on is an anti-static  mat it has a ground wire right here that I've got   clipped to a steel table leg over there and then  I'm going to wear a anti-static wrist strap here   as I remove this and install it so that I don't  cause an electrostatic discharge that damages   any of the circuits in the inverter converter okay  so I'm going to put on the wrist anti-static wrist   strap okay with the wrist strap on I'm ready  to start disassembly but there's one safety   precaution I forgot to do that I should have done  before taking this cover off and that is over here   on the side of the inverter converter we have  the two electrical terminals that were connected   to the high voltage battery those two terminals  inside of the inverter converter assembly here   connect to a number of things but one of them  is something called a big smoothing capacitor   and in parallel with this smoothing capacitor is  a resistor to discharge that smoothing capacitor   but it can take a few minutes to discharge  so if we take our multimeter and test it on   another battery or voltage source to make sure  that it's functioning the meter leads are good   and the multimeters functioning as it should  which it is then you can come in and measure the   voltage on those two terminals if you've waited  the amount of time that the service information   has told you to wait then this voltage should be  zero so we've this has been out of the car for   several months so it should be zero but let's  just go in here and touch both terminals zero   volts is what I'm reading and the capacitor is  fully discharged there's no danger of me getting   shocked doing anything internal on this thing now  technically I should have been worrying my high   voltage safety gloves at this point but I knew  that it was already discharged because I've had   this apart several times in preparation  for this video but in real life you need to have   those high voltage safety gloves on alright now to  remove the motor-generator control computer there   are let's see 20 one two three four five six  seven eight nine ten 11 12 13 14 15 16 17 18 19 there are 19 vibration dampening electrical  connectors on this circuit board these little   vibration dampening electrical connectors  need to be need to have their lock released   and they need to be lifted up now when I  first saw these I thought oh I can just   do that with a pocket screwdriver and I tried  on a few because I figured I'd I could do it   without the special service tool that it was  called for and I think I broke a couple of   the tops of the little unlocking tabs well  then I decided well I better get   the proper tool so this is the proper tool  this is a Toyota special service tool it is   part number 09905-0040 and this  tool is made specifically for coming in and pinching the lock tab and grabbing the inner  electrical connector and lifting up so I have   to do this on all 19 of these the new circuit  board by the way comes with new vibration   dampening connectors but you do not want to  loosen the bolts on the circuit board with or   the Phillips head screws on these without first  having undone all of these oh there's the 20th   one right there I thought there were 20 there's  20 on later model fourth generation Prius is like   2017 and there's pulled that one out too far  and there's 21 on earlier models so you want   to just pull up just slightly I pulled that way  too hard on the one and I'll have to be careful   and get it back in okay they are all loose  we want them to be able to lift up and down   and be free in their electrical connectors  and as I said I damaged a couple of them which makes it difficult to pull them back  out when they push back down they still make   a connection but they are more difficult to  pull out once you've damaged the little plastic   tab okay so I've got all twenty of the vibration  dampening electrical connectors loosened up so   now we will take out the Phillips head screws so  there is a rubber like a grommet and a flat ring   or a flat washer underneath it all of that  goes together with the rubber facing down okay so there are 12 of those Phillip head screws  with the little rubber I'm sure they're vibration   damper washers they're also then we have three  Phillips head screws that hold the electrical   connector of the circuit board to the aluminum  housing below it but this circuit this electrical   connector does not come off the circuit board or  should not come off now the circuit board is very   delicate it's got a whole bunch of surface  mount little tiny components the slightest   little bend and I think you're going to damage  this board there are two alignment dowels right   here that keep the board centered over all of  the little terminal pins that these vibration   dampening electrical connectors fit down on  there's all these tiny little delicate   it just scares me to even look at them there's  they're so small and so delicate but you are   just going to lift straight up like that on the  circuit board and then we need to set this down   on this anti-static mat to keep from damaging it  with electrostatic discharge don't take the new   one out of its anti-static bag until you're ready  to put it back on here now if you look right here   below the motor-generator control computer  circuit board that we just removed we've got   some extremely small pins sticking up all over the  place that interface with the back of the circuit   board here they just stick up through those  holes there and they get pinched and held back   down or held together continuity when you press  or lock those vibration-damping connectors back   in place so we've got some electrical connectors  or terminals right here this is for the DC to DC   converter and I put filter capacitor monitor but  I was wrong I was looking at the wiring diagram   and I realized that is just a voltage monitor for  the high voltage monitor going into the DC to   DC converter we have three-phase output to the  mg one and mg2 voltage monitoring circuits right   here we have a smoothing capacitor monitoring  circuit and all of these little tiny terminals   here and let me tip it sideways so you can see it  better in the video here look at how tiny and of   course gold gold-plated and those should not be  touched with your fingers they need to not ever   be bent they've got to be kept straight those are  the control wires and voltage sense wires for all   seven actually there's fourteen IGBT's that are  used in this inverter converter we have six per   electric motors so MG1 has six MG2 has six and  then there are two that are used in the step-up   of the voltage and the step-down of the voltage  with the reactor or the buck-boost converter for   boosting the voltage above the 207.2 volt battery voltage that we have clear   up to on this fourth-generation 600 volts so we  can add almost another 400 volts through a boost   converter okay we disassembled the top of the  inverter converter as far as we are supposed to   but I like to take things apart farther than I'm  supposed to whenever I can and so we are actually   going to separate the upper and lower halves  here in a few minutes and show you what's inside   there also but technically there's nothing else  serviceable in the upper half and in some of the   lower half but clear underneath on the bottom is  the DC to DC converter and that is a serviceable   component so let's turn this around so  that you can see the cooling pipes here on the   end as a matter of fact I'll just lay it on its  end now I'll stick it straight up so we can get   a better view with our overhead camera here so  we've got coolant from I'm sorry coolant going   to the reservoir off of this coolant fitting  and coolant from the automatic transmission   cooler which is external on this model rather  than internal on the lower fitting for us to separate the upper and lower halves or to  even change the entire inverter converter   assembly we need to disconnect this transfer  pipe right here wrench here so this right here okay so we'll undo this top bolt and these two  bottom bolts that hold it in place I'm going to   set this motor generator control computer on the  other side here and get it out of the way and then   we will lift off this plastic transfer tube right  here now if this is full of coolant then at this   point we need to tip it they suggest putting a  couple of blocks of wood underneath it and tip   it up like this and allow the coolant to drain  out and continue to drain and continue to drain   and until there's nothing else left in there tip  a tip it straight up if you need just be careful   not to damage those the dc-to-dc converter  output are 14 and a half volt output and the   two coolant pipes there also with this top cover  removed be real careful not to touch any needles   little pins there now let me show you what will  happen if you undo the upper plastic plugs here   the upper coolant fittings so let me undo these  four fittings I'm gonna keep all these coolant   fittings and their bolts together in a ziploc  bag here all right then we can pull up or out   on the coolant fitting from the or the one that  leaves the inverter goes to the coolant reservoir and then the other one that receives the fluid  from the bottom of the inverter converter the DC   to DC converter it comes here and it goes in here  I want you to notice that these have these stick   down inside and connect to coolant pipes that are  down internal to this inverter converter assembly   so what I'm trying to say is if you before  draining the inverter converter took these out and   then you try to turn them over if you look closely  there you can see that those pipes do not extend   beyond the housing of the inverter converter and  coolant will run down inside of the electronics   that are in here and could damage things could  become a conductive path it's just a huge mess you   you don't want to do that and it tells you in  this service information to avoid that okay   now let's turn this whole thing upside down all  these little delicate pins on the upper portion   of the inverter, converter are recessed below the  housing so they're fine just like that so let's   take off the DC to DC converter cover here next  looks like I've just got eight bolts to keep those   bolts separate this cover is also pretty much  glued on with that form in place gasket sealer   so you've got to pry up very carefully and use  razor blade flat edge to get that to break loose set that off to the side now if you look inside  here you can see the DC to DC converter assembly   so we've got this whole DC to DC converter  assembly we've got these two bolts right here   that are the high voltage connection from the  battery when the battery plugs in the battery   cables the two orange big heavy cables from the  battery plug in they provide power directly to   this DC to DC converter assembly and for  those of you that don't remember or don't   know the DC to DC converter just takes the higher  voltage whatever that may be 200 to 600 volts and   steps it down to 14 and a half or so volts  to charge your 12-volt battery and the rest   of the vehicle runs on 12 volts it's only the  transmission the inverter converter and the air   conditioning system that run on high-voltage  on most cars some of them have a parish to   parish steering system that's high-voltage as  well okay now the DC-DC converter is just a   bolted in housing right here so we have one  electrical connector right here and then we   have one two three four five six seven bolts  eight bolts that hold it down so I'm going to   just undo those eight bolts and the output to  our 12-volt system needs to be unbolted as well I believe that's the last bolt so keep all those  together for the dc-to-dc converter and now we   can just lift out the DC to DC converter so I'm  going to just lift that straight up here it is   right here this is all one piece it is serviceable  you can buy this from any Toyota dealer this is   liquid cooled that's a heatsink on the bottom  there and sensitive electronics so we'll keep   it here on our mat if we look inside the the  inverter converter housing here there's a big   seal ring this black sealing ring here and you  can see where coolant comes in goes around and   goes back out in this lower housing here so when  you change the DC to DC converter you're going   to need to change this gasket that goes with it  all right those are the three pieces that are   serviceable in this inverter converter assembly  we've got the DC to DC converter that's one we've   got the motor-generator control computer that's  number two and that everything else you see right   here this entire housing is number three and of  course you can get the entire unit as   well what we have left over here and I'm going to  disassemble the rest of this is we have another   capacitor right here we have typically have  three capacitors in a hybrid system we have the   smoothing capacitor to smooth out the regenerative  braking or generator three-phase full rectified   inverter voltage bumps and then we have a couple  of filter capacitors as well so let's see what's   inside of this because it's really neat to  see what's inside but once again it's extremely   fragile extremely delicate little pieces we have  some bolts that we're not supposed to take out   I'm taking out next all right there's all four  of those and then we have the bolts around the   outside of the housing looks like we've got  three here two three on the other side and one on   the ends so seven seven bolts total to separate  the two case halves now if you ever go into one   of these just for explorations sake when you  separate these two case halves you must do two   things at once one you've got to break that seal  of the form in place gasket sealer and there's   a couple of price on here once you break that  you've got to lift straight up you can't tilt it   any direction at all because we've got all these  little tiny pins here that go to the vibration   dampening electrical connectors and we don't want  to bend those pins so now I'm going to just lift   straight up there we go and you can see there's  the top of our inverter converter assembly if I   carefully turn that over you can actually see  the IGBTs right over here all of these rows of   solid-state electronics there are the fourteen  IGBTs we'll take a look at those here a little   more detail here in just a moment but let's look  at this bottom housing we've got the reactor   the suppressors or the reactor the inductor and  suppressor that is used to up the 207.2   volts to as high as 600 volts it's just a great  big coil of wire it cycled on and off on the   previous Prius it was a thousand times a second I  don't know what this one is as that cycles on and   off it charges the smoothing capacitor the great  big capacitor that's that's in this upper case   here we have the module that drives it over here  and electrical connectors that go down to the DC   to DC converter a little harness we unplugged and  and so on so let me set the lower half of the   inverter converter assembly out of the way here  and let's look at the upper half because it has   some very interesting components inside of it okay  we have our high voltage wires from the battery   come in right here and they connect of course  to the cable that goes to the air conditioning   compressor and over here to the IGBTs and these  1 2 3 4 5 6 7 rows of IGBTs right here there's 2   IGBTs per row and we have the high voltage DC  power on the top of this plate I have the leads   negative side of the DC power underneath that  plate they as they turn on and off come over   here on the let's see this would be the passenger  side of the inverter converter and connect to the   output terminals to the mg 1 and the mg 2 electric  motors here on this other side we've got the great   big smoothing capacitor but then if you look  down inside right here we've got the resistor   that discharges that big smoothing capacitor so  when you disconnect the high voltage battery   and the service information tells you to wait  for so many minutes it's that resistor that's   discharging it over time and however much time  it takes I'm sure that the time in the service   manual is more than sufficient to get it  discharged even at the highest voltage it   may have may have been but you need to verify  that with a multimeter before going in okay even more interesting is let's look at the coolant passages here we've got the two  coolant pipes coming in and then if you look   right here you can see the two coolant pipes  and if we look on the top side here all of those   little silver brackets in between the individual  black IGBT modules our coolant passages so the   coolant comes in it goes in between every one  of those IGBTs, so we have seven IGBTs looks like   there are nine now there are eight coolant  passages so there's a coolant passage one on   each side of those IGBTs but two of them share  the coolant passages on the inside you can see   heat sink compound thermal transfer grease the  white stuff in there it's got a great big what   looks like a leaf spring in here that is holding  tension on that pack of IGBTs and everything is   welded together you can't disassemble it any  more than I've got a disassembled here because   it's all welded together so I thought that was  interesting to see what's going on inside here   as I said before this inverter converter is  from a 2017 Prius eco the one with the 207   to volt battery you can get Prius with the  nickel-metal-hydride battery I'm sure it   would have an inverter converter very similar  to this but it would have probably different   part numbers for the motor-generator computer  or control computer and possibly some other   things because of how nickel-metal-hydride  batteries are charged versus lithium-ion   batteries we've seen that there is that DC to  DC converter that's fully serviceable and the   motor-generator control computer in the top  half that is fully serviceable except to need   these pliers to remove the vibration dampening  connectors don't try to use a pic or a screwdriver   because you'll just damage them unless you have  better luck than I do now all I have to do is   put it back together and put it back in the  car and make it work thank you for watching

Channel: WeberAuto

Views: 106,539

Keywords: NATEF, WSU, STEM, Inverter, CCAR, Prius Eco, NACAT, ASE, CAT, Guy in wheelchair, IGBT, Smoothing Capacitor, Professor, Prius, Weber State Automotive, Fuull-wave rectifier, Weber State University, Converter, Prius Prime, John D. Kelly, Aisin, 09905-00040

Id: qcW08Mh-eIc

Length: 39min 40sec (2380 seconds)

Published: Thu Oct 19 2017