PCM Stuck on Porsche screen

[DrBusa]

Im in the uk, death screen been on for 2 days now. Did not resolve itself after an overnight lock. Removed the fuse waited for 5 minutes and added back

Sponsored

 

[Rik_CT4s]

Im in the uk, death screen been on for 2 days now. Did not resolve itself after an overnight lock. Removed the fuse waited for 5 minutes and added back

I have exactly the same since today. Oit of the blues.
I am on the new software 3892 for a few weeks now.

The screen, even after reset, even after >15min wait, does only show Porsche. Can't get in anymore.

Call porsche assistance?

 

[MrJones02]

I would try to disconnect the 12v battery, wait for 30 minutes or so, connect it again, makes everything do a clean reboot.

 

[Rik_CT4s]

I would try to disconnect the 12v battery, wait for 30 minutes or so, connect it again, makes everything do a clean reboot.

Isnt that sth to do by Porsche? Otherwise they may claim I temper with the system or so....i may call Porsche assistance and ask. Because normally owners do not disconnect the 12V system no? Just wondering if that is common practice.
Thank you

 

[Rik_CT4s]

Isnt that sth to do by Porsche? Otherwise they may claim I temper with the system or so....i may call Porsche assistance and ask. Because normally owners do not disconnect the 12V system no? Just wondering if that is common practice.
Thank you

Update just now.
Waited 20min+ and turned car on thereafter. It worked again, no error codes.
Weird!

 

[SergeyIndy]

Happening to me too a few times now recently. I just lock the car and let i be for a few hours then it comes back normal.

 

[DrBusa]

Step 1: At the top right of the screen, hold two fingers, and it should push you to the engineering menu. Select the full reboot option.



99% of the time, this should work, but if you are the 1% like me, then you should open the fuse panel on the passenger side. I think it's row 2, PCM fuse. Remove the fuse, wait 5 minutes, and plug it back in.

 

[whitex]

Porsche really should have just included a big red switch under the hood which shuts off both the traction (HV) battery and the 12V. The switch could be mechanically prevented from disconnecting if hood is closed just to avoid accidental disconnects. Then on page one of the user manual, print in big letters the IT motto - “Hello Porsche customer! Have you turned it off and back on again yet?”

I honestly considered adding such a reset switch to the car myself on a few occasions. It would come handy whenever software gets in a bad state, and after recoding the car.

 

[SergeyIndy]

Porsche really should have just included a big red switch under the hood which shuts off both the traction (HV) battery and the 12V. The switch could be mechanically prevented from disconnecting if hood is closed just to avoid accidental disconnects. Then on page one of the user manual, print in big letters the IT motto - “Hello Porsche customer! Have you turned it off and back on again yet?”

I honestly considered adding such a reset switch to the car myself on a few occasions. It would come handy whenever software gets in a bad state, and after recoding the car.

2026 Hyundai Sonata has that kind of switch labeled 12V battery reset.

 

[Jasper4S]

Porsche really should have just included a big red switch under the hood which shuts off both the traction (HV) battery and the 12V. The switch could be mechanically prevented from disconnecting if hood is closed just to avoid accidental disconnects. Then on page one of the user manual, print in big letters the IT motto - “Hello Porsche customer! Have you turned it off and back on again yet?”

I honestly considered adding such a reset switch to the car myself on a few occasions. It would come handy whenever software gets in a bad state, and after recoding the car.

I get your point, but that still feels like a band-aid solution. I'd rather see Porsche get their act together and deliver robust hardware and software. A stuck screen 6 years after model introduction is just....

 

[whitex]

I get your point, but that still feels like a band-aid solution. I'd rather see Porsche get their act together and deliver robust hardware and software. A stuck screen 6 years after model introduction is just....

Yes it is a band-aid, but a band-aid which seems required with today's evermore complex software. The increase in software system (all ECUs together) complexity means there is no way to thoroughly test all possible interactions, so returning back to known good cold start is a good band-aid to have in the toolbox.

 

[ebarron]

My 2026 PCM is stuck in circling endlessly. I've tried letting it sit overnight, still circling.

The only thing I've gathered from this thread is that disconnecting the 12V battery might help. Is that the current state-of-the-art reset procedure? Anything to be aware of - something more so than doing the same with a conventional ICE 12V battery?

 

[tbinmd]

only other option is to pull the fuse for the PCM. Battery disconnect the same as an ICE.

 

[ebarron]

Is that the passenger footwell? I know how to open the passenger side panel, but I don't think its there. Google says its behind the glovebox and to remove the cardboard/felt liner, but google also gets confused on driver side/passenger side.

 

[ebarron]

Gave up and just disconnected the battery. It was easier. Didnt make me recalibrate anything.

Sponsored