Wireless charging in M3 makes phone very hot

[Tony Hoyle]

I find the car's wireless charger rubbish. It's very slow and heats up, and often doesn't charge at all.. no such problems with my home wireless charger - doesn't even get warm and charges as fast as the USB cable. I suspect it's just an old design.. early wireless used to be like that (I can remember trying it and giving up as it was so fiddly to align), but it improved massively.

Since they changed the design to add the wireless chargers you can no longer route a cable into that area either.. so you end up with a mess of wires.

 

[Adopado]

I find the car's wireless charger rubbish. It's very slow and heats up, and often doesn't charge at all.. no such problems with my home wireless charger - doesn't even get warm and charges as fast as the USB cable. I suspect it's just an old design.. early wireless used to be like that (I can remember trying it and giving up as it was so fiddly to align), but it improved massively.

Since they changed the design to add the wireless chargers you can no longer route a cable into that area either.. so you end up with a mess of wires.

I think these things work best if the charging area lines up nicely with the phone. It's often hard to tell if the phone is sitting in the optimum position ... which is understandable given the different sizes of phone. My cheapo version works like a charm but I put it down to good luck with the alignment rather than it being a superior design (hardly likely, and bought in 2020 so probably older than the ones installed by Tesla).

 

[LostVector]

I had a similar problem with extremely slow charging and heat today in my 2023 Model Y in combination with an iPhone 13 Pro + official Leather Magsafe case.

After experimenting a bit more tonight, I think I may have figured out the parameters. At least with my particular phone and case, it charges fine if I do my best to center the phone horizontally on the respective pad and, most importantly, lay the phone as close to the bottom while still being flush with the flat area of the charger.

The fiddly part is that it's naturally tempting to seat the bottom of the phone down as far as possible. catching it on the lip of the charging area. Well, the bottom of the charger is both curved and has a lip. So seating it as far down at possible will lift the back of the phone away from the charger and make charging ineffective. That's my going theory, anyway. Would be great if others could confirm.

Unfortunately, I'm not sure if just driving is enough to jostle the phone out of place and into this undesirable state. Ideally someone could make a little shim or adapter to place and hold the iPhone in position better.

 

[Durzel]

It would probably help in the future if Tesla altered the wireless charging pad to have a recess for camera bumps. Their OG wireless charger had this recess, which meant current generation phones actually sat flat on the pad. The current one, being flat, means that the back of the phone is lifted off by a few millimetres.

I don't think camera bumps are going away any time soon, so it seems logical that Tesla alter their design even if it doesn't look as aesthetically pleasing (although the top part of the charge is obscured by the screen in use anyway really).

 

[hgmichna]

I have a Pixel 6 and happen to have an app installed that shows the current charging power (AccuBattery). So I could quickly do an experiment.

I placed my phone, as usual, into the left charging pad and pushed it to the right, against the center lip that separates the two pads. The phone charges with about 3 to 3.3 W.

Then I pushed it about 1 cm = 0.4 inch to the left, and it charged with 8 to 8.5 W.

So for me the solution is clear. I will get a 1 cm wide strip and use it to keep the phone on the left side of the pad. The ultimate test will happen on the next longer-distance drive.

 

[Loco_Nomad]

Same here, my iphone 12 pro max gets super hot. Charges fine though, 20% fills up during my commute home/work etc. More than enough, wish it didn't get hot that much. Still better than in my legacy X, it doesn't have any charging nor enough USB ports to charge. We can always use USB-C to charge though

 

[LostVector]

I gave up on this ... wireless charging the phone in the car is a bit of a lost cause IMO. It can get hot even with a perfectly aligned charger aka MagSafe. Combine that with any sort of active tethering or usage and it's too much for the phone. I went with a magsafe compatible charger that has a peltier cooler built into it and that's taken care of the charging slowness completely, but at the expense of being less clean as it needs a wire to run to the charger.

 

[Tes1aFanBoy]

Same experience here but my phone never used to get hot when charging. Makes me wonder what’s changed?

 

[StrykerFoxx]

I have the iphone 12 mini (which I hate and gonna replace soon) and I have the same problem. Half the time the phone doesn't charge cause it's not aligned properly, and even when it does charge it gets really hot. I would like to just turn off the wireless charging, since 99% of the time I don't need my phone charged, it's just a convenient place to put my phone. Is there no way to turn it off?

 

[MrT3]

Is there no way to turn it off?

No, not unless you dismantle and disconnect it. Someone suggested to Musk the option to turn it off which he agreed would be a good idea but that hasn’t happened yet.

 

[Adopado]

No, not unless you dismantle and disconnect it. Someone suggested to Musk the option to turn it off which he agreed would be a good idea but that hasn’t happened yet.

This seems an advantage for the earlier Model 3 where you could add your own wireless charger (for £32 in my case) with each side being active or inactive or both active. Having the USB ports directly below is also very convenient for a hub, SSD and for charger connectivity.

 

[hgmichna]

Rather than switching the wireless charging off, wouldn't it be better to fix it such that it works well?

 

[MrT3]

Rather than switching the wireless charging off, wouldn't it be better to fix it such that it works well?

That’s almost impossible to do with phones being all different shapes and sizes and their coils in different places. It works, but just not optimally or efficiently.

I also don’t always want my phone to be charged but want somewhere to store it whilst driving.

 

[jsmay311]

The mat in the car only has a single coil for each phone charger and - as noted in this thread - you get heat when the coils don't line up properly.

This shows the Model Y has 2 coils. I would assume the Model 3 would have the same, but idk for sure.

Even still, these 2 coils are spaced out enough to explain some amount of added inefficiency and heat generation if the phone’s coil is lined up in between the 2 charging coils.

 

[stopcrazypp]

This shows the Model Y has 2 coils. I would assume the Model 3 would have the same, but idk for sure.

View attachment 978352

Even still, these 2 coils are spaced out enough to explain some amount of added inefficiency and heat generation if the phone’s coil is lined up in between the 2 charging coils.

The Tesla pad is extremely sensitive to alignment (my 2021 Model 3 one is also, not sure if it's the same however as Model Y's). It would help a lot of both the pad and the phones have the optimal center point marked, but unfortunately they don't do that. Instead pads that are more "universal" do it by using many coils.

That testing tool in the video is very interesting. The closest thing I have on my phone is the Accubattery app, which shows my charge current and voltage.

 

[Durzel]

it would probably help considerably if the wireless pad had a recess for the camera bump, which is never going away.

The original wireless charger addon for the 3 had this. I know it doesn’t look as good aesthetically, but at least the phone wouldn’t be like raised 2mm off the coil, even more with a case.

 

[jsmay311]

I also don’t always want my phone to be charged but want somewhere to store it whilst driving.

One suggestion I’ve seen for using the dock without having it charging the phone is simply to place the phone in the dock with its screen side facing down.

 

[SpareHeadOne]

This shows the Model Y has 2 coils. I would assume the Model 3 would have the same, but idk for sure.

View attachment 978352

Even still, these 2 coils are spaced out enough to explain some amount of added inefficiency and heat generation if the phone’s coil is lined up in between the 2 charging coils.

To the best of my knowledge the original Tesla pad had a single coil because that was a complaint aimed at it by people who had previously used a third party mat designed to fit into the original console.

It's entirely possible that this is a newer version or those original reports were incorrect, but thatt's largely irrelevant because the positioning of the coils is not suitable for the early iPhones with wireless charging as they had the coil mounted about ⅔ of the way up the back of the phone rather than centrally like they newer ones do.

It'll all become even more irrelevant in future since Apple submitted MagSafe to the Wireless Power Consortium (WPC) - of which they are a member - and it has been adopted as part of the Qi2 standard, so we are starting to seen Android phones appear that are compatible with existing MagSafe chargers as well as new Qi2 chargers. All of that means we will almost certainly see a MagSafe/Qi2 charger in Teslas of the future so hopefully everyone can be happy.

 

[TechnoWatch]

That’s almost impossible to do with phones being all different shapes and sizes and their coils in different places. It works, but just not optimally or efficiently.

I also don’t always want my phone to be charged but want somewhere to store it whilst driving.

It would be pretty simple to have an adjustable bottom stop on the pad so you could alter the positioning of the phone relative to the coil.

Even better, also having a switch to turn off the charging entirely so it can just act as a phone holder.

 

[MrT3]

Even better, also having a switch to turn off the charging entirely so it can just act as a phone holder.

As has already been stated further up, there was a suggestion that Tesla might add a software switch to disable it but it hasn’t happened yet.