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UMC button sometimes doesn't unlock cable

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Recently (last few weeks?) I've had the problem that the button on the UMC handle doesn't properly unlock my charge cable. The light cycles a few different colors, briefly (split-second) flashes white for unlocked, but then goes back to the color it started with and re-locks. In this situation I've taken to unlocking the cable by long-hold on the trunk button of the fob, which always works (so far).

I haven't fully characterized the circumstances when this does and doesn't happen, but it seems to correlate with my having been away from the car for some time. That is, if I pull in to my garage and then immediately try to replicate the problem, I can't. This is true even if I walk away from the car so that it locks, or if I lock it manually. Yes, I've made sure that the fob is present and the car unlocked (the handles are presented) when I try pulling out the UMC handle.

I don't think the onset of the issue correlates with a software update, so I'm starting to wonder if I have a defect in my UMC, although the fact that it sometimes works makes me skeptical. I haven't had the opportunity to test with other UMCs or a Supercharger cable.

I'd appreciate any suggestions or pointers to threads that may already cover this (I've tried searching to no avail).
 
I want to hear an update too. Mine's been doing the same thing for a few weeks now too, but I've been hesitant to go to the SvC since I can't replicate it always.

My car is definitely unlocked when I try to do it.
 
Recently (last few weeks?) I've had the problem that the button on the UMC handle doesn't properly unlock my charge cable. The light cycles a few different colors, briefly (split-second) flashes white for unlocked, but then goes back to the color it started with and re-locks. In this situation I've taken to unlocking the cable by long-hold on the trunk button of the fob, which always works (so far).

I haven't fully characterized the circumstances when this does and doesn't happen, but it seems to correlate with my having been away from the car for some time. That is, if I pull in to my garage and then immediately try to replicate the problem, I can't. This is true even if I walk away from the car so that it locks, or if I lock it manually. Yes, I've made sure that the fob is present and the car unlocked (the handles are presented) when I try pulling out the UMC handle.

I don't think the onset of the issue correlates with a software update, so I'm starting to wonder if I have a defect in my UMC, although the fact that it sometimes works makes me skeptical. I haven't had the opportunity to test with other UMCs or a Supercharger cable.

I'd appreciate any suggestions or pointers to threads that may already cover this (I've tried searching to no avail).
I've had this happen a couple of times in the last two months. It hasn't happened since my last update 2.34.215 yet so it might be a firmware update.
 
this happens to me almost everytime. i unluck hte doors with the key fob. i even open the trunk.
i can hear it dissengage, but then it locks it again. eventually, i'm able to pull itout. but its definitely not on the first attempt.
 
Try first unlocking your car door by presenting the FOB. Then pushing the button on the UMC or HPWC.
Thanks -- that's what I'm doing already ("Yes, I've made sure that the fob is present and the car unlocked (the handles are presented) when I try pulling out the UMC handle.") BTW the same applies if I unlock by double-tapping the fob.
Best bet is to HOLD the button until it goes white, then pull the cord. Don't just press then release.
I'll give that a try, thanks. It used to work fine with just a tap, so I'm still going to call this a defect, but if long-hold works that would be an acceptable workaround.
 
Pressing the button does 2 things: It makes the proximity line in the charge port go high, and it transmits a radio signal on 315Mhz do the car.

The proximity signal if restored is that same mode that tells the charger it's OK to start charging, so pressing it only briefly will stop/release but when you let off the button, the proximity line will go back low and it will re-latch.
 
I had something like this happen as well. I did a service center appointment, and they said that a firmware update had made it mandatory to hold the UMC button down, especially when actively charging. They said they first saw this in the X's and, having been given no info about the change, had also assumed it was an error and had to escalate, themselves, to figure out what was happening.
 
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Pressing the button does 2 things: It makes the proximity line in the charge port go high, and it transmits a radio signal on 315Mhz do the car.

The proximity signal if restored is that same mode that tells the charger it's OK to start charging, so pressing it only briefly will stop/release but when you let off the button, the proximity line will go back low and it will re-latch.
I will second this, and mention that a J1772 handle behaves the same way. Pressing the unlock button will unlatch it briefly, but to keep it unlocked, you generally need to hold the button down as you pull it out.
 
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Could there possibly be a problem with the actual button on your UMC?
Wow, cant believe I ran into this thread. I have been having these same type of issues since I have owned my S75D. In fact, I just called the tech service line this morning and asked them if the "over the air data info" (whatever it's called) could possibly point out the problem. I have been wondering whether my problem was with the button on the adaptor handle or the receiver, which is supposedly mounted to the left and up from the charging port. if anybody gets an answer from tesla, I hope they post it in this thread.
I suggested that if enough people have this problem they should provide a tab on the touch screen which would force the receptacle circle to stay "light blue" until the driver pulls out the adaptor. This way we could at least drive the car after it has been charged. This is the problem I had this morning..........I thought I was going to be stuck at home because I couldn't remove the umc.
 
I will second this, and mention that a J1772 handle behaves the same way. Pressing the unlock button will unlatch it briefly, but to keep it unlocked, you generally need to hold the button down as you pull it out.
That notwithstanding, it didn't behave that way for me until quite recently. Furthermore, tap-to-unlock still works sometimes, so the behavior is not consistent from a user experience point of view. If that's how it behaves now, OK, I will adapt.
Pressing the button does 2 things: It makes the proximity line in the charge port go high, and it transmits a radio signal on 315Mhz do the car.

The proximity signal if restored is that same mode that tells the charger it's OK to start charging, so pressing it only briefly will stop/release but when you let off the button, the proximity line will go back low and it will re-latch.
Thanks for the explanation. That suggests that the inconsistent behavior I'm seeing might relate to whether the car is trying to draw current from the UMC, or not. If it is, your description suggests that if the car is actively consuming juice when I tap the button, what's happening is as soon as I release the button the car starts sipping again and the port re-latches, but if the car is quiescent then the port should stay unlatched. If this is right, I should be able to trigger the bug (or "bug") by using the app to engage the climate control. I'll give it a try. It also suggests that maybe what changed is the firmware didn't used to be so aggressive about grabbing shore power again as soon as it became available.
Could there possibly be a problem with the actual button on your UMC?
It could be ("I'm starting to wonder if I have a defect in my UMC, although the fact that it sometimes works makes me skeptical") although the info from @Ingineer suggests otherwise.
 
Wow, cant believe I ran into this thread. I have been having these same type of issues since I have owned my S75D. In fact, I just called the tech service line this morning and asked them if the "over the air data info" (whatever it's called) could possibly point out the problem. I have been wondering whether my problem was with the button on the adaptor handle or the receiver, which is supposedly mounted to the left and up from the charging port. if anybody gets an answer from tesla, I hope they post it in this thread.
I suggested that if enough people have this problem they should provide a tab on the touch screen which would force the receptacle circle to stay "light blue" until the driver pulls out the adaptor. This way we could at least drive the car after it has been charged. This is the problem I had this morning..........I thought I was going to be stuck at home because I couldn't remove the umc.
Keep in mind that you can always unlatch it by doing a long-hold on the trunk button of the fob. Or at least this has always worked for me. I'm also going to try continuous-hold on the UMC button as several have suggested.
 
Keep in mind that you can always unlatch it by doing a long-hold on the trunk button of the fob. Or at least this has always worked for me. I'm also going to try continuous-hold on the UMC button as several have suggested.
Thanks, Nikola. I did read that response about continuously holding the trunk button on the fob. Just haven't tried it yet. That would certainly be a easy solution to that part of this problem
 
If it is, your description suggests that if the car is actively consuming juice when I tap the button, what's happening is as soon as I release the button the car starts sipping again and the port re-latches, but if the car is quiescent then the port should stay unlatched. If this is right, I should be able to trigger the bug (or "bug") by using the app to engage the climate control. I'll give it a try.
Just tried it; happened as predicted. That is, tapping the button worked with the car unlocked and the climate control off (charge port light blue). With the climate control engaged (light throbbing green) tapping the button didn't work (light cycles white->blue->back to green) but continuous hold did.

Thanks again. Continuous-hold will do as a workaround although I kinda hope they revert the behavior, I liked it better the old way.

Come to think of it, I bet this change is why the motion I used to use to remove the J1772 adapter stopped working. I used to slightly unlatch the J1772 cable (interrupted charging), then relatched it to the adapter and used the J1772 handle to pull the adapter out. Sounds clumsy when written out but in practice it worked for me almost as smoothly as pulling the UMC handle out. It stopped working and I didn't think much of it, but I bet the reason is the car has gotten more aggressive about resuming charging. Anyway, now I just pull the J1772 handle off, then grab the adapter and pull that out in a second motion.
 
I have to back my car in to charge at home. When I approach my car from the rear I always have to make sure I'm in close enough proximity to the driver door for the handles to present itself. I learned this early on into ownership as to why I wasn't able to unlock my charging handle. Same goes for holding down the button as opposed to just clicking it briefly.
 
Just tried it; happened as predicted. That is, tapping the button worked with the car unlocked and the climate control off (charge port light blue). With the climate control engaged (light throbbing green) tapping the button didn't work (light cycles white->blue->back to green) but continuous hold did.

Climate control shouldn't control whether or not the car is actively charging, but blue vs. green does indicate standby vs. charging. My 2013 has always taken longer to "release" the cable when I approach the car when it's actively charging versus not. However, it does not take a too long of a press. I hold mine down until I see the light change to white and never have a problem, but that likely is longer than simply "clicking" the button.