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Tesla M3LR + Ohme charger: cannot charge

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Not sure if you've resolved this yet, however after much backwards and forwards with Ohme, they have come back with the following.

"Tesla has potentially changed the control line voltage thresholds to a tighter specification than the international standard.

We have already developed new hardware that we believe will resolve this issue with new Tesla model's and have had success with one other customer that had the same issue with a 2020 Tesla."

haha i'm wondering if i'm the one customer :)

Ohme shipped me a new charge point which arrived over the weekend. One of the Octopus installers came by Monday morning and swapped out the charge point - just the unit, none of the other wiring. Took him under an hour, and it worked immediately.

So yes - my issue is resolved, and it clearly was an issue with the charge point. So it was either defective or the new one has some updated firmware (although they should have been able to push that out via a firmware update remotely, no?).

Hardware 'looks' identical, but who knows - maybe the innards are different?
 
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haha i'm wondering if i'm the one customer :)

Ohme shipped me a new charger which arrived over the weekend. One of the Octopus installers came by Monday morning and swapped out the charger - just the charging unit, none of the other wiring. Took him under an hour, and it worked immediately.

So yes - my issue is resolved, and it clearly was an issue with the charger. So it was either defective or the new one has some updated firmware (although they should have been able to push that out via a firmware update remotely, no?).

Hardware 'looks' identical, but who knows - maybe the innards are different?

The issue doesn't seem to have been with the charger, it seems to have been with the charge point, from that description. The charger (actually chargers, as there are effectively three of them in the Model 3) are built in to the car, and they are what takes the 230 VAC nominal mains supply provided at the Type 2 connector, controls the current taken and provides the higher voltage DC charging power to the car battery pack.

My experience was that the issue is solely related to the acceptable tolerance on the CP signal, and normal production variation is likely to change this by maybe 2% or 3% at least. The standard allows for 5% tolerance, but Tesla seems to need this tolerance to be closer to about 3% from what I can see. This means that probably the majority of charge points might work fine, but that the odd one coming off the production line, whilst in tolerance according to the standard, might be just enough out to now work to Tesla's tighter requirement.
 
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The issue doesn't seem to have been with the charger, it seems to have been with the charge point, from that description. The charger (actually chargers, as there are effectively three of them in the Model 3) are built in to the car, and they are what takes the 230 VAC nominal mains supply provided at the Type 2 connector, controls the current taken and provides the higher voltage DC charging power to the car battery pack.

My experience was that the issue is solely related to the acceptable tolerance on the CP signal, and normal production variation is likely to change this by maybe 2% or 3% at least. The standard allows for 5% tolerance, but Tesla seems to need this tolerance to be closer to about 3% from what I can see. This means that probably the majority of charge points might work fine, but that the odd one coming off the production line, whilst in tolerance according to the standard, might be just enough out to now work to Tesla's tighter requirement.

Thanks for pointing out the lingo - I've updated my original post! Your theory makes sense - wonder if they can lower the tolerances via a remote update for other devices?
 
Thanks for pointing out the lingo - I've updated my original post! Your theory makes sense - wonder if they can lower the tolerances via a remote update for other devices?

They were able to fix the non-compliance that caused the car to ignore state changes on the Control Pilot whilst it was asleep via a software update, and as I suspect that control pilot voltage sensing in the charger will be done in the same way that it's done in the charge point, using an analogue to digital converter to sample the CP signal, then it seems possible that they might be able to change the tolerance via a software update. It depends on whether they have hard coded that into the charger or not.

The measurement of the CP voltage when loaded by the car charger is hard coded into my charge points, as, I suspect it is in the Ohme charge points, if a board change was needed to fix it. I can plug a laptop into the programming port on my charge points and just update the code if I needed to change the tolerance when reading the loaded CP voltages (the car charger controls those).

Unfortunately that wasn't a fix for the tolerance problem with my charge point, though, as that stemmed from the inability of the CP drive circuit to deliver a +/- 12 V signal when powered with a +/- 12 V supply. I ended up swapping the power supply for a +/-15 V one, then regulating the supply back down to about +12.6 V, -12.6 V, in order to be able to end up within the Tesla tolerance range. Lots of charge points get away with using a +/- 12 V supply to drive the CP circuit, so there's a chance that others might end up being slightly out of tolerance, too, it may not be just an Ohme thing.
 
Seems to be a recognised issue as Ohme have sent an email out stating Tesla have changed something their end and they are working on a fix.

Anyone else having the issue or have a work around? I'm trying all sorts of combinations of doing things to try and make the charger work but no luck.

Only got the car yesterday and it worked the first time I plugged it in but not since (i should never have unplugged it!).

What charging schedule do people have active when getting it to work?

I've got a daily one that it tries to use straight away then I try to force maximum charging (dumb charging mode) and the unit clicks a bit and i get the AC error in the car.

Granny charger plugged in for now :-( :-(
 
Hi. Having exactly the same problem as described in this post. Tesla 3 delivered few days ago. No problem with DC charging or AC charging with 3 pin plug. However can’t charge with Ohme charge point. Getting same error code and tried ‘max charge’ setting. Came home with 29 miles charge and slowly now charging on 3 pin plug. Waiting for Ohme to reply back after weekend. This thread been very useful to understand potential problem. Thanks.
 
Yeah that's the first thing I disabled - all the smart stuff to see if it'd kick out a charge!

Just tested on supercharger network with no issues, so car is OK!

Perhaps not, I still believe you need to find an AC charger to test the cars on board charging capability. The supercharger will bypass the cars onboard charger and supply DC current directly to the battery. So an AC charging issue may not be seen if connected to a supercharger.
 
It would make sense for all the smart charge points that have been using the Tesla API as a work-around for the bug that used to stop timed charging from working to stop using it now. In addition to making things simpler, it would also reduce the unnecessary usage of Tesla's servers and improve reliability, as it would remove the need for connectivity completely. Once the charge point has been set to charge at particular times, it could carry on doing that even without an internet connection.

I believe the problem that some have been having with the Ohme units may be similar to the problem I had with my charge point initially, that the Tesla charger seems to set a tighter tolerance on the allowable control pilot voltage swing than that in IEC61851.
 
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Now Tesla have fixed the charging software, OHME could do with a software re-write to add in an option that cuts out the Tesla API and just charges when the price is below Xp....or does it already do that?

You can just select a Tesla in the car settings without giving it your login details and it doesn't use the API. You have to manually set what %SoC you want to add and it will still pick the cheapest 30 minute slots to charge.
 
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Hi. Having exactly the same problem as described in this post. Tesla 3 delivered few days ago. No problem with DC charging or AC charging with 3 pin plug. However can’t charge with Ohme charge point. Getting same error code and tried ‘max charge’ setting. Came home with 29 miles charge and slowly now charging on 3 pin plug. Waiting for Ohme to reply back after weekend. This thread been very useful to understand potential problem. Thanks.

Just as an update from me.....ohme have told me that Tesla have changed the tolerances on the charging and as a result they have had to sort new hardware - they have offered to come and swap my unit out for free.

Also though -i restarted my unit (fuse on and off) and since then its been charging as a dumb charger (max charging) and working fine. I dont want to tempt fate and try a smart charge....and will still accept this unit to be swapped out as they offered....but that's where I'm up to and at least I can charge for now....
 
Picked up my model 3 today and have exactly the same problem as described here. Ohme unit clicks but does not charge, even under Max charge conditions. Tesla app shows not charging

Quick update to this; I emailed Ohme about the issue and 30 minute later I got a phone call and a reply by email from Ohme. Thye do know of the issue and latest units have an extra resistor to address this issue. They are sending out a new unit and have contacted the installers to replace. My unit was installed about 3 weeks ago, so must have been the last batch of old units.

Whilst not ideal initially, the customer service to address the problem seems very good
 
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Quick update to this; I emailed Ohme about the issue and 30 minute later I got a phone call and a reply by email from Ohme. Thye do know of the issue and latest units have an extra resistor to address this issue. They are sending out a new unit and have contacted the installers to replace. My unit was installed about 3 weeks ago, so must have been the last batch of old units.

Whilst not ideal initially, the customer service to address the problem seems very good

Same for me. They are replacing the unit to one that works with the new Teslas. Cant fault their customers service considering this sounds like something that isn't actually their fault.
 
Just as an update from me.....ohme have told me that Tesla have changed the tolerances on the charging and as a result they have had to sort new hardware - they have offered to come and swap my unit out for free.

Also though -i restarted my unit (fuse on and off) and since then its been charging as a dumb charger (max charging) and working fine. I dont want to tempt fate and try a smart charge....and will still accept this unit to be swapped out as they offered....but that's where I'm up to and at least I can charge for now....

Ohme sent replacement within 24hrs. However my previous installer won’t be able to swap device for another 2 weeks. From your
Just as an update from me.....ohme have told me that Tesla have changed the tolerances on the charging and as a result they have had to sort new hardware - they have offered to come and swap my unit out for free.

Also though -i restarted my unit (fuse on and off) and since then its been charging as a dumb charger (max charging) and working fine. I dont want to tempt fate and try a smart charge....and will still accept this unit to be swapped out as they offered....but that's where I'm up to and at least I can charge for now....

Ohme sent replacement within 24 hrs but my previous installer won’t be able to swap device for another 2 weeks. I’ll try your suggestion of turning fuse on/off. Even if works as dumb charger it will be better than the 3 pin charging I’m having to do.
 
Ohme sent replacement within 24hrs. However my previous installer won’t be able to swap device for another 2 weeks. From your


Ohme sent replacement within 24 hrs but my previous installer won’t be able to swap device for another 2 weeks. I’ll try your suggestion of turning fuse on/off. Even if works as dumb charger it will be better than the 3 pin charging I’m having to do.

Yeh I've had charger too now - installers are next week for me. It charges as a dumb charger but will randomly click off every 10 minutes (then back on again) so the poor tesla is getting a stop start charge :-(. Luckily I dont need to go far in next week so I'll try just living off this charge until they swap the unit out
 
Interesting having this issue with my Gen 2 Tesla wall charger on our new MY.

Wall charger has been and still does work no issue on the M3.

I opened my door to put something in the car and a whole bunch of red errors popped up on the screen and then went away before I could read. I checked the cars message log and this is what I seen.

-CP_a010 Charging equipment communication error Try again or try different equipment

-CP_a006 Unable to charge service is required

-CP_a044 Unable to charge service is required

-BMS_a063 Unable to charge service is required

-BMS_a063 Unable to charge service is required

-CP_a006 Unable to charge service is required

-CP_a044 Unable to charge service is required

-CP_ a046 Charging equipment communication lost check power source and charging equipment

Car has just over 100 miles on it, connected to a Tesla gen 2 wall charger that we have used for our M3 the past 2 years with never an issue. The car recently finished charging, it was at 91% (was set for 90%). As it does when you sit with a charger connected it was drawing from the wall charger no issue like normal. I unplugged the car and took it out seemed ok ran the battery down to 89% came home and plugged in the charger it charged no issue to 90%. So as of now it drives and seems to charge no issue. But concerned as will be taking a long trip and don’t want to get stuck out of town. Not that it should matter but this is only the 3rd time we have charged the car. What concerns me the most is the "service is required".

Since I have a ranger visit for a few minor issues from pickup this Tuesday I just added to the message part about these errors. I asked if they could check the car remote to see if there is something that needs attention or was this just a freak thing. It is the weekend, so I don’t expect a quick reply.

I Google searched the errors and came up with no matches so wanted to post to see if anyone else has seen or had anything like this.

Today I got a new error in addition to the above tesla "cp_a058" that is how I found this thread.
 
It would make sense for all the smart charge points that have been using the Tesla API as a work-around for the bug that used to stop timed charging from working to stop using it now. In addition to making things simpler, it would also reduce the unnecessary usage of Tesla's servers and improve reliability, as it would remove the need for connectivity completely. Once the charge point has been set to charge at particular times, it could carry on doing that even without an internet connection.

I believe the problem that some have been having with the Ohme units may be similar to the problem I had with my charge point initially, that the Tesla charger seems to set a tighter tolerance on the allowable control pilot voltage swing than that in IEC61851.
Hi Glan, this is Tom from China.
I have a tiny company assemble AC charge point selling in China, 2 years ago I read your reply in this thread about control pilot voltage, and solved my charge point problem on Tesla. Thank you very much!
In fact now I encoutered another problem. When customer used our AC charge point to charge Model 3 or Y, it usually stopped with warning: CP_a044 Unable to chrge service is required. My customer tried to use Tesla Gen 3 WC 2 times and it worked fine.
What is interesting is not all of Tesla cars reported such error, I guess about twentieth(1/20) of cars would report such error.
I know you have rich experience on hardware, software and Tesla cars. Could you give me some advice on this problem?
Thank you very much!