And Where are these Electric Motors (RX450h +)

[Albeelexus]

Recently traded my naturally aspirated 6 cylinder RX350 to naturally aspirated 4 cylinder + Electric motor hybrid and plug in RX450h+.

I do miss the smooth (low key) yet powerful 6 cylinder in the RX350 compared to the (loud) strained 4 cylinder in the  RX450H+. Luckily the 4 cylinder in the RX450h+ is only used as an "on need" basis and therefore tolerable 😊

Compared to the RX350 the RX450h+ has a pleasing  "getup and go" quiet and  punchy acceleration. And  I'm still trying to fully understand the configuration of motors that are in the vehicle .   

I've heard that their are a total of 4 motors  (1x 4 cylinder naturally aspirated + 3 x electric motors ) in the RX450h+.

Can anyone confirm if the  "1x 4 cylinder naturally aspirated + 3 x electric motors " configuration is accurate and where the electric motors are  located ?

 

Appreciated  😊

  

[Stefano-S]

MG1 and MG2 (Motor/Generator 1 & 2) are located inside the CVT transaxle housing and the third motor is in the center of the rear axle area, much like a differential on a more conventional automobile.  This is only connected to the front of the drive train electrically and not mechanically, meaning that there is no front to rear driveshaft.

[Albeelexus]

Tks  Stefano-S.....  !! GREAT  Info !!  .  🙂

From your description .. 1 X MG for each front wheel and 1 X MG used for both rear wheels.... I'm assuming the 4 x Cylinder gas engine is not used for moving the vehicle and used only for recharging the main and 12vlt batteries and support to  AC / Hydraulics..  etc  ?

 

Cheers  🙂

[Stefano-S]

As I mentioned, both are enclosed in the eCVT housing which is attached to the engine (ICE).  MG1, the smaller one of the two acts as a starter motor for the ICE and also as generator to charge the lithium battery pack located in the rear.  As you are most likely aware, there is no external starter motor or alternator, nor any drive belts on these engines.  MG2, the larger one of the two, is the drive motor for the planetary gears for the front wheels, and also acts as a generator to recharge the battery pack during braking and deceleration.  Needless to say, this is a highly sophisticated system.  Toyota wrote the book on Hybrid Synergy Drive and IMO, they are the best in the automotive industry.  They are, however, not perfect.  The 12v auxiliary battery in the rear cargo area is charged by the lithium battery pack.  The charging algorithm by which this is done really needs to be fine tuned, IMO.  There are dead 12v battery issues which are well known throughout the Toyota/Lexus hybrid community.  I have taken to monitoring the state of charge on both of my Lexus PHEV's on a daily basis to insure that the 12v batteries do not drop below 12.4v, a point at which battery sulfation and resulting degradation begins to occur.  At least weekly, I charge my 12v batteries with an external charger to insure a longer battery life and to make certain that I don't get stranded.

[Albeelexus]

Wooooo  "Stefano-S" .. take it slow 🙂.... Took me re-reads to grasp your well written and informative .    Their should be some emoji /Icon to show appreciation for such info and details...  (Much appreciated ) 

On the 12vlt battery issue .. its so " not good " that such a sophisticated (expensive) vehicle built on Toyota reliability would have 12vlt battery problems. 

Within recent days I've found three other  RX450ht's in the neighborhood with similar concerns.

Thanks again for your well informed response ..

Cheers 

[Stefano-S]

10 hours ago, Albeelexus said:

Wooooo  "Stefano-S" .. take it slow 🙂.... Took me re-reads to grasp your well written and informative .    Their should be some emoji /Icon to show appreciation for such info and details...  (Much appreciated ) 

On the 12vlt battery issue .. its so " not good " that such a sophisticated (expensive) vehicle built on Toyota reliability would have 12vlt battery problems. 

Within recent days I've found three other  RX450ht's in the neighborhood with similar concerns.

Thanks again for your well informed response ..

Cheers 

I agree that this is a bit of a disappointment on Toyota's part.  While they are spot-on in the majority of their engineering marvels, the 12v battery charging algorithm for the standard hybrids and PHEV's, leaves much to be desired.  In short....It really kinda sucks to have such a nice car with a crappy charging problem with the 12v auxiliary battery.  I have a plug-in voltage gauge (about $10) in the center console (12v lighter socket) of both cars to monitor the power going to the battery.  When driving, it normally stays at 12.6v, which is enough to run A/C, lights, blower motors, etc but, not enough to charge the battery.  On rare occasion it will randomly go to 14.3 to 14.4v, when driving and also, any time that the car is in PARK with the READY light on, it will reach this battery charging voltage level.   I also carry a  NOCO Boost XL GB50 1500 Amp 12-Volt Lithium Jump Starter in each of my 450h+ cars. It may seem like overkill but, I consider it cheap insurance in the event of a dead battery. I hope that they will eventually sort this out and give us an OTA update for the algorithm.  In any event, I would welcome any kind of an update from the mothership for this issue.   

[Albeelexus]

" In any event, I would welcome any kind of an update from the mothership for this issue. "    (Stefano-S) 

By now you should realize how star struck I am on your Lexus knowledge, info and details. You certainly have my vote to approach the" mother ship" on our behalf towards some resolution to this  battery issue. If you do follow up, kindly share updates.

In interim (like you) I have a NOCO GB40 in my vehicle for Jump-start eventualities. NOCO also have nifty  battery chargers like the "NOCO Genius10" which works very well for battery maintenance.

Thanks again for having taken the time with responses. Looking forward to your info with other enquiries.  😆 

Cheers 

 

[Stefano-S]

17 hours ago, Albeelexus said:

" In any event, I would welcome any kind of an update from the mothership for this issue. "    (Stefano-S) 

By now you should realize how star struck I am on your Lexus knowledge, info and details. You certainly have my vote to approach the" mother ship" on our behalf towards some resolution to this  battery issue. If you do follow up, kindly share updates.

In interim (like you) I have a NOCO GB40 in my vehicle for Jump-start eventualities. NOCO also have nifty  battery chargers like the "NOCO Genius10" which works very well for battery maintenance.

Thanks again for having taken the time with responses. Looking forward to your info with other enquiries.  😆 

Cheers 

 

Thanks much.  I have a NOCO Genius 5 and a Genius 1, as well.  I also have NOCO X-Connect eyelet terminals on my batteries to permit my weekly charging of the 12v's.  Yes, it's a bit of a PITA but, it is what it is until Lexus gives us all an algorithm update to cure this issue.  Thanks again for your kind comments.