Charging Issue

[utsteve98]

So I’m having issues with my car fulling charging. I am using my PMCC that came with the car. Had no issues before. But now I plug in and come back and see it has stopped charging after a few hours and not going to my target of 85%. I even did direct charging and still same issue. There are no errors on the PMCC or car. Just says charge complete. It is hot here in Texas even in my garage so not sure that has an effect. But it’s been hot all summer and haven’t had this issue before. Anyone else dealt with anything similar?

Sponsored

 

[Jhenson29]

Have you tried both ports? I get this sometimes on one port (passenger) when it’s hot. No issues on driver side port.

On passenger side, when it does it, it will start again if I unplug and replug.

 

[daveo4EV]

So I’m having issues with my car fulling charging. I am using my PMCC that came with the car. Had no issues before. But now I plug in and come back and see it has stopped charging after a few hours and not going to my target of 85%. I even did direct charging and still same issue. There are no errors on the PMCC or car. Just says charge complete. It is hot here in Texas even in my garage so not sure that has an effect. But it’s been hot all summer and haven’t had this issue before. Anyone else dealt with anything similar?

https://www.taycanforum.com/forum/t...uide-to-the-porsche-evse-pmc-pmcc-pwcc.13886/

I agree with trying the "other" charging port - but anything involving the PMC+/PMCC is suspect based on my experience - if possible I'd try an alternative EVSE…

 

[DerekS]

The Porsche unit commonly overheats and fails. You can cut the power to 50%, but the better move is to replace it with one that actually works.

 

[EddieD]

So I’m having issues with my car fulling charging. I am using my PMCC that came with the car. Had no issues before. But now I plug in and come back and see it has stopped charging after a few hours and not going to my target of 85%. I even did direct charging and still same issue. There are no errors on the PMCC or car. Just says charge complete. It is hot here in Texas even in my garage so not sure that has an effect. But it’s been hot all summer and haven’t had this issue before. Anyone else dealt with anything similar?

I am having this exact same problem. I live in Scottsdale Arizona where it’s been very warm this summer. Whether I am using the time charging feature or direct charging lately it’s just been charging about 25% of the desired amount and then shutting down. I believe the problem is related to the Porsche mobile charger, connect cable which from prior posts, apparently is poor quality with 10 gauge wire rather than 8 or 6 which results in overheating. I have 4 gauge wire going to the outlet and the outlet is very high-quality so I know this is not the problem. From various posts, it seems that Porsche is blaming, poor quality outlets, and not their cable. What they would like you to do is bring the charger in and have it reprogrammed so it only charges at half the normal rate therefore doubling the charging time. What I’ve had to do is unplug the charger and let things cool down and then start the process again and it’s taking about three episodes of charging to get me up to 85%. Very frustrating. One answer is to just buy a new charger but it’s unfortunate that Porsche is not providing us with a high-quality charging cable.

 

[daveo4EV]

I am having this exact same problem. I live in Scottsdale Arizona where it’s been very warm this summer. Whether I am using the time charging feature or direct charging lately it’s just been charging about 25% of the desired amount and then shutting down. I believe the problem is related to the Porsche mobile charger, connect cable which from prior posts, apparently is poor quality with 10 gauge wire rather than 8 or 6 which results in overheating. I have 4 gauge wire going to the outlet and the outlet is very high-quality so I know this is not the problem. From various posts, it seems that Porsche is blaming, poor quality outlets, and not their cable. What they would like you to do is bring the charger in and have it reprogrammed so it only charges at half the normal rate therefore doubling the charging time. What I’ve had to do is unplug the charger and let things cool down and then start the process again and it’s taking about three episodes of charging to get me up to 85%. Very frustrating. One answer is to just buy a new charger but it’s unfortunate that Porsche is not providing us with a high-quality charging cable.

there is a bit more nuance to this but you have the broad outline mostly intact

• Porsche is not wrong about low quality outlets - cheap NEMA sockets are not designed to provide 9.6 kW for multiple hours on end daily, weekly, monthly with _ANY_ EVSE - only high quality ceramic/commercial/industrial quality NEMA outlets should be used with _ANY_ EVSE including Porsche's and others…see Porche's document for the correct part numbers
  • the $12-$35 leviton NEMA 14-50 outlet from homedepot/lowes is _NOT_ the correct choice to provide power for _ANY_ EVSE
• Porsche's NEMA 14-50/6-50 power supply cables use AWG 10 wire - which for 40 amp continuous loads will get a bit toasty by human standards - but is completly safe given Porsche's choice of 105C temp-rate insulating plastic. There are no reports that I'm aware of where Porsche's power supply cable demonstrates any systemic failure or safety issue
  • Porsche's power suppy cable getting hot sucks, is no good, and 100% un-necessary - but it's not unsafe it just runs hotter than people expect and vs. other competitive/alternative EVSE's
• The witches-brew of a power supply cable that runs "hot by design" and a low quality outlet that is not designed to handle hours of thermal stress is now in hindsight a bad combination, but it's difficult to pin blame down in this case. Porsche is allowed to say "use better components" our stuff is fine, but it would also be possible for Porsche to ship an alternate design that places less thermal stress on related non-Porsche components involved in a residential home charging circuit.
• I suspect, but do not know for a fact - the charging problems in this case honestly has _NOTHING_ to with the power supply cable in this case, but rather the PMC+/PMCC unit itself - my experience with my PMCC's is they are finicky/temperamental beasts and easily give up on a charging session at the first sign of trouble - I would not describe them as robust and resilient. My suspicion is this is simply a less frequent and separate thermal problem, that is unrelated to the powersuppy cable (although it can't be helping) where the PCM+/PMCC unit itself has problems operating at full capacity when there are high ambient termperatures (can you same summer? I knew you could). So the PMCC unit quietly stops the flow of power once it experiences thermal stress so that it does not permanently fail. Porsche would most likely characterize this as a "safety" feature in that the unit is shutting itself down in an orderly an controlled manner to preserve it's operational integrity and avoid failure/melting/burn-out due to thermal stress.
  • attempting to operate Porsche's EVSE in a high ambient temperature environment 90F or hotter is most likely _NOT_ the PMCC's sweet spot and it would be reasonable to assume/guess the unit is terminating the charging session due to thermal overload due to insufficient cooling and/or thermal tolerance design.

if my speculation is correct - this is a separate but related thermal weakness with regards to the PMC+/PMCC that is not directly related to the "runs hot by design - perfectly normal - nothing to see here" NEMA 14-50/6-50 power supply cable issue…

this would bring the set of known issue for the PMC+/PMCC to be summarized as follows:

• power supply cables run hot by design - this is expected and normal - don't pair the PMC+/PMCC with wimp ass NEMA sockets
• the PMC+/PMCC are very very intolerant of any grounding issue
• there is mounting evidence that the PMC+/PMCC will overheat in normal "summer" conditions and therefore may not complete charging session during high ambient temperature conditions
• perfect normal PMC+/PMCC unit that behaved fine in the past seem to degrade and become more finicky over time - failing in circumstances where they previously worked flawlessly - they seem to not age very well - but there is a lack of hard evidence in this space…
• we know that Porsche would love you to run their unit at 50% capacity (4.8 kW/20 amps) and that avoids all this nasty thermal overload and we may or may not be a good EVSE nonsense - honeslty what's wrong with it tkaing 18 hours to fully charge your Taycan
• the first hint of trouble with the PMC+/PMCC unit Porsche is ill-equipped to provide any meaningful customer support or diagnostics and will leave you hanging as a customer
• the PMC+/PMCC have a very very spotty record of being able to successful charge non-Porsche EV's
• the PMC+/PMCC remain very very very expensive EVSE's vs. higher quality more robust alternative EVSE's for North America - virtually no one can recommend the PMC+/PMCC as an EVSE if we all had to pay full price, and only the "included" PMC+ is worth considering, $1120 for the PMCC is grossly expensive vs. higher quality non-Porsche alternatives.

my conclusion/opinion remains (North American PMC+/PMCC):

• Porsche is not necessarily wrong to claim their units "behave correctly" - Porsche appears comfortable with the operating temperatures the unit achieves in normal operation (if it's coupled with a high quality NEMA socket)
• I think it's pretty clear however the PMC+/PMCC are not the BEST EVSE's for a qualty 9.6 kW EVSE in North America
• Porsche steadfastly to date refuses to acknowledge there is any design short fall - all limitations/faults are apparently "expected" given their design goals and that leads one to conclude there are no "changes" recalls, or adjustments forth coming.
• if you want a high quality EVSE with greater resilience, lower normal operating temperatures and demonstrably operate more robustly both electrically and thermally you need to seriously consider non-Porsche EVSE alternatives.
• don't buy the PMCC - spend 1/2 the money or less on something else that is better quality.

the best advice going on 3+ years now - continues to be:

At the first sign of trouble abandon your PMC+/PMCC and source one of many excellent alternative EVSE's and your EV ownership experience will improve - vs. attempting to successfully resolve most any issue involving a PMC+/PMCC. You'll be happier with a non-Porsche EVSE charging your Taycan.

I weep for the impending roll out of Macan EV's and the 100% foreseeable and avoidable high volume problems that will manifest with the PMC+/PMCC attempting to charge a much larger fleet of Macan EV's…this could be painful to watch.

because of the related nature of this problem - but not the direct known power supply cable problem - this thread has been added to the "PMC+/PMCC" ultimate guide…

the best advice however (in my opinion) remains:

Use the included/free PMC+/PMCC with your Taycan - until it gives you trouble - if it doesn't give you any trouble - great - keep using it! but at the first sign of trouble - abandon it and get a high quality alternative - you'll be happier in the end.

 

[EddieD]

there is a bit more nuance to this but you have the broad outline mostly intact

• Porsche is not wrong about low quality outlets - cheap NEMA sockets are not designed to provide 9.6 kW for multiple hours on end daily, weekly, monthly with _ANY_ EVSE - only high quality ceramic/commercial/industrial quality NEMA outlets should be used with _ANY_ EVSE including Porsche's and others…see Porche's document for the correct part numbers
  • the $12-$35 leviton NEMA 14-50 outlet from homedepot/lowes is _NOT_ the correct choice to provide power for _ANY_ EVSE
• Porsche's NEMA 14-50/6-50 power supply cables use AWG 10 wire - which for 40 amp continuous loads will get a bit toasty by human standards - but is completly safe given Porsche's choice of 105C temp-rate insulating plastic. There are no reports that I'm aware of where Porsche's power supply cable demonstrates any systemic failure or safety issue
  • Porsche's power suppy cable getting hot sucks, is no good, and 100% un-necessary - but it's not unsafe it just runs hotter than people expect and vs. other competitive/alternative EVSE's
• The combination of a correct-safe power supply cable that runs "hot by design" with a low quality outlet that is not designed to handle hours of thermal stress is a bad combination, but it's difficult to pin blame down in this case. Porsche is allowed to say "use better components" our stuff is fine, but it would also be possible for Porsche to ship an alternate design that places less thermal stress on related non-Porsche components involved in a residential home charging circuit.
• I suspect, but do not know for a fact - the charging problems in this case honestly has _NOTHING_ to with the power supply cable in this case, but rather the PMC+/PMCC unit itself - my experience with my PMCC's is they are finicky/temperamental beasts and easily give up on a charging session at the first sign of trouble - I would not describe them as robust and resilient. My suspicion is this is simply a less frequent thermal problem, that is unrelated to the powersuppy cable (although it can't be helping) where the PCM+/PMCC unit itself has problems operating at full capacity when there are high ambient termperatures (can you same summer? I knew you could). So the PMCC unit quietly stops the flow of power once it reaches a predetermined thermal temperature so that it does not overheat. Porsche would most likely characterize this as a "safety" feature in that the unit is shutting itself down in an orderly an controlled manner to preserve it's operational integrity and avoid failure/melting/burn-out due to thermal stress.
  • attempting to operate Porsche's EVSE in a high ambient temperature environment 90F or hotter is most likely _NOT_ the PMCC's sweet spot and it would be reasonable to assume/guess the unit is terminating the charging session due to thermal overload due to insufficient cooling and/or thermal tolerance design.

if my speculation is correct - this is a separate but related thermal weakness with regards to the PMC+/PMCC that is not directly related to the "runs hot by design - perfectly normal - nothing to see here" NEMA 14-50/6-50 power supply cable issue…

this would bring the set of known issue for the PMC+/PMCC to be summarized as follows:

• power supply cables run hot by design - this is expected and normal - don't pair the PMC+/PMCC with wimp ass NEMA sockets
• the PMC+/PMCC are very very intolerant of any grounding issue
• there is mounting evidence that the PMC+/PMCC will overheat in normal "summer" conditions and therefore may not complete charging session during high ambient temperature conditions
• perfect normal PMC+/PMCC unit that behaved fine in the past seem to degrade and become more finicky over time - failing in circumstances where they previously worked flawlessly - they seem to not age very well - but there is a lack of hard evidence in this space…
• we know that Porsche would love you to run their unit at 50% capacity (4.8 kW/20 amps) and that avoids all this nasty thermal overload and we may or may not be a good EVSE nonsense - honeslty what's wrong with it tkaing 18 hours to fully charge your Taycan
• the first hint of trouble with the PMC+/PMCC unit Porsche is ill-equipped to provide any meaningful customer support or diagnostics and will leave you hanging as a customer
• the PMC+/PMCC have a very very spotty record of being able to successful charge non-Porsche EV's
• the PMC+/PMCC remain very very very expensive EVSE's vs. higher quality more robust alternative EVSE's for North America - virtually no one can recommend the PMC+/PMCC as an EVSE if we all had to pay full price, and only the "included" PMC+ is worth considering, $1120 for the PMCC is grossly expensive vs. higher quality non-Porsche alternatives.

my conclusion/opinion remains:

• Porsche is not necessarily wrong to claim their units "behave correctly"
• I think it's pretty clear however the PMC+/PMCC are not the BEST EVSE's for a qualty 9.6 kW EVSE in North America
• Porsche steadfastly to date refuses to acknowledge there is any design short fall - all limitations/faults are apparently "expected" given their design goals and that leads one to conclude there are no "changes" recalls, or adjustments forth coming.
• if you want a high quality EVSE with greater resilience, lower normal operating temperatures and demonstrably operate more robustly both electrically and thermally you need to seriously consider non-Porsche EVSE alternatives.
• don't buy the PMCC - spend 1/2 the money or less on something else that is better quality.

the best advice going on 3+ years now - continues to be:

At the first sign of trouble abandon your PMC+/PMCC and source one of many excellent alternative EVSE's and your EV ownership experience will improve - vs. attempting to successfully resolve most any issue involving a PMC+/PMCC. You'll be happier with a non-Porsche EVSE charging your Taycan.

I weep for the impending roll out of Macan EV's and the 100% foreseeable and avoidable high volume problems that will manifest with the PMC+/PMCC attempting to charge a much larger fleet of Macan EV's…this could be painful to watch.

because of the related nature of this problem - but not the direct known power supply cable problem - this thread has been added to the "PMC+/PMCC" ultimate guide…

the best advice however (in my opinion) remains:

Use the included/free PMC+/PMCC with your Taycan - until it gives you trouble - if it doesn't give you any trouble - great - keep using it! but at the first sign of trouble - abandon it and get a high quality alternative - you'll be happier in the end.

Thanks so much for your very complete discussion of the problem. I suspect in my situation you’re probably absolutely right that the issue is the PMCC itself rather than the cable. Just a technical question, if the cable thickness were increased, would that decrease the stress on the PMCC so it would be less likely to overheat and shut
down? Interestingly, prior to the insane high temperatures this summer, I did put a very low tech solution, a fan blowing on the PMCC and at least at reasonable hot temperatures that did solve the problem. I have no problem charging my Taycan anytime other than the hot summer months. Do you have a recommendation for a different charger to purchase that is reliable and not priced insanely. Thanks so much for all your extensive information.

 

[utsteve98]

Thanks all for the info. I suspect it’s just gonna be the high heat in my garage in south TX that isn’t helping. Time to find a new charger.

 

[DerekS]

Thanks all for the info. I suspect it’s just gonna be the high heat in my garage in south TX that isn’t helping. Time to find a new charger.

I'm a big fan of Wallbox. And it integrates with my app Chargey making it effortless to track your home charging costs.

 

[daveo4EV]

Thanks so much for your very complete discussion of the problem. I suspect in my situation you’re probably absolutely right that the issue is the PMCC itself rather than the cable. Just a technical question, if the cable thickness were increased, would that decrease the stress on the PMCC so it would be less likely to overheat and shut
down? Interestingly, prior to the insane high temperatures this summer, I did put a very low tech solution, a fan blowing on the PMCC and at least at reasonable hot temperatures that did solve the problem. I have no problem charging my Taycan anytime other than the hot summer months. Do you have a recommendation for a different charger to purchase that is reliable and not priced insanely. Thanks so much for all your extensive information.

Enphase/ClipperCreek
Tesla J-1772 Wall Charger
Wallbox
ChargePoint
Autel

 

[tchavei]

I keep my PMMC in the trunk in case a hotel doesn't have charging facilities (happened once so far). If I were to charge at home (I'm not) I would get a high quality wall charger though, albeit here in Europe, with 220V (half the amperage needed) even in trifasic mode (660V, 16A =10.5kW), the PMMC seems to give no issues at all (has been always cold to the touch)

 

[daveo4EV]

I keep my PMMC in the trunk in case a hotel doesn't have charging facilities (happened once so far). If I were to charge at home (I'm not) I would get a high quality wall charger though, albeit here in Europe, with 220V (half the amperage needed) even in trifasic mode (660V, 16A =10.5kW), the PMMC seems to give no issues at all (has been always cold to the touch)

the european verions of PMC+/PMCC (for what ever reason) have experience demonstrably fewer issues vs. North American versions.

I'm not privy to any actual differences (other than the obvious supply cables) - but regarding the internals I've not received any description/details of internal differences (if any).

but none of my opinions/observations relate to any non-North American version of PMC+/PMCC

I believe there is sufficient evidence that my summary of "issues" for the North American version is accurate - I welcome corrections (and believe I always have).

 

[daveo4EV]

Thanks so much for your very complete discussion of the problem. I suspect in my situation you’re probably absolutely right that the issue is the PMCC itself rather than the cable. Just a technical question, if the cable thickness were increased, would that decrease the stress on the PMCC so it would be less likely to overheat and shut
down? Interestingly, prior to the insane high temperatures this summer, I did put a very low tech solution, a fan blowing on the PMCC and at least at reasonable hot temperatures that did solve the problem. I have no problem charging my Taycan anytime other than the hot summer months. Do you have a recommendation for a different charger to purchase that is reliable and not priced insanely. Thanks so much for all your extensive information.

regarding your question about the cable and such - I think all that can be said is below in bullets in no particular order:

• it might make a difference
• we honestly can't know - I certainly don't know
• I'm not a EE or thermal engineer
• I think it's safe to say the power supply cable's nominal operating temperatures isn't helping the situation - but it may or may not be a significant factor - we just don't know
• but my honest guess would be this problem's on the PMCC unit independent of the power supply cable's normal operating temperatures
• the PMCC unit is big bulky and heavy - it's density seems substantial - I'm pretty sure it's an excellent heat soak(in terms of retaining heat) - it seems to have a lot of thermal mass - it may not be sufficiently designed to shed it's internal heat in high temp ambient conditions
• but honestly how the thermals of the power cord and the PMCC unit itself interact and the thermal characteristics of the PMCC unit are largely unknown - but I don't believe they have demonstrated thermal resilience in summer operating temperatures…

over the years I've used Tesla's excellent, small, light 40 amp/9.6 kW Tesla Corded Charger ($200) laying out in the sun in a parking lot/paddock in 100F+ conditions to charge multiple EV's - and it has run flawlessly in these extreme conditions - I believe we could all predict the outcome of what would happen should we try the same with a PMC+/PMCC unit - you'll have opportununity on Aug 16th - it's supposed to be 109F in Willows, CA - anyone wanna trundle up to Thunderhill and attempt to charge their Taycan with a PMCC unit at say 1:45 pm in the paddock in direct sunlight laying on the black asphalt running at a full 40 amps?

I'm going to speculate the PMC+/PMCC power cable's operating temperature is not a factor here - I do not think there is enough thermal transfer from the cable to the PMCC unit to explain why the PMCC unit is shutting down (the PMCC doesn't need the cable's assistance to overheat - it can do it all on it's own) - if the power cable was a factor Porsche might consider redesigning it - but they have clearly stated the power cable's normal operating temperature is not a defect and is normal - they have said so in writing - so obviously their engineers designed the associated PMC+/PMCC unit to tolerate the power supply cable's normal operating temperatures…right?

Porsche's quote from their document for your reference:

Caution
The surface of the charger and associated equipment can become very hot under normal use. This is normal and not an indication of a defect in the charger. Observe the operating instructions provided with the charger, particularly the warnings and safety instructions.

any temperatures achieved by the PMC+/PMCC and it's associated components is "normal" and "expected" - not a defect - so it must be good right?

 

[bj33813]

I had the same issue, and a 2 finger reboot cleared it. Seems my NAV had a destination that was close to where the car was at the time, so it thought it had completed it's journey. I had neglected to turn off the NAV.

 

[j_scheetz]

I have fixed my charger so that it will not overheat when charging at 40 amp. I think the issue is that the wire that Porsche used for the pigtail and the cable to the car are 10 awg and rated for 40 amps at 194 degrees. I do not think the charger or car like 190 degrees F.

After charging for 3 hours at 40 amps in 95 degrees , I have measured the temperature at the car receptacle at over 170 degrees on the outside of the wire and over 200 degrees at the receptacle pins.

I re-wired the pigtail with #8 awg wire and bought a #8 awg extension cable to connect to the car. This dropped the temperature in the car receptacle from 218 degrees to 141 degrees.

My plug from the pigtail into the wall receptacle now runs at 112 degrees after 3 hours since the wire does not get as hot and does not heat the plug or charger as much.

I still have higher temp at the charger where the pigtail connects into the charger since I could not change the wire size in the connector to the charger.

The fix would be for Porsche to change the pigtail and the wire to the car with #8 awg wire. The larger wire flows the 40 amps with far less heat.

Sponsored