On-board charger 😒…..???

[carlos vilarinho]

It's been quite a while since I've been here because fortunately I haven't had any problems with my Taykan Cross Turismo until yesterday, and it's a problem already reinforced by Porsche in the Taykan models between 2022 and 2024. I'm going to try to resolve it outside of Porsche because the car is currently out of warranty and I also don't intend to pay a fortune for a repair that I can do for less than half the price. Besides fixing my OBC unit, at least they could replace the damaged transistors (MOSFETS) with new reinforced ones and not replace the unit with a new one, risking it returning to the same problem in a while. Has anyone replaced this unit before…???? Another thing, my car didn't start and no error appeared on the instrument panel, everything is normal, so it's not charging…

Summary of the Problem:

• Slow charging on alternating current (at home, 11 kW public socket, original Porsche Mobile Charger Plus charger) — the charging light is initially white (communication established) and then red after a few seconds (the (Car rejects the cartridge). The car does not start charging.

• Direct current fast charging (120 kW public charging station) — works perfectly, without problems.

• No warning message on the instrument panel.

• The problem started after using a non-original charger (Green Volt). I returned it and bought an original Porsche charger, but the same error persists.

• I have already ruled out the possibility of it being the house's electrical network — the same thing happens with public chargers.

My suspicion (based on technical analysis):

• The on-board charger (OBC) likely has an internal hardware fault. Specifically, a short circuit in the internal MOSFETs/transistors of the OBC board.

• A white light indicates successful communication between the car and the charger. A red light indicates that when the car tries to activate the internal rectifier circuit, the board detects a hardware fault and blocks the process for safety. • This is a known problem reported by Porsche — the on-board computer (OBC) can fail due to power surges or damage to internal components.

• The car normally runs on direct current (which bypasses the OBC), but fails on alternating current (which passes through the OBC).


Has anyone else experienced this? Given that I still haven't received any warnings (e.g., "Electrical system error, inspection required"), could the problem really be with the on-board computer (OBC)? Or could it be a fuse or something similar? I'll run the PIWI tomorrow to check for error codes…….

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[claus]

You have the 22 kW OBC ? They have an internal design fault and often burns a component inside. Cannot be repaired - only a new OBC will solve your problem. The DC charging goes straight to the HV battery - that’s why you can easily charge elsewhere. The OBC fault has nothing to do with you using a non-original AC charger.

 

[Bennachie]

22 or 11 - either - it is toast. Think yourself lucky it has not blown the EVSE trip. OBC is for AC only. It does not affect DC charging.. No dash warnings. There will be lots of codes though. Book it in Dano!

 

[carlos vilarinho]

[SOLVED] AC Charging Error / Red Light on Taycan (It wasn't the OBC!) Guys, I'm leaving this report here because I'm sure that one day this will save a lot of headaches and euros for someone in the group. A few days ago, my Taycan started showing an error with a red light on the plug when charging at home (Slow AC Charge), but it charged perfectly at fast charging stations (DC). The car didn't give any warning on the dashboard, so we only understood what was happening after carefully analyzing the error codes in PIWIS 3. It had error B200000 (AC Charger – function restriction) and communication failures in the Gateway (U116C00). At first glance, normal panic: "The internal charger (OBC) burned out". I'll share these detailed error codes in the group later. So, what was the problem? The real cause was the windshield replacement done a little over a week ago, where the front camera (ADAS) located in the rearview mirror wasn't calibrated. The car's logic (which is super complex): The dashboard remained clear because the camera itself isn't broken, just slightly misaligned (data coherence error). For about 9 days, the Gateway tolerated the deviation, attempting to recalibrate while in motion. At the end of that time, it assumed the error was static and blocked the CAN network for safety. Since the active aerodynamics and headlights depend on the camera, the Gateway entered "protection mode" and restricted the functions of the home charger (OBC), blocking slow charging to protect the electrical system. Fast charging (DC) continued because it bypasses the OBC and goes directly to the battery. Resolution: The OBC module is 100% and in perfect health. The car will go to a specialized workshop tomorrow to align and calibrate the front camera with Porsche's specific ADAS panels and targets. Once the camera is calibrated, the Gateway will release the network, the errors will be cleared, and slow charging will resume. If your Taycan stops charging at home and flashes red (especially if you've recently worked on the windows, suspension, or front sensors), don't panic: the OBC might be fine and it could just be a preventative software lock!

 

[Bennachie]

Good to know! Weird German logic though...... misaligned camera = no AC charging...

 

[carlos vilarinho]

The car did exactly what it was programmed to do: it prioritized safety and protected the electronic and thermal components, which are functioning at 100% [oemdtc.com]. Instead of letting the system operate blindly and risking overheating due to a lack of communication with the active front aerodynamics, Porsche's engineering team chose to proactively disable the convenience function (domestic slow charging) [oemdtc.com]. It's a complex but brilliant logic, because it prevented its internal charger (OBC) from suffering any real wear and tear.

 

[carlos vilarinho]

Loll

 

[r553]

My car has the B200000 code also but charges fine. The dealer did not find anything wrong....

 

[carlos vilarinho]

Hello everyone,


I would like to know if anyone here has successfully replaced the OBC (On-Board Charger) on a Porsche Taycan with a genuine Porsche used OBC taken from another Taycan, with exactly the same Porsche part number as the original unit.


In my case, the car suddenly stopped charging on AC. There were no warning messages on the dashboard, the car drives perfectly normally, and DC fast charging still works without any issues.


The original OBC still communicates with the PIWIS diagnostic system, but it appears to have suffered an internal failure (possibly EEPROM memory corruption or another internal electronic fault), affecting only the AC charging function.


Before purchasing another OBC, my auto electrician connected the car to the original PIWIS system to confirm the exact part number. Based on that, I bought a genuine Porsche used OBC removed from another Taycan, with the same Porsche part number as my original unit. The replacement module has been tested and is in good working condition.


My auto electrician now has access to the original PIWIS system and a Porsche Partner Network (PPN) account, and he is preparing to program, code and adapt the replacement OBC to my Taycan.


My questions are:

• Has anyone here successfully coded a genuine used Porsche OBC to a different Taycan?
• Was it necessary to remove component protection during the process?
• Did AC charging work normally after programming and coding?
• Were there any difficulties or unexpected issues during the replacement?

I would really appreciate hearing from anyone who has gone through this repair or has experience with replacing and coding a used OBC on a Taycan.


Thank you in advance!

 

[carlos vilarinho]

 

[Dee]

[SOLVED] AC Charging Error / Red Light on Taycan (It wasn't the OBC!) Guys, I'm leaving this report here because I'm sure that one day this will save a lot of headaches and euros for someone in the group. A few days ago, my Taycan started showing an error with a red light on the plug when charging at home (Slow AC Charge), but it charged perfectly at fast charging stations (DC). The car didn't give any warning on the dashboard, so we only understood what was happening after carefully analyzing the error codes in PIWIS 3. It had error B200000 (AC Charger – function restriction) and communication failures in the Gateway (U116C00). At first glance, normal panic: "The internal charger (OBC) burned out". I'll share these detailed error codes in the group later. So, what was the problem? The real cause was the windshield replacement done a little over a week ago, where the front camera (ADAS) located in the rearview mirror wasn't calibrated. The car's logic (which is super complex): The dashboard remained clear because the camera itself isn't broken, just slightly misaligned (data coherence error). For about 9 days, the Gateway tolerated the deviation, attempting to recalibrate while in motion. At the end of that time, it assumed the error was static and blocked the CAN network for safety. Since the active aerodynamics and headlights depend on the camera, the Gateway entered "protection mode" and restricted the functions of the home charger (OBC), blocking slow charging to protect the electrical system. Fast charging (DC) continued because it bypasses the OBC and goes directly to the battery. Resolution: The OBC module is 100% and in perfect health. The car will go to a specialized workshop tomorrow to align and calibrate the front camera with Porsche's specific ADAS panels and targets. Once the camera is calibrated, the Gateway will release the network, the errors will be cleared, and slow charging will resume. If your Taycan stops charging at home and flashes red (especially if you've recently worked on the windows, suspension, or front sensors), don't panic: the OBC might be fine and it could just be a preventative software lock!

So, first you say the OBC was fine and now your OBC has failed?
You'd better remove the above post cuz this is obviously nonsense.
A misaligned camera does not affect an OBC, that's just a coincidence apparently.

 

[carlos vilarinho]

So, first you say the OBC was fine and now your OBC has failed?
You'd better remove the above post cuz this is obviously nonsense.
A misaligned camera does not affect an OBC, that's just a coincidence apparently.

I understand why it may look confusing.


Initially, we thought the issue might be related to the recent windshield replacement because the fault appeared around the same time and the front camera still needed calibration. After the camera was calibrated, the problem remained exactly the same.


Further diagnostics with PIWIS showed that the issue was actually with the OBC. The original OBC still communicates with the car, but it appears to have an internal fault (possibly EEPROM-related), which prevents AC charging while DC fast charging continues to work normally.


So the camera calibration and the OBC failure were simply two separate issues that happened at roughly the same time. My earlier post reflected our initial assumption before the diagnostic process was completed.

 

[carlos vilarinho]

After further diagnostics, the issue is not a generic “OBC failure” code. The OBC stores B2000 – Internal Control Module Memory Check Sum Error, and the diagnostic software explicitly reports “Steuergerät defekt (EEPROM)” (control module defective – EEPROM). At times the controller also stops responding during diagnostics. The module still communicates intermittently, but AC charging no longer works, while DC charging and normal driving remain unaffected. This is why we are replacing the OBC with another genuine Porsche unit with the same part number.

 

[carlos vilarinho]

 

[carlos vilarinho]

Just one important technical note: although VCDS displays the description “Steuergerät defekt (EEPROM)”, this absolutely does not prove that the physical EEPROM chip is damaged. What the diagnostic shows is an internal memory failure of the module, which could be due to the EEPROM, Flash, microcontroller, or firmware. In practice, however, when this error occurs and the OBC loses its AC charging function, complete module replacement is a common solution.

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