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1.5, 2.0 and PEM temps

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One thing interesting about having the 2.0 loaner is that I can drive my usual driving habits and observe / compare the PEM, Motor, and Battery temps..... What I'm noticing is that the 2.0 PEM is staying allot cooler than my 1.5 PEM. I peaked the 2.0 at 100F / 38C. It then recovered fast after that.... My 1.5 easily would rise higher than that when pushing it... granted it wasn't a blistering day but I was pushing it and expected the 2.0 PEM to go higher. So I'm impressed with that.

Curious... did the 2.0's come with the dual PEM fan/Blower? I know that the 1.5 used inductive charging which built heat up on the motor and could rise to the PEM... but was there any other changes other than the obvious design that would make the PEM run cooler?

I'll try to peak to see if the 2.0 has the dual blower...

Battery and motor appeared to stay the same... although I saw the battery rise and drop rather quickly.... I do hear that the water pump appears to be running faster/ higher pitched when sitting so possibly its circulating the water through the pack faster to do a quicker cool-down from faster heat discipation.
 
So I got my Roadster back today and Menlo Park was able to confirm that the PEM does indeed recover faster than the 1.5 PEM from higher temps. I pushed the loaner really hard across Woodside road this morning which is all but straight, lots of hard twisty turns and I did the trip early in the morning where there wasn't really any traffic. Again the car performed well, except for the brakes as I mentioned. I wouldn't trust those damn Brembo's to stop me for anything... there's nothing but fade and failure there. So I really couldn't push as hard into the turns as my 1.5 since I have the CarboTechs that bite with confidence. However I pushed the car hard coming out of each turn floating and pushing the front wheels out of the turn... you can feel them just lighten up and not respond until you let off the accelerator which is all controllable. Anyways... to get to the point the PEM would bump up a block but rapidly recover as soon as I got off the pedal. So that was super nice. In comparison I watched my PEM temps on my 1.5... just going over Highway 17 back to Santa Cruz which isn't as bad as Woodside road... and the PEM temps definitely hung steady at the last blue block and stayed there for a while (it hasn't been all that hot here but the temps have been consistent across the time of the 2.0/1.5 switch). I'm also noticing my battery temps staying higher too on the 1.5... so I'm thinking from that noisy coolant pump in the 2.0 that its circulating the coolant faster as I stated before.

A couple things I learned:
The 2.x PEM fan is always running whereas the 1.5 PEM is on a thermostat and kicks on when needed. I took notice charging the 2.0... its fan was always running whereas my 1.5 would shutdown. So running all the time charging was kinda annoying... my 1.5 is way quieter bigtime over the 2.0 in all aspects of charging and sitting. However when driving there's something with the 2.x design that is evident that it really works. I think the thermostat is still a good design, no need to keep running it when you don't, but I'd like to have the cooler temps that's for sure which may be linked with the updated fan design. I think the 1.5 can't upgrade from what I heard such as the PEM fans but it can have the dual blower mod.

The 2.x has a dual blower that also helps force more air to the PEM compared to the 1.5 that only has one. These blowers blow air to the motor's heat sink as well as to the PEM, there are two ducts that are routed... one to the PEM and one to the motor that are shared with this blower.

There are two fans on the PEM itself on the 2.x, but I think I got this right that there are also two on the 1.5. But somehow the 2.x's are better. I have to look at some breakdowns of the PEM to confirm and understand this.

Happy I got my Roadster back. Miss the 2.0's seats, the part that holds your body in place. I also can feel and miss the extra padding on the butt portion but didn't like the height it bumped me up by. Would love to have my 1.5 seats with the 2.0 side grippies, the 1.5 lumbar pump, and a padding but but also to drop the seat down so you don't get any height difference. Going through the turns in the 1.5 I definitely could feel my torso shift side to side which felt a little sloppy. It also definitely gives more of a sports car feel with those seats compared to the 1.5's.

I also noticed that the rear end handling was somewhat tighter and better on the 2.0. The difference there was the rear swaybar, the 2.0 had an adjustable thicker swaybar due to the dual blower fan it was built with. However there's two adjustable swaybars I saw on two different Roadsters today. One that came out further towards the rear for the dual blower (on my 2.0 non-sport loaner) and one that did not which was weird since it was a 2.5 (non-sport) Roadster. Both were adjustable. I have to email Tesla to really understand that one, we both (MP Tesla and I) were puzzled by it.

Also happy to have my 1.5 shift select back. I really don't like the buttons or the brightness of those things at night. Backed into my driveway without looking down at the gear selection which is nice and way smoother of a transition.

Would be sweet to build a Roadster that was the best of the best, a combination of a 1.5 with the added advancements of the 2.x's and definitely make it a Sport Please :)
 
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FYI the brightness of those lights is tied to the dimmer control for the console. You can turn them down.

True but they are dimmed out of sync... How'd they make production that way? Anyone drive the 2.x at night before releasing it? I'd put an adjustable voltage regulator and a resistor in there for those shifter lights if I had a 2.x so they dim at an equal level. Its way too intense as they are now... I like having my instrument gauges bright at night but not my buttons. Who the hell wants them that bright anyways by default? LEDs are intense, that's why their replacing HIDs for headlights. I had to set the dimmer to the lowest setting and still the selection buttons were bright. They should have been shut down at that point. The true issue is that the buttons are way brighter than the instrument cluster and don't dim at the same rate. They should give off the same illumination at full intensity and don't dim synchronously.

I just picked up a Jeep Rubicon to go wheeling in Arizona and Utah in the summer... put an aftermarket LED license plate light on it was more like a Flood / Reverse light since they were so intense. I'm dropping the voltage across the 12 (overkill) white LEDs for system as I stated above to make it legal but not overwhelming. I really don't need to shine a 10' x 10' area just to illuminate my license plate.
 
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Curious... did the 2.0's come with the dual PEM fan/Blower? I know that the 1.5 used inductive charging which built heat up on the motor and could rise to the PEM... but was there any other changes other than the obvious design that would make the PEM run cooler?

My 2.0 #506 did not come with the dual fan assembly/blower for the PEM. I had to pay extra for it when my original failed. Since I had an early 2.0, not sure if they added it to 2.0s later. 2.25?

My Roadster is noticeably louder now, but i've noticed the PEM stays a lot cooler which is worth it.
 
No, the mod was invented after the 2.5's were already shipping. It was retrofitted to all cars in Northern areas because their fans were routinely failing - apparently due to road salt ingress. Some people had multiple replacements.
 
True but they are dimmed out of sync... How'd they make production that way? Anyone drive the 2.x at night before releasing it? I'd put an adjustable voltage regulator and a resistor in there for those shifter lights if I had a 2.x so they dim at an equal level. Its way too intense as they are now... I like having my instrument gauges bright at night but not my buttons. Who the hell wants them that bright anyways by default? LEDs are intense, that's why their replacing HIDs for headlights. I had to set the dimmer to the lowest setting and still the selection buttons were bright. They should have been shut down at that point. The true issue is that the buttons are way brighter than the instrument cluster and don't dim at the same rate. They should give off the same illumination at full intensity and don't dim synchronously.

I think there must be variance amongst cars. Mine work pretty well and at the dimmest setting the push buttons lights are almost off.

The camera can't really show this, but I made an attempt anyway:

 
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