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Timer charging restricted to 16A?

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I think that's not true of @HenryT 's 2015 Model S - it certainly isn't of my 2014 model. I think the change came in with the facelift and the switch to the Model X charger (max 24A 3-phase), but I am not 100% sure and there might have been an intermediate variation.

Certainly early EU Model S had in effect 3 16A, single phase charging modules, or 6 of them if you ordered the 'dual charger' extra-cost option. The base model could charge from 32A single phase using the UMC, because the UMC blue commando adaptor bridged the three phase pins together; these cars could only charge at 16A from a standard 32A single-phase chargepoint. That was just about tolerable in mainland EU where domestic 3-phase is more common (and domestic high-current single phase rare), but in the UK with the OLEV scheme meaning that most people would have a free 32A chargepoint at home it was a significant problem. Just before launch in the UK, Tesla and Chargemaster flirted briefly with a plan involving Chargemaster units with the phases bridged, but it was rapidly realised this was a bad idea (such chargepoints blow up Renault Zoes for example), so the modified chargepoints were withdrawn and Tesla fitted all UK-delivered Model S with dual chargers whether you had ordered them or not. Somewhat later, a software kludge was implemented that stopped you charging faster than 16A on three-phase unless you had paid for the second charger.

So on this generation of Model S (unlike later Model S or Model 3 etc) there is no switching hardware to fail and result in a 16A limit. It is of course possible for the second charger to fail or for the software limiting kludge to have gone wrong. I wonder if Henry's car has the 2nd charger paid for.

Thanks for your time and trouble in explaining that Arg, though I'm afraid some of it I'm struggling to follow.

I don't have a clue if I have the second charger, to be honest. I can't say I've seen it mentioned anywhere but not sure I'd have noticed if I did. I bought the car used in Jan last year so don't have the original papers (if there were any).

Charged the car today on a public charger and as expected the car drew 32A - didn't have the time to set it up as a timed charge so just plugged in and got 32A, just as I do at home.
 
I have been having a different problem since installing 2020.48.12.1 - though possibly related.

The car seems to charge normally for non-timed charging.


It does seem like there is something amiss with the combination of older cars, waking to charge from a sleeping state and 2020.48.12.1 software. So far I have had no reaction from Tesla in respect of my service booking for this but expect I will hear from them before the booked date of 2/2
 
I don't have a clue if I have the second charger, to be honest. I can't say I've seen it mentioned anywhere but not sure I'd have noticed if I did.

The only way to tell externally is by attempting to charge on 3-phase - if dual chargers it will go to 32A, single charger to 16A. The AC hose on triple-head rapid chargers is the easiest place to find such a chargepoint.

In theory, you used to be able to find it by the option codes through the Tesla API, but that has reputedly become inaccurate in recent times. Unfortunately, logging in to your account on Tesla.com doesn't tell you (at least for my car).
 
The only way to tell externally is by attempting to charge on 3-phase - if dual chargers it will go to 32A, single charger to 16A. The AC hose on triple-head rapid chargers is the easiest place to find such a chargepoint.

In theory, you used to be able to find it by the option codes through the Tesla API, but that has reputedly become inaccurate in recent times. Unfortunately, logging in to your account on Tesla.com doesn't tell you (at least for my car).

I don't see anything about chargers/dual chargers on the spec for mine on Tesla.com either. Just confirmation of free supercharging and premium connection and such like.

I do get 32A plugged into my charger at home but we are only on single phase supply. 16A only ever rears its head on a timed charge and like your problem, rights itself if I pull/re insert the plug.
 
Mine failed again last night - having done the plug/replug and got it charging, I manually stopped the charge and left it to wake up again at midnight for the scheduled charge - which again gave the start/stop/start/stop behaviour and no charge. Cable hadn't been touched in between, so highly unlikely to be poor contact on the connector. Does seem like a software problem.

One possible related issue is that each time I've looked at it and got the charge started, the battery has been so cold that it couldn't charge - it was running the battery heater but showing 0 mph charge rate, showing (IIRC) 20/32A as the heater takes less than 7kW (I didn't leave it long enough to warm up and actually start charging). So it's conceivable the problem only occurs when the weather is cold.
 
Good point - I wondered if the cold weather may also be a factor.

I have only had the Octopus tariff for a couple of weeks so I didn't have any reason to use a timed charge before now. My timing experiments so far have all been during very cold nights.
 
Well last night's experiment didn't get me any further...

Went out at 00.15 to let the car wake up and have a blast of 32A charging - all went as expected and charge delivered as it should. Left the cable connected but stopped the charge using the Tesla app. Set the timer on the Wallbox app to start charging from 00.30 - at this point the Tesla app showed 'connected - waiting for charge' or similar, and 0/32.

Clock strikes 00.30 and charging starts - Tesla app shows available/anticipated amps immediately drop from 0/32 to 0/16 then climbs steadily to 16/16 and stops there. Left it 20 mins and car gets a steady 11 mph charge at 16A.

Pulled plug and plugged back in again, amps jumps to 32A and 23 mph and off we go...

Must be software. Waiting on Tesla response so will update as/when I find out any more.
 
Still not clear if my problem is related to Henry's or is a completely different issue.

I also tried a different experiment last night - I couldn't be bothered to wait to midnight to reset the inevitable failed charge, so I tried to kick it off manually (from the app) about 23:30. Even that manual start failed, but going out to plug/unplug and then starting again from the app made it start OK and the charge finished successfully sometime during the night.

So it looks like my issue triggers whenever the car is woken from sleep to charge, but charges OK if it has been awake between the plug going in and the charge starting. Still to be tested - what if the car is woken up for some other purpose and then the charge started?

Like Henry's issue, mine seems almost certainly software.
 
It wouldn't be the first time that there's been a software related charging problem. For around 18 months (first reported around January 2019 by US owners) there was a flaw in the Model 3 charge control software that prevented a charge from starting when the car was asleep. The manual stated that the car should start the charge turn on sequence as soon as the CP changed from State A to State B (in effect), but in reality the car just stopped monitoring the state of the CP line as soon as it went into a deep sleep. Waking the car up, either by unlocking it or using the app, started it charging normally.

This fault was quietly fixed, without any mention in the release notes, by an update rolled out in June last year. I'd reported it to Tesla, and they rang me the day that the update rolled out to ask me to check if the problem was still there or whether it had been fixed, so it was clear that they knew about it, but didn't want to go public that this software bug had been around for so long.

It seems probable that something similar may be afflicting the Model S, perhaps. It wouldn't be the first time that a software update has broken functions that have worked fine until that time.
 
It wouldn't be the first time that there's been a software related charging problem. For around 18 months (first reported around January 2019 by US owners) there was a flaw in the Model 3 charge control software that prevented a charge from starting when the car was asleep. The manual stated that the car should start the charge turn on sequence as soon as the CP changed from State A to State B (in effect), but in reality the car just stopped monitoring the state of the CP line as soon as it went into a deep sleep. Waking the car up, either by unlocking it or using the app, started it charging normally.

This fault was quietly fixed, without any mention in the release notes, by an update rolled out in June last year. I'd reported it to Tesla, and they rang me the day that the update rolled out to ask me to check if the problem was still there or whether it had been fixed, so it was clear that they knew about it, but didn't want to go public that this software bug had been around for so long.

It seems probable that something similar may be afflicting the Model S, perhaps. It wouldn't be the first time that a software update has broken functions that have worked fine until that time.

AS well as the wake up to charge issue we also specifically had a 16amp charging limiting software bug in the model 3 last year that affected a number of cars...
 
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I have a Wallbox and the only way I've managed to get timed charging to work is as follows.

1. The Wallbox is set to charge from 16:30 to 04:30.
2. The car is set to charge from 00:30.
3. I plug the car in at 6 ish each night (this is within Tesla's 6 hour window to allow a charge to start. On plugging in, the car handshakes and charges for 30 seconds, stops, and then waits until 00:30 to charge.
4. At all times the car shows 16/16amps, whilst the Wallbox shows 32 amps, crucially the car chargers at 32 amps.
5. The charge is terminated by the Wallbox at 04:30.

This has always worked for me, but I still don't know why the car insists on showing 16 amps.
 
I have a Wallbox and the only way I've managed to get timed charging to work is as follows.

1. The Wallbox is set to charge from 16:30 to 04:30.
2. The car is set to charge from 00:30.
3. I plug the car in at 6 ish each night (this is within Tesla's 6 hour window to allow a charge to start. On plugging in, the car handshakes and charges for 30 seconds, stops, and then waits until 00:30 to charge.
4. At all times the car shows 16/16amps, whilst the Wallbox shows 32 amps, crucially the car chargers at 32 amps.
5. The charge is terminated by the Wallbox at 04:30.

This has always worked for me, but I still don't know why the car insists on showing 16 amps.
Is this for a model S or 3 ?
It does seem to be that Teslas like to default to 16a, probably because of the 3 phase default charging position they seem to have.
Then once it starts the charge cycle, it realises only then it's on single phase, only then does it (hopefully) goto 32a.
Seems an odd arrangement you have there, but as we might say it's a workaround that works for you.
 
That's weird. I have timers on our charge points, set to activate them at the start of the off-peak period each night. I can plug my Model 3 in any time, and it just starts charging as soon as the charge point turns on, and stops charging either when the set charge level has been reached, or the charge point turns off on the timer, whichever comes first.

This didn't always work, there was a bug in the Model 3 software that prevented this working until June this year, when it was fixed via a software update. I leave the car permanently set to "charge immediately", and all that happens if the charge point timer is off is that it displays a message that it's waiting for the charging equipment, or something similar.
 
I have a Wallbox and the only way I've managed to get timed charging to work is as follows.

1. The Wallbox is set to charge from 16:30 to 04:30.
2. The car is set to charge from 00:30.
3. I plug the car in at 6 ish each night (this is within Tesla's 6 hour window to allow a charge to start. On plugging in, the car handshakes and charges for 30 seconds, stops, and then waits until 00:30 to charge.
4. At all times the car shows 16/16amps, whilst the Wallbox shows 32 amps, crucially the car chargers at 32 amps.
5. The charge is terminated by the Wallbox at 04:30.

This has always worked for me, but I still don't know why the car insists on showing 16 amps.

Thanks for that Bistoptom - sounds bizarre but worth a try, I'll give it a go.

My only reservation is that when my car shows 16/16A and the charger app shows 32A being offered the actual charge added/increased range achieved is consistent with a 16A charge.
 
Still not clear if my problem is related to Henry's or is a completely different issue.

I also tried a different experiment last night - I couldn't be bothered to wait to midnight to reset the inevitable failed charge, so I tried to kick it off manually (from the app) about 23:30. Even that manual start failed, but going out to plug/unplug and then starting again from the app made it start OK and the charge finished successfully sometime during the night.

So it looks like my issue triggers whenever the car is woken from sleep to charge, but charges OK if it has been awake between the plug going in and the charge starting. Still to be tested - what if the car is woken up for some other purpose and then the charge started?

Like Henry's issue, mine seems almost certainly software.

@arg - Looks like you are not alone with the start stop charging problem - 2020.48 lack of sleep and bizarre charging issues
 
@arg - Looks like you are not alone with the start stop charging problem - 2020.48 lack of sleep and bizarre charging issues

Thanks - I'll now post my further results to that thread as it seems identical to my issues, while your problem may or may not be the same one.

My latest info: last night charging worked OK (both manual and timed), but a significant difference is that it was warmer - the battery heater did not run and charging started immediately, compared to the previous behaviour where (once kicked into actually working) it was running the battery heater before being able to start actual charging.
 
My wall charger is a 'Wallbox Pulsar' not a Zappi.

I have tried using the delayed start in the Tesla and using the timing schedule in the app the Wallbox has. Both lead to the same conclusion unfortunately.
Having recently signed up to Octopus Go I have just started using timed charging to take advantage of the lower rate between 00.30 and 04.30. The problem is though, that whenever the timed charging starts, it only ever runs at 16A, not the 32A I would normally get if I just plugged the car into the charger without the timer being set. This has remained the case all the way through the 4 hour period, charging at around 11mph compared to a typical 23mph my car normally reports.

My car (MS 70D 2015) was recently updated to 2020.48.12.1 but I haven't found reports of others with this particular update having a similar problem.

The charger (a Wallbox) happily delivers 32A if I just plug it straight into my car without any timing restriction and also delivers 32A (27mph) on a timed cycle if my wife's ID.3 is connected with the timer set (using the Wallbox app to manage the timing).

I have tried using my car for the timing with 'start charging from...' set but the outcome is the same. While the car is charging at 16A the option to increase the charge rate above 16A is greyed out and just shows 16/16 available. Before the timer kicks in though, and with the cable plugged in it shows 0/32 and 'ready to charge'.

To add insult to injury, the charger app shows 32A being delivered (or rather, made available) but again the car only reports 16A. The voltage is fine at up to 244v and there are no settings in the timer set to deliver reduced power, so I am not sure if there is anything else to check?

Do you think this is something that might be resolved in a further update (as happened previously) or should I be reporting this to Tesla? (I am out of warranty by the way, so no doubt I would be charged to investigate the problem).

Failing that, any other suggestions?

(I have tried a couple of re-boots, following the software update)
Hi Henry,

I've been having exactly the same problem since about January 2021, pretty much the same time as yours kicked off.

I have a Model S 85 and a Wallbox. The Wallbox says it has 32 amp available but the car only takes 16 amps on scheduled charges. During the day it will usually take 32 amps but even manual attempts to charge it during the night (stop 16 amp charge and restart) only result in 16 amp. When it starts a scheduled charge it show 32/32 but as soon as the current starts flowing it reduces to 16/16. The other thing I have noticed is that voltage starts high, about 246-247 then drops very quickly to under 240, sometimes down to 232.
I have contacted Tesla and they said they couldn't see anything wrong. I contacted have Wallbox and they did a software update (after the Wallbox show a red circle and refused to charge either the Tesla or the Zoe). Wallbox say they will have to replace the Wallbox if it shows the red circle of death again. I have also contacted my DNO about the supply, they are looking into it.

If you have resolved your issue I would love to know your solution. If you haven't maybe we should compare notes and then jointly bug Tesla or Wallbox.

Regards
Andy Bury
 
Hi Henry,

I've been having exactly the same problem since about January 2021, pretty much the same time as yours kicked off.

I have a Model S 85 and a Wallbox. The Wallbox says it has 32 amp available but the car only takes 16 amps on scheduled charges. During the day it will usually take 32 amps but even manual attempts to charge it during the night (stop 16 amp charge and restart) only result in 16 amp. When it starts a scheduled charge it show 32/32 but as soon as the current starts flowing it reduces to 16/16. The other thing I have noticed is that voltage starts high, about 246-247 then drops very quickly to under 240, sometimes down to 232.
I have contacted Tesla and they said they couldn't see anything wrong. I contacted have Wallbox and they did a software update (after the Wallbox show a red circle and refused to charge either the Tesla or the Zoe). Wallbox say they will have to replace the Wallbox if it shows the red circle of death again. I have also contacted my DNO about the supply, they are looking into it.

If you have resolved your issue I would love to know your solution. If you haven't maybe we should compare notes and then jointly bug Tesla or Wallbox.

Regards
Andy Bury
Hi Andy,

Interesting to hear I'm not the only one with this problem.

Once or twice since we have had the warmer weather mine has performed properly on a timed charge which has lead me to conclude it was temperature related. (The previous episodes had been during a very cold spell with temp around zero). I even tried it out on a timed start on a public charger while walking the dogs and again it worked ok with 32A reported. Smug with success, I decided it had cured itself and assumed it was a matter of history, or at worst, seasonal. Had another go recently and we are back to 0/32 before the timer kicks in then 16/16 once the charge starts.

I had been resigned to the fact it isn't going to work reliably and have either accepted it will only charge at 16A on a timer or hang around till 00.30 (we are on Octopus Go,) and go outside and plug it in to start the charge manually.

Like you, I didn't get anywhere with Tesla as they told me that everything was fine after a remote check. In a fit of pique, I even went to the local SC (Stockport) to try to replicate the problem on one of their AC chargers. Typically, it worked fine although I couldn't tell quite what the display in the car was telling me as it showed 16/16 (3) - evidently a 3 phase setup. Given that it was charging at around 46 mph I had to assume all was well.

My conclusion is that this is a problem about the way the Wallbox and my car talk to each other, but like you, I struggle to get anyone prepared to pursue this beyond the "it's not us, it's them..." The frustration is that my wife's ID.3 charges perfectly on a timed charge.

Based upon my experience to date, I don't have much faith that Tesla are interested enough to do anything more about this, but Wallbox may be more helpful?

Perfectly happy to make a joint representation to Wallbox if you think that might be worthwhile, perhaps we could refer them to this thread as a starting point?
 
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I have also been having the same problem with my Model S P85 (2014 model) since the start of 2021. It went in to Tesla but the situation was not resolved and they appear to be blaming the wall charger (a Rolec Wallpod), but I have never had a problem with it previously and if I force the charge to start then it charges at 32A with no problem.
I have done various tests on scheduling a charge at different times of the day. Curiously if the scheduled time is the same calendar day and less than 120 mins from when I connect the tether, then it charges at 32A but if the time is over two hours it always, or in the next calendar day, it charges at 16A.