What would be the normal range for the temps of MG1 and MG2? I am still taking data with Priidash, but I do see temps over 50C when going slowly in hilly country, lots of regen braking and electric boost up steep sections. This is during warm, not hot weather. Speeds average in the 15-30 mph range. Cars works great and getting 50+mpg according to the screen. No indication of any trouble. Inverter temps are in the 40C range. MG1 and MG2 go down into the 40C range once I get onto faster road. I am going to look at the radiators and make sure they are very clean, but I wonder if there is too little air flow at the slower speeds.
Make sure you have good turbulence in the Inverter Coolant reservoir reflecting good flow through the pump which is under TSB. And replace Inverter Coolant asap. You will see your temps plummet with fresh Inverter Coolant. The Inverter is the heart & soul of this car. And this coolant also cools the transmission. Its very very easy to replace this coolant yourself. Pat Wong has an excellent write up on it.Search. When you get the coolant out of the car look at it in a glass jar and you'll see what I mean.
As long as it is < 60 °C, it is normal. ORNL did a test on the Gen2 and reported 50°C was not exceeded in a mild urban drive cycle, while 60°C was not exceeded in the most demanding drive cycle that the vehicle could track (Pittsburgh cycle). The stator-thermal protection is set at 174°C, which indicates that Toyota is protecting the winding as if it is a Class H motor winding. Class H allows operation at up to 180°C for an average life of 20,000 hrs. Vincent
