Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Roadster 3.0

This site may earn commission on affiliate links.
Good chance that when they replaced the PEM they didn't properly re-attach the blower housing that keeps it cool. It attaches under the driver's side of the PEM. You may be able to see the edge of it between the PEM and ESS. I had that happen to mine, and I was able to wiggle and wedge it into place well enough from above to let me drive the car to the SC for them to attach it properly. That was one disaster of an "annual maintenance" visit.

Be careful, though. The daily top-off charging can overtemp the PEM, too.

That's probably not my issue, as the PEM cools properly when not being pushed.

Essentially, I live at an elevation of 2250'. So, driving up the mountain to get home has always put a load on my car, even though the speeds are under 40 mph. That said, I never ever got to the point where the PEM was overheated that "Power Limit" came on, even when temps were over 100º F. Now, it happens with temps in the mid 80's.

I hate to say it, but I suspect that the PEM itself isn't up to snuff. Whether that's a design defect or manufacturing I obviously can't say. But, my car goes into service again on Monday. My guess is they'll come back with "works fine for us" and give me my car back. And now that it's many weeks later, the temps may not be hot enough to make this happen, even if they take some of the mountain roads.

I'm really regretting doing the upgrade right now. My car was just fine. I just wanted more range. Sigh.
 
  • Helpful
Reactions: drewski
Don't let them get away with leaving you with a bum PEM. I regularly would climb over 1,000 up in the 100 degree summer at freeway speeds with no trouble. Yes, it got hot, but never power limited. The only times I got power limited was climbing the Sierra's (only momentarily) , and when they botched putting the air housing back on. Oh, also when the PEM fan connector fried its contacts. Maybe grab the logs and look for any 1144 or 1146 alerts. Then see my thread in the Technical section regarding (not) needing a new PEM fan.
 
  • Like
Reactions: dhrivnak
Another datapoint: My 2.5 PEM runs warm (3 bars) within 5 minutes of leaving home and when driving slow in traffic. But it then cools down to 1 bar when 'giving it the beans' . Then the motor temp gradually goes up. Clean and functioning cooling.

I'm guessing this is a combination of a slightly mis-calibrated temperature sensor and transistors doing less work, less 'chopping', as more power just flows to the motor.
 
...I hate to say it, but I suspect that the PEM itself isn't up to snuff. Whether that's a design defect or manufacturing I obviously can't say...
I'm having a hard time believing the PEM design does not have enough cooling capacity. I'm leaning strongly on the theory that something is wrong with your specific PEM or your cooling system. I can't see any reason why the new pack would create heat at a higher rate in the PEM than the previous pack.

I just picked up my car today after getting the 3.0 battery and immediately drove 155 miles at 70mph. Ambient temp was 78 F. The PEM never went over 34 C for the whole trip, and it only got that high when I was climbing a mountain. The downhill portions the PEM averaged 31C.
 
Aerodynamics
The original Roadster had a drag coefficient (Cd) of 0.36. Using modern computational methods we expect to make a 15% improvement, dropping the total Cd down to 0.31 with a retrofit aero kit.

Rolling Resistance
The original Roadster tires have a rolling resistance coefficient (Crr) of 11.0 kg/ton. New tires that we will use on the Roadster 3.0 have a Crr of roughly 8.9 kg/ton, about a 20% improvement. We are also making improvements in the wheel bearings and residual brake drag that further reduce overall rolling resistance of the car.

Question for those who have undergone 3.0 upgrades (2021 and earlier): did it only include battery, PEM, and firmware modifications, or did it also include the retrofit aero kit and rolling resistance improvements described in the initial 3.0 announcement?

Were either of the latter ever mentioned again, described in more detail, or demonstrated publicly outside of the Christmas 2014 letter?
 
As I suspected, Tesla was unable to find anything wrong. That didn't stop them from calling me up today to tell me that "it's fixed" and come on down to pick it up. They've had the car over 3 weeks now.

When I asked them what was done, well, they checked the fan and it was fine and they checked the ducting and it was fine and they looked at the heat sinks and they looked fine and they went to clean the PEM but it wasn't dirty, and they drove it and it didn't overheat and cools down fine.

Of course, by now it's Oct and the outside temps are 60º instead of 80º-90º+ and they're not driving it uphill.

And, they know it overheats because the technician told me he was able to pull at least one of the records of overheating based on my date/time information. There are two instances I recorded, and it's overheated at least 3 times in the days immediately after the 3.0 upgrade.

At this point the only good thing is that I haven't paid the remaining $25K for the upgrade.
 
As I suspected, Tesla was unable to find anything wrong. That didn't stop them from calling me up today to tell me that "it's fixed" and come on down to pick it up. They've had the car over 3 weeks now.

When I asked them what was done, well, they checked the fan and it was fine and they checked the ducting and it was fine and they looked at the heat sinks and they looked fine and they went to clean the PEM but it wasn't dirty, and they drove it and it didn't overheat and cools down fine.

Of course, by now it's Oct and the outside temps are 60º instead of 80º-90º+ and they're not driving it uphill.

And, they know it overheats because the technician told me he was able to pull at least one of the records of overheating based on my date/time information. There are two instances I recorded, and it's overheated at least 3 times in the days immediately after the 3.0 upgrade.

At this point the only good thing is that I haven't paid the remaining $25K for the upgrade.
I bet Carl Medlock can figure it out.
 
As I suspected, Tesla was unable to find anything wrong. That didn't stop them from calling me up today to tell me that "it's fixed" and come on down to pick it up. They've had the car over 3 weeks now.

When I asked them what was done, well, they checked the fan and it was fine and they checked the ducting and it was fine and they looked at the heat sinks and they looked fine and they went to clean the PEM but it wasn't dirty, and they drove it and it didn't overheat and cools down fine.

Of course, by now it's Oct and the outside temps are 60º instead of 80º-90º+ and they're not driving it uphill.

And, they know it overheats because the technician told me he was able to pull at least one of the records of overheating based on my date/time information. There are two instances I recorded, and it's overheated at least 3 times in the days immediately after the 3.0 upgrade.

At this point the only good thing is that I haven't paid the remaining $25K for the upgrade.

Take @slcasner's advice and push for your PEM with the new bits.

If they didn't do anything, it isn't "fixed"
 
8F929EE2-5F8D-48B9-B170-55967113ABE9.jpeg
Signature 100 #54 is now back on the road with a 3.0 battery. Limited use so far but everything seems to be operating as expected, except the TPMS module isn’t reading tire pressures and is throwing a fault. It took 2.5 months to figure out how to get all of the right parts to the right place to be installed so I didn’t want to leave it there any longer to fix the TPMS. The car has been a brick for the past six or seven years so it’s great to see it back alive.
 
@Zak Congrats! Which SC did the install? Can you go into more detail on the “getting the right parts to the right place” delays?
Thank you. The Rocklin, California service center did the install. I originally booked it for Fremont but switched to Rocklin, which seems to have caused an issue with getting all of the correct parts to the new location (even though I made the change weeks before the appointment). The new battery was installed but the PEM was all wrong so it took a long time to get a proper PEM (for a 1.5 powertrain). Once the PEM was installed they realized the new battery was not charging and was in fact depleted top a point that it would not charge. They had a second battery on hand but that one also turned out to be depleted. It took a while to diagnose and attempt to repair because their emergency charger for low batteries had been lent to another facility and they had to drive to get it. Another battery was ordered, which took time. The service center was communicative and helpful but it didn't seem they were getting the support they needed from HQ. I also needed new tires and it turns out the tires Tesla has in the warehouse are expired, so another few days to source front tires. It took about 2.5 months in total for the upgrade. Many more details not worth going into that made it challenging. So far so good though and I am happy with the result.
 
Thank you. The Rocklin, California service center did the install. I originally booked it for Fremont but switched to Rocklin, which seems to have caused an issue with getting all of the correct parts to the new location (even though I made the change weeks before the appointment). The new battery was installed but the PEM was all wrong so it took a long time to get a proper PEM (for a 1.5 powertrain). Once the PEM was installed they realized the new battery was not charging and was in fact depleted top a point that it would not charge. They had a second battery on hand but that one also turned out to be depleted. It took a while to diagnose and attempt to repair because their emergency charger for low batteries had been lent to another facility and they had to drive to get it. Another battery was ordered, which took time. The service center was communicative and helpful but it didn't seem they were getting the support they needed from HQ. I also needed new tires and it turns out the tires Tesla has in the warehouse are expired, so another few days to source front tires. It took about 2.5 months in total for the upgrade. Many more details not worth going into that made it challenging. So far so good though and I am happy with the result.
Thanks for sharing Zak. I am curios if the range on your car immediately showed the higher R80 values? I also have the new 3.0 and it did not show initially. Thanks again for sharing your experience.