I’ve been NERFed!!! Slower charging after OTA software update

[RED!]

So my car asked me to do an OTA update. Being a good software security lemming I accepted the update.

Now I charging at 8.6 kWh vs the 10.5 I used to get!!!

This not only pisses me off, but I just spent extra money to install 60A lines and 48V chargers (x2). I feel like Porsche should give me money back if it’s a result of the update. It’s possible that it’s something else since I’ve also noticed my range has dropped by 20+ kms same if not warmer temps.

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[SergeyIndy]

Gotta be kidding, I think this is coming to all. Could you provide an update on what that OTA looked like so we can be on a look out and possibly decline. I am still charging at 11kW rate.

 

[W1NGE]

Was it this?

https://www.taycanforum.com/forum/threads/wss4-high-voltage-charger-ota-received.32830/

 

[whitex]

If your original build spec sheet said 11kW, demand a repair under warranty. If they refuse, sue for not repairing under warranty. In some places, like in California, you could even lemon the car (force the manufacturer to buy it back) if they cannot repair it.

Of course, if your build sheet said 9.6kW, then Porsche will claim 11kW capability was a bug they fixed.

 

[RED!]

Yes, I have an 11kw charger on my build sheet. The max power my charger put out is 9.85 kw so the car only took/got 8.something.

 

[RED!]

This was last Saturday, same charger

 

[gnr3312]

Is this a report specific to your charging unit? I’m trying to see what speed my 4S charges at home.

 

[daveo4EV]

Is this a report specific to your charging unit? I’m trying to see what speed my 4S charges at home.

if we're going to make any progress on this issue terminology and precise usage is going to be required.

there are two components at work here:

1. the Onboard charger which is a factory installed unit (OBC) - this is the AC/DC converter installed at the factory and is responsible for charging the high-voltage battery from an external 120/240V AC power source
   1. there are two types of units - 11 kW unit and a 22/19.2 kW unit
2. the external EVSE (common referred to as a "charger" but that's incorrect) - the EVSE provides a raw 120V(L1) or 240V(L2) AC power feed to the vehicle's OBC's

Porsche is deploying software that changes the maximum current/amps their OBC allows in North America from an EVSE…

the screens shown in posts #5 & #6 are reports from @RED! EVSE - these screen shots show the charging session from the EVSE point of view - and clearly demonstrated that the EV in question used to request/allow a full 48 amps (11 kW) and post software update now only requests/allows 9.6 kW (40 amps)…the EVSE doesn't lie, it's too dumb and passive in this scenario as it's just a simple raw AC power "pump" - nothing more - nothing less - and simply provides the power/current as requested by the Vehicle/OBC…

with the latest software Porsche has nerf'd the Taycan's OBC in North American to a maximum charge rate of 240V/40 amps (50 amp breaker) which is nominally 9.6 kW of raw AC power…this will translate to an in vehicle display of ~8.x kW displayed by the vehicle/app during charging

let's be clear on our terminology usage

1. OBC - Taycan's internal component that controls charging the battery
2. EVSE - external power supply that plugs into the vehicle to deliver the raw AC power "feed" under control of the OBC and it's associated software.

the OBC maximum charge rate is being adjusted/nerfted by Porsche from a max rate of 11 kW (240V @ 48 amps nominally) to a maximum rate of 9.6 kW (240V @ 40 amps nominally)…

so far Porsche has failed to disclose this change as part of any software update and failed to provide their rational as to why they making this change.

Porsche North American has historically had a confusing policy of the maximum charge rate of the OBC of the Taycan often confusing two separate maximum charge limits common in North American

1. maximum charge rate of the OBC (9.6 kW or 11 kW)
2. maximum charge rate of any mobile NEMA plug based North American EVSE - strictly 9.6 kW - there is no such thing as a _MOBILE_ North American EVSE that can do 11 kW
   1. EVSE's that provide more than 9.6 kW _MUST_ be hardwired in North America due to regulations/building-codes - therefore there is NO SUCH THING as a MOBILE 11 kw (or greater) EVSE in North America
   2. Porsche MOBILE EVSE(s) PMC/PMC+/PUC/PMCC can therefore provide a maximum raw AC feed of 9.6 kW…if you don't believe me - check the back of _ANY_ North American Porsche EVSE (Audi too!!) and it's clearly labeled 40 amp and 9.6 kW in the small print/specifications clearly labeled on the back of the Porsche mobile units…
   3. Porsche Wall Charger Connect (PWCC) is a hardwired EVSE sold in North American - and is adjustable from 15 to 100 amp breakers - and provides available raw AC power depending on configuration from 1.44 kW to 19.2 kW
   4. there are several excellent non-Porsche EVSE that provide a similar range of raw AC power for any J-1772/NACS based EV.
   5. again _ALL_ North American _MOBILE_ EVSE(s) are limited to 9.6 kW maximum power due to building codes and electrical requirements.

this "confusion" has made it very very difficult to nail down the actual expected limits for the Taycan in North American - which is how they are getting away with this change…

at different points in time Porsche's 4 main EV/Hybrid (Taycan, Macan EV, Cayenne Hybrid, Panamera Hybrid) products have listed:

• the maximum charge rate as 11 kW - Macan EV/Taycan 2023 and later
• the maximum charge rate as 9.6 kW
• the maximum charge rate of their _MOBILE_ EVSE as 11 kW (impossible see above)
• the maximum charge rate of both the vehicle/OBC and mobile EVSE as 11 kW

right _NOW_ the 2024/2025 Cayenne and Panamera Hybrid's list the OBC as 11 kW and those vehicle's can actually charge at 11 kW - so Porsche's hybrid products can charge faster than their two dedicate EV's (Taycan & Macan)…

the 2024/2025 Macan EV had 11 kW OBC as a technical specification for over 1+ years - but the site was updated - to my knowledge prosche never shipped a North American Macan EV that allowed more than 9.6 kW charge rate even though the specifications wed site listed 11 kW…

in North American EVSE's can provide a range of raw input power from approximately a low of 700 watts to a maximum of 19.2 kW - common EVSE capacities are 3.6 kW to 19.2 kW…

_ANY_ EV when plugged into an EVSE will limit the maximum charge rate to match the vehicle's OBC limits - even if the EVSE can provide more raw power…

the EVSE is NOT a charger - it's an external power source that advertises it's maximum available power to the vehicle's OBC and it's associated software. The vehicle's OBC and software decides on how much power it's going to draw from the EVSE…the EVSE is a "dumb" pump in this scenario and has no control over the current draw from the OBC…

Porsche is neutering their North American OBC software to a maximum charge rate of 9.6 kW…even if the EVSE can provide more raw power - they are allowed to do this and that is the role of an OBC - but they are downgrading the maximum charge rate with out disclosure.


Porsche DEMONSTRATED confusion between OBC and EVSE limits is either willful or simply ignorance but it's NEVER been clear PCNA actually understands the two different limits and they have often times published inaccurate or misleading technical specification in this area - it pure speculation as to why/how Porsche North America continues to lack clarity and precision in this space.

this confusion translates to the dealer/service network as they are equally confused and often time provide inaccurate or misleading information regarding EV charging limits and the relationship of OBC and EVSE's…

One dealer/service manager told me flat out Taycan can not charge at more than 9.6 kW, and there is NO such thing as an EVSE than can do more than 9.6 kW. I then showed him the 19.2 kW OBC factory option and the Prosche Wall Charger EVSE both of which are more than 9.6 kW - and he had no response…and said "he'd have to check on that"…

I've personally since 2019 found Porsche's lack of clarity in this space coupled with their continued obsession with eFuel's to be a bellwether for their lack of "true belief" in this whole EV thing - being an engineering focused company they normally sweat the details and get them right - but they have historically been super sloppy in this space and their EV charging game in North America as been weak sauce - their failures to engage, educate and be precise and accurate in this space quite simply bely's their true engagement on EV's in general - which is to say they really really would rather not do the EV thing at all…

The Cayenne EV continues this tradition of conflicting and confusing information:

• published maximum wired EV charge rate 9.6 kW
• published maximum _WIRELESS_ charge rate 11 kW
• published maximum OBC charge rate 9.6 kW
• optional OBC 19.2 kW as a factory option (discontinued for Taycan, not available for Macan)
• they have not answered if you can charge via AC power on the single native NACS charging port on the North American Cayenne EV…
  • which is going to be an odd duck - in that you can only fastDC charge with the NACS port, and only L1/L2 AC charge with the J-1772 port
  • this is quite simply sloppy engineering since NACS allows either FastDC or AC charging via a single port, but that requires engineering an OBC that can accept both AC/DC power as input and intelligently adapter based on what type of EVSE is being plugged …
  • Porsche appears to lack the engineer skills/willingness to provide a AC/DC adaptable OBC and is going to limit DC charging to one side of the vehicle, and AC charging to the other side in North America
    • I can guess/know why they are doing this - because once again they are only grudgingly engaging on this EV thing and they probably made the switch to NACS 1/2 way through the Cayenne development process and had to compromise the AC/DC adaptability due to how far along they were in the whole design/production process…
  • current Macan/Taycan allow AC or DC charging on one side, AC only on the other side…

so my Cayenee's EV's OBC is limited to 9.6 kW? but I can charge it wirelessly at 11 kW?? But if I plug in my 80/100 amp 19.2 kW Porsche Wall charger to my Cayenne I'm limited to 9.6 kW? But there is as factory option for a 19.2 kW OBC, but the 19.2 kW OBC for Taycan has been discontinued even as a service part for the Taycan due to it's legendary unreliability…

I have NEVER found similar levels of confusion for EV charging limits with _ANY_ other EV vendor…

 

[RED!]

Excellent overview, that said, two questions:
1) “they are allowed to@ Nerf my OBC??? What permits them to?
2) my car is a 24, so it falls outside of your range for “will get nerfed”, so why me? I assume the answer is that it’s all the same OBC so everyone is getting the chop

 

[daveo4EV]

Excellent overview, that said, two questions:
1) “they are allowed to@ Nerf my OBC??? What permits them to?
2) my car is a 24, so it falls outside of your range for “will get nerfed”, so why me? I assume the answer is that it’s all the same OBC so everyone is getting the chop

Porsche has always controlled the software that controls the OBC - this is no different to them than changing the configuration for high beam brightness, fuel flow change for engine idle or any other ECU software that is part of all modern vehicle's

it's their OBC, it's their OBC software and it's no different than any other ECU (Electronic Control Unit) software updates - prosche routinely updates ECU software across their entire fleet of vehicle's for various reasons: safety, bugs, warranty, regulations, etc…

I believe it's Porsche's intention to update the "fleet" of Taycan for North America to get them all down to max charge rate of 9.6 kW…

my personal speculation as to why: is that the 11 kW limit was always intended to only be supported in Europe's 3-phase AC power environment. 240V power in North American is handled differently than 240V power in Europe - single phase/split-phase vs. 3 phase in Europe.

Porsche's OBC reliability is problematic - and the unit fail quite often - this a problem for customers and a problem for Porsche's warranty costs - it's also been speculated with data that Porsche's OBC design lacks "robustness" - other EE's have reverse engineered the OBC and found it "lacking greatness" in terms of high power robustness…YMMV

I believe Porsche is nerf'ing the North American OBC's to limit/mitigate warranty claims because they know the OBC's internal design isnt' quite up to snuff and has failure modes related to power flow…

in North America 11 kW is 48 amps of 240V power flowing through the OBC and taxing the components
in Europe 11 kW is 16 amps of 240V/3-phase power flowing through the OBC and taxing the components

16 amps is quite a bit less than 48 amps and I don't think the OBC is robust enough for Porsche's comfort to deal with 48 amps of power taxing the components.

as to why/how they can "get away from it" - you'd first have to get them to agree to the following:

1. they they are doing this at all
2. what was the original intended specification for your 2024 Taycan?
3. disclose which software update "did it"

Porsche has updated your vehicle to the recommended software from Porsche Germany. Obviously this change was intentional on their part. This is no different that the ECU update I got for my 2021 Cayenne TurboS eHybrid to change the engine thermostat temperature tolerances to avoid failure of the thermostatic switch, and no different that the software update for 2024 Macan EV that "fixed" a headlight high-beam issue that violated North American high-beam brightness regulations…

Porsche owns/provides the OBC software, it's theirs to update as they see fit.

 

[daveo4EV]

Excellent overview, that said, two questions:
1) “they are allowed to@ Nerf my OBC??? What permits them to?
2) my car is a 24, so it falls outside of your range for “will get nerfed”, so why me? I assume the answer is that it’s all the same OBC so everyone is getting the chop

my range is for "thought process only" - only Porsche _KNOWS_ the range of vehicle's they intend to do this for - and they have not disclosed how, why they are doing this and what criteria - maybe it's only being done to Taycan's that have OBC's made between X & Y date from supply change vendor "billy"…

I can only SPECULATE what and why Porsche is doing this - ONLY they know - and they are not posting on this forum - just like only they know why they are making this change, and what range of Taycan VIN's it will affect…yours clearly was in the group of Taycan's that Porsche intended to get this change of behavior. Only porsche knows if this is "all North American Taycans" or "some North American Taycans"

but remember you probably can't even get them to admit it was ever 11 kW or should have been 11 kW…so in their corporate mind - it is not a change.

 

[daveo4EV]

this thread and like all road lead back to Rome…

there is nothing new in this thread that isn't already covered in these existing threads:

https://www.taycanforum.com/forum/t...-charger-48-amps-not-max-9-6-kw-40-amps.1793/
https://www.taycanforum.com/forum/threads/level-2-charging-rate-with-a-50-amp-capacity.29987/

@Administrator I'll humbly suggest this thread be closed - to avoid have 3 ongoing conversations about this core issue…but I'm not emphatic about it.

but the other 2 threads have all the history and evidence on this topic.

@RED! I'd suggest you post a "me too!" referencing this thread on either of the 2 pre-existing threads as you are another data point about the fact that Porsche is actually doing this - and your before/after EVSE reports as to the AC power current draw are indicative of the facts of the situation and that we're not "just making this up".

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