Tesla M3LR + Ohme charger: cannot charge

[chamsters]

Hi all,

Had my ohme installed a couple of days ago - no issues there. Status all OK, reporting fine. No earth rod - it has an earthing device in line.

Today I got my beautiful new M3LR. Plugged it in and nope. A few loud clicks where the Tesla screen shows charging - not charging - charging - not charging, and then gives an error cp_a058 unable to charge on AC, try DC or supercharger.

I have Octopus looking into it as they did the install but they're saying contact Ohme as it's their device. Ohme are also looking into it but saying contact Octopus as they installed the device.

Before I continue this runaround trying to get my home charger to work, any chance anyone here has any similar experiences?

Thanks!

 

[MrBadger]

Have you tried a different AC charge point? Probably worth knowing if its a car or charge point problem.

Where were the loud clicks coming from? Car, earthing device, charge point, fuse box etc If fuse box and earth device, have you checked if any cutouts had blown?

 

[NorfolkMustard]

Try a different AC charger, to make sure the car is OK. Try PlugShare - Find Electric Vehicle Charging Locations Near You to find one (green pins on the map)

 

[chamsters]

Have you tried a different AC charge point? Probably worth knowing if its a car or charge point problem.

Where were the loud clicks coming from? Car, earthing device, charge point, fuse box etc If fuse box and earth device, have you checked if any cutouts had blown?

I'll try another ac point tonight.

Loud clicks are from the ohme device itself - no issues from the matt-e or fuse box etc.

 

[HenryT]

I'll try another ac point tonight.

Loud clicks are from the ohme device itself - no issues from the matt-e or fuse box etc.

I had problems with the Ohme app getting in the way and stopping the charge as soon as it started. I had been trying to use the charger without the app as I didn't need the smart features as we are on a flat rate tariff at the moment, but it seemed that without the app enabled it wouldn't run. With app enabled you can then override any other settings and just tell it to get on with it which is what I routinely do now.

It may be nothing to do with your problems, but worth considering if all else fails.

 

[chamsters]

I had problems with the Ohme app getting in the way and stopping the charge as soon as it started. I had been trying to use the charger without the app as I didn't need the smart features as we are on a flat rate tariff at the moment, but it seemed that without the app enabled it wouldn't run. With app enabled you can then override any other settings and just tell it to get on with it which is what I routinely do now.

It may be nothing to do with your problems, but worth considering if all else fails.

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!

 

[Tony Hoyle]

The people responsible to fix it are the people you bought it from, who in this case I presume would be Octopus.

 

[HenryT]

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!

I'm assuming you got as far as changing the target on the app to 'max charging' at which point the screen turns from blue to red - this is what I have to do each time?

(See here page 10 - https://www.eviuk.co.uk/wp-content/uploads/2020/05/OHME_Quick_Start_Guide_Type2.pdf )

 

[exlatccatsa]

Drop an email to Beth Beth Marsh <Beth.Marsh AT ohme-ev.com> She's always been very helpful in sorting out my charging problems. (stop start every 30 mins)
At the moment, in the summer I'm solar charging so I have to use the max charging switch. In the winter I'll be Agile charging at night and so will use the app as its designed to be used i.e. don't charge above 5p.

 

[MrBadger]

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

Not necessarily. Supercharger is DC, your home charging is AC so the car does the AC/DC conversion that in a supercharger is done by the supercharger.

Unfortunately your error message also implies an AC only issue : cp_a058 unable to charge on AC, try DC or supercharger.

You really need to do an AC charge to be sure its not the car.

 

[Glan gluaisne]

Perhaps try the UMC that came with the car? Should prove whether or not there is an AC charger problem (as the AC charger is built-in to the car, and not used for DC charging).

I'm afraid I can't help with the Ohme specific stuff, as I very much prefer dumb charge points that just do EXACTLY as I want, i.e. switch on and off, when I want them to, using either the front panel switch or an internal time switch for off-peak charging. Sometimes there is a lot to be said for having the power outlet that supplies power to the car (which is all a charge point is) as dumb and simple as any other power outlet in the house.

 

[chamsters]

I'm assuming you got as far as changing the target on the app to 'max charging' at which point the screen turns from blue to red - this is what I have to do each time?

(See here page 10 - https://www.eviuk.co.uk/wp-content/uploads/2020/05/OHME_Quick_Start_Guide_Type2.pdf )

Yep that's exactly what I did.... It would try to start charging before clicking off...

 

[chamsters]

Not necessarily. Supercharger is DC, your home charging is AC so the car does the AC/DC conversion that in a supercharger is done by the supercharger.

Unfortunately your error message also implies an AC only issue : cp_a058 unable to charge on AC, try DC or supercharger.

You really need to do an AC charge to be sure its not the car.

Got a successful AC charge in today with a charger in a business park, so car seems OK!

 

[Harry L]

Did you get anywhere with this at all?

I am having the exact same issue with my Ohme Wall Charger, plug it in and it just clicks. Spent and hour on the phone with the installer going through various troubleshooting to no avail. Works perfectly on a friends Pod Point!

 

[chamsters]

Did you get anywhere with this at all?

I am having the exact same issue with my Ohme Wall Charger, plug it in and it just clicks. Spent and hour on the phone with the installer going through various troubleshooting to no avail. Works perfectly on a friends Pod Point!

Happy to hear someone else has the issue!

Just had the installer (octopus) over who have verified all electricals are fine. They're talking to Ohme now to get a replacement device as that's the only item left that can't be fully verified. Car works, electricity flows, but car and ohme aren't speaking. Car speaks with other chargers, so that's not the issue.

 

[Glan gluaisne]

Happy to hear someone else has the issue!

Just had the installer (octopus) over who have verified all electricals are fine. They're talking to Ohme now to get a replacement device as that's the only item left that can't be fully verified. Car works, electricity flows, but car and ohme aren't speaking. Car speaks with other chargers, so that's not the issue.

Not sure I understand this, as the test box that gets plugged into the charge point lead as part of the mandatory functional testing during installation simulates the car interface. As far as the charge point is concerned (any AC charge point, not specifically the Ohme one) the test box is a car, electrically there is no difference, and mechanically there isn't much difference, except most test boxes don't bother to include the solenoid/motor operated connector latch (this has no effect on functionality).

If the car charger works with other charge points, then it's not a charger fault, but by the same token, if the installer has done the job properly and completed the functional testing of the charge point using the simulator test box then that should have shown up the problem. You cannot get power at the charge point connector terminals without using a test box to simulate the charger interface, so I suspect that the installer just may not have bothered to do the required functional check. Might be that the installer doesn't have the test box, but if that's the case they shouldn't be doing the job, especially as they will have signed the Part P installation certificate to say they've completed all the testing required, and that includes a functional test.

This video shows what a typical vehicle simulator test box looks like, at around the 30 minute mark, and it's clear from this that the installation cannot be tested without one:

I have a simulator test box, looks a bit different as it's home made, but I wasn't able to do the mandatory testing on my own charge point installations without it, hence the reason for knocking it up. Been very handy since, as it makes the diagnosis of any problems a very simple and quick process, as well as being required whenever I do a routine EICR on anywhere that has a charge point fitted (including our own house). I'm always happy to do a quick (free) test for anyone within reasonable distance of Salisbury, as it's not uncommon to find that some installers aren't that great at doing the required functional testing of charge points, perhaps because they don't have the right kit.

 

[chamsters]

Not sure I understand this, as the test box that gets plugged into the charge point lead as part of the mandatory functional testing during installation simulates the car interface. As far as the charge point is concerned (any AC charge point, not specifically the Ohme one) the test box is a car, electrically there is no difference, and mechanically there isn't much difference, except most test boxes don't bother to include the solenoid/motor operated connector latch (this has no effect on functionality).

If the car charger works with other charge points, then it's not a charger fault, but by the same token, if the installer has done the job properly and completed the functional testing of the charge point using the simulator test box then that should have shown up the problem. You cannot get power at the charge point connector terminals without using a test box to simulate the charger interface, so I suspect that the installer just may not have bothered to do the required functional check. Might be that the installer doesn't have the test box, but if that's the case they shouldn't be doing the job, especially as they will have signed the Part P installation certificate to say they've completed all the testing required, and that includes a functional test.

This video shows what a typical vehicle simulator test box looks like, at around the 30 minute mark, and it's clear from this that the installation cannot be tested without one:

I have a simulator test box, looks a bit different as it's home made, but I wasn't able to do the mandatory testing on my own charge point installations without it, hence the reason for knocking it up. Been very handy since, as it makes the diagnosis of any problems a very simple and quick process, as well as being required whenever I do a routine EICR on anywhere that has a charge point fitted (including our own house). I'm always happy to do a quick (free) test for anyone within reasonable distance of Salisbury, as it's not uncommon to find that some installers aren't that great at doing the required functional testing of charge points, perhaps because they don't have the right kit.

View attachment 586613

Spot on. He didn't do this testing on initial install (or if he did I didn't see) - but he did bring the test box this morning. His box reported no errors - he was able to initiate 'charge' and cycle through all the modes.

So even if it's not an electrical issue or a functional issue, something is clearly not right, and whatever that something is can't be captured by the functional tests he conducted nor the voltage checks he carried out. Whatever it is, i'm impacted by the problem, but it's not my problem to resolve nor Tesla's.

 

[Harry L]

Spot on. He didn't do this testing on initial install (or if he did I didn't see) - but he did bring the test box this morning. His box reported no errors - he was able to initiate 'charge' and cycle through all the modes.

So even if it's not an electrical issue or a functional issue, something is clearly not right, and whatever that something is can't be captured by the functional tests he conducted nor the voltage checks he carried out. Whatever it is, i'm impacted by the problem, but it's not my problem to resolve nor Tesla's.

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."

 

[GRiLLA]

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

Interesting. When my Model 3 was new last August I had a similar issue with the EO Mini Pro that I had installed. It tested fine but the car wouldn't charge, my installed got EO on the case. The Model 3 was new in the UK and EO hadn't been able to test with it before, so their CTO came round to my house with lots of things to try. He concluded that Tesla was being far more strict on the voltages required for the control signal than the standard. Their devices had a range based on some component, so he swapped parts of my charger to be within this tighter tolerance and I've been good ever since. I think I heard they then changed their manufacturing and components to make sure other customers didn't have the same issue.

Perhaps Ohme have changed something and now fallen fowl of the same issue.

 

[Glan gluaisne]

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."

This seems to be true. I had a little bit of unreliability with my (home made) charge point and the Model 3. I pinned it down to the tolerance on the Control Pilot signal that the Tesla charger will accept. The standard (Table A.1 in IEC61851) is that the nominal open circuit swing for the CP signal is from +12 V to -12 V, with an allowable tolerance of +/- 0.6 V. My charge point CP signal was within that tolerance, at about +11.6V to -11.5 V, but sometimes the charger in the car flagged up a charging equipment error.

After a lot of fiddling around, comparing the voltage on the CP of the UMC under all operating states, I modified my charge points to increase the control pilot voltage swing slightly, and now it's about +12.3 V to - 12.2 V, and it works flawlessly.

It isn't uncommon for manufacturers to ignore the technical specification, and in fact Tesla ignored another part of IEC61851 for a couple of years, the bit that requires the car charger to respond if the CP changes from State A to States B or C when the car's plugged in (Tesla only fixed that a couple of months ago). Many EVs will work without the negative going part of the CP signal, even, and are happy with the signal just going from ~+12 V to ~0V.