Very slow DC charging

[chrisk]

I left the car parked for 3 weeks at 75% SoC not connected to a charger.

After I returned the range guessometer is way off. It shows very low range. But what is worse is DC fast charging is capped between 25 and 34w even when the SoC is under 60% and the battery is warm (29C/ 85F).
I have tried DC charging twice at two different EA stations and both time charging was very slow. The specific chargers work fine and provided 100+kw to other cars. Leaving the car locked overnight does not fix the problem.
My car was charging much faster at the same EA chargers before being left for 3 weeks.

Any clue of what might be happening? I am thinking of trying to rebalance the cells by charging to 100%. Anything else I could try? I really don't want to go back to the dealer unless the issue persists.

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[daveo4EV]

only a dealer/service tech can diagnose this issue - you don't have enough information.

 

[Nikon]

It may be charger's fault

 

[Legis]

Side note. My dealer said that if I am to leave the car for more than two weeks I need to have it connected to an external battery charger, otherwise the battery will discharge completely. You had yours untouched for three weeks?

 

[PrudentOcean]

Either the dealer is misinformed or you misinterpreted something he said. People have left their cars for several weeks without losing much SoC. Just keep your keys out of range and don’t constantly check the car’s status using the My Porsche app.

 

[daveo4EV]

Side note. My dealer said that if I am to leave the car for more than two weeks I need to have it connected to an external battery charger, otherwise the battery will discharge completely. You had yours untouched for three weeks?

your dealer is wrong.

 

[Dragon Tourniquet]

I left mine for 8 weeks without an issue. It was plugged in and at 50% charge (as recommended). Had the keys in a faraday cage away from the car, and didn't check via the app. It was fine when I returned.

 

[Wivenhoe]

I suspect the dealer was talking about the 12v battery not the traction battery. Even then, he appears to be wrong.

 

[Yves]

I left the car parked for 3 weeks at 75% SoC not connected to a charger.

After I returned the range guessometer is way off. It shows very low range. But what is worse is DC fast charging is capped between 25 and 34w even when the SoC is under 60% and the battery is warm (29C/ 85F).
I have tried DC charging twice at two different EA stations and both time charging was very slow. The specific chargers work fine and provided 100+kw to other cars. Leaving the car locked overnight does not fix the problem.
My car was charging much faster at the same EA chargers before being left for 3 weeks.

Any clue of what might be happening? I am thinking of trying to rebalance the cells by charging to 100%. Anything else I could try? I really don't want to go back to the dealer unless the issue persists.

Had mine sit 3 weeks not used and not hooked up to anything … all is ok, though I did not really fast charged it yet, except a 75kw charger and it got 80 kw so I guess all is good ….

 

[chrisk]

It may be charger's fault

It is certainly the car, not the charger. I have tried 3 different fast chargers of different providers (EA and EVGo) and I have the same issue. I waited and observed the chargers on the next car and they all provided 100+kw to them.

I will wait to do the battery recalibration procedure that I saw in a Taycan TSB and if that does not fix the issue I will take it to the dealer.

 

[Legis]

I suspect the dealer was talking about the 12v battery not the traction battery. Even then, he appears to be wrong.

Yes my comment was about the 12V battery, and I’ve found the two weeks reference several places online. Looking at this forum, it seems like this happened to @DHS earlier this year.

My dealer also told me that if this should happen, it would have to be towed as there is no way to recover once it is depleted.

https://www.macanevowners.com/forum...-to-vehicle-if-12v-battery-is-very-low.19277/

 

[Rocketair]

I left the car parked for 3 weeks at 75% SoC not connected to a charger.

After I returned the range guessometer is way off. It shows very low range. But what is worse is DC fast charging is capped between 25 and 34w even when the SoC is under 60% and the battery is warm (29C/ 85F).
I have tried DC charging twice at two different EA stations and both time charging was very slow. The specific chargers work fine and provided 100+kw to other cars. Leaving the car locked overnight does not fix the problem.
My car was charging much faster at the same EA chargers before being left for 3 weeks.

Any clue of what might be happening? I am thinking of trying to rebalance the cells by charging to 100%. Anything else I could try? I really don't want to go back to the dealer unless the issue persists.

I am in almost the exact situation.

- Had a Taycan 4S CT for the last 4 years, lease ended in June.
- Macan 4S was new July 1st. Drove ~500 miles the first two weeks, everything pretty normal. DC charged twice, once at EA, once not. Both similar to Taycan charge rates (between 100 and 200)
- Went on a 12 day trip, 75% SOC, unplugged. When I returned, the SOC had gone down 10%, which was pretty unexpected based on the Taycan experience and this forum's data.
- The range calc was immediately very wonky (maybe 85 miles range at 65%) which my first thought was that the range calc just re-calced using that 10% loss and zero miles driven.
- But now a month later and a few "fill ups" (none past 80%) and the range is still completely off, very very low. SOC seems accurate (i.e. i drove it down to under 10% once just to test, and it was fine, even though at say 30% it said I had 20 miles left, and I drove another 60mi over the next 20% and still say I had 15 at 8%...)
-Took another shorter trip last week (6 days) and SOC went down 5%. Again, seems so different than all other experiences of drain in the Macan EV that I have read about.
-Tried DC charging for the first time yesterday, and ran into the same thing you are seeing - maxed out at 33KW, tried another charger, same results.
-Android Auto (more specifically the internal Wifi connection) seems like it has issues ever since the trip, worked pretty flawlessly before (in my Taycan, it was hit or miss, so I often used the PCM - prior to the trip, I had committed to just always using AA, and it was solid.)

Theories:
- Something happened to the 12V while sitting that threw the software off.
- There is something set to on that the car really doesn't like to be left with for long periods of time and caused the drain and the software issue (nothign stands out, and i have been deep into the internal settings!)
- Maybe your car is around the same vintage (built in April/May/June) and something is specific to that software build/battery pack supply etc...
-I feel like that sitting drain data might be a key part of it.



I'm thinking next steps could be choose factory reset (never done, not sure if I am asking for trouble) or bring in to the dealer... But love to hear any thoughts!

 

[chrisk]

I am in almost the exact situation.

- Had a Taycan 4S CT for the last 4 years, lease ended in June.
- Macan 4S was new July 1st. Drove ~500 miles the first two weeks, everything pretty normal. DC charged twice, once at EA, once not. Both similar to Taycan charge rates (between 100 and 200)
- Went on a 12 day trip, 75% SOC, unplugged. When I returned, the SOC had gone down 10%, which was pretty unexpected based on the Taycan experience and this forum's data.
- The range calc was immediately very wonky (maybe 85 miles range at 65%) which my first thought was that the range calc just re-calced using that 10% loss and zero miles driven.
- But now a month later and a few "fill ups" (none past 80%) and the range is still completely off, very very low. SOC seems accurate (i.e. i drove it down to under 10% once just to test, and it was fine, even though at say 30% it said I had 20 miles left, and I drove another 60mi over the next 20% and still say I had 15 at 8%...)
-Took another shorter trip last week (6 days) and SOC went down 5%. Again, seems so different than all other experiences of drain in the Macan EV that I have read about.
-Tried DC charging for the first time yesterday, and ran into the same thing you are seeing - maxed out at 33KW, tried another charger, same results.
-Android Auto (more specifically the internal Wifi connection) seems like it has issues ever since the trip, worked pretty flawlessly before (in my Taycan, it was hit or miss, so I often used the PCM - prior to the trip, I had committed to just always using AA, and it was solid.)

Theories:
- Something happened to the 12V while sitting that threw the software off.
- There is something set to on that the car really doesn't like to be left with for long periods of time and caused the drain and the software issue (nothign stands out, and i have been deep into the internal settings!)
- Maybe your car is around the same vintage (built in April/May/June) and something is specific to that software build/battery pack supply etc...
-I feel like that sitting drain data might be a key part of it.



I'm thinking next steps could be choose factory reset (never done, not sure if I am asking for trouble) or bring in to the dealer... But love to hear any thoughts!

I am also an ex Taycan owner and I don't remember this behavior. I am trying to rebalance the battery now. I drove my car down to 20%. Left it unplugged for 12 hours and SoC went from 20% to 26% with the car just sitting in the garage unplugged. Then I charged it with an L2 charger up to 95% and let it sit for 12 hours unplugged. While the car was sitting unplugged at 95% I saw the range estimate gradually increased from 250 Miles 290 which is reasonable based on my driving. So this process has fixed the range estimate. I have not tested DC charging yet but I will report back once I do.

 

[Yves]

Maybe buy a dongle and use car scanner to get some more info out of the battery … maybe it gives a hint of what is wrong.

 

[chrisk]

Maybe buy a dongle and use car scanner to get some more info out of the battery … maybe it gives a hint of what is wrong.

I have already done that. No error codes or other obvious reason.

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