App frozen / UK

[JasMK]

All I need to do know is find the fuse box ?

It's in the drivers side footwell. The panel that your right foot rubs on, remove that to find the fuses, it just prizes off easily.

Then to remove the pink fuse retaining clip you have to find the lug that locks it in place - it's on the far side and you need to push it away from you to release the clip, a little fiddly for sure. Theres a diagram inside the panel or refer to the manual (on the app) to locate the fuses correctly.

Then just pull both fuses, wait a few mins then put them back (in the right place!) and re-assemble. 10 min job, and 30 mins with the chiropractor after...

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[BigBob]

It's in the drivers side footwell. The panel that your right foot rubs on, remove that to find the fuses, it just prizes off easily.

Then to remove the pink fuse retaining clip you have to find the lug that locks it in place - it's on the far side and you need to push it away from you to release the clip, a little fiddly for sure. Theres a diagram inside the panel or refer to the manual (on the app) to locate the fuses correctly.

Then just pull both fuses, wait a few mins then put them back (in the right place!) and re-assemble. 10 min job, and 30 mins with the chiropractor after...

Great, thank you. Sounds like a good workout so see if my shoulders still dislocate really easily!

I will give it a go this morning. If the next thing you receive from me is a string of expletives, you’ll know I’m in an ambulance on laughing gas for a popped shoulder, or I’ve (you’ve) bricked my car!

 

[whitex]

@whitex Thank you for the diagram of "connect function" distribution. Several owners have mentioned dealers replacing OTA control unit to fix datacomm/no LTE problems.

I'm trying to get a better understanding of the components and functions of Taycan's datacomm system.

Forum posts - some by you - have shown photos of OTA control unit.
Is OTA control unit a separate hardware item, or is it a part of the ConBox-High unit?
What function(s) does OTA control unit perform?

First, I must say that my information comes from internet research, talking to techs, and some hands on reverse engineering, though that hands on part was on salvage parts I got from ebay, as my car was 20 months delayed. I was getting stuck on things which I could lookup in a real car, such as exactly what is connected to what pins (I had to guess based on circuit board design/layout and information I dug out) or for example what message lets the PCM know there is a key in the car so it turns on beyond showing the "off" screen. By the time I got my car, I had other things happening in my life which means I never got back to it, and not sure if/when I will - I might do some partial reverse engineering to integrate my custom radar/lidar solution which has been on a back burner for too long now. Also, my reverse engineering setup is pre-uPdate.

That disclaimer out of the way, the OTA module is a separate ECU from the ConBoxHigh. As far as I could figure out, the OTA module is responsible for the application of firmware OTA's, as it has a few different automotive buses connected to it (again, no car so I never nailed down exactly which one went to which ECU, but I'm fairly sure they were there to perform firmware updates), an automotive microcontroller (from Renesas) and a full fledged, dual ARM Cortex-A9 application processor SoC from NXP with bunch of eMMC storage. I suspect, but have not confirmed, that the PMC actually gets the updates and sends them to the OTA module for application. Lastly, the OTA ECU I picked up had a bunch of automotive bus transceivers (like CAN or Ethernet) not populated on the PCB, so perhaps it was supposed to do a lot more initially but got neutered in some later iteration, or it's a stock part from one of the Tier 1 suppliers and they just don't populate what the customer is not using.

The ConBox High is pretty much a wireless connectivity provider, LTE, WiFi, GPS, BT. It also handles SoS calls (has access to microphone and the SOS red/green LEDs are directly controlled by the ConBoxHigh). It has its own battery which ensures at least some it is powered 24/7. I asked a Porsche tech and he confirmed that his battery is something they replace on Porsches (not just Taycan) every so many years (sorry, forgot the actual number).

@whitex
The diagram you posted shows 10 antenna symbols. Does this mean the ConBox-High is connected to 10 antennas?

I found 8 - 4 LTE antennas, 3 Wifi/BT antennas (it's a quad connector, but one is unused), 1 GPS/GNSS.

@whitex
When LTE is shown as not available in PCM and we rule out poor local cellular service and Porsche back-end application service faults as causes, what in the car is possibly causing the outage, which often seems to be intermittent/resolves on its own in a couple of days?

There were a couple of posts in the past that criticized the Conbox-High as a relatively low-quality telematics device. Is that a root cause of no LTE issues?

Missing connectivity on the PCM is unlikely to have anything to do with the OTA module. It's either the ConBoxHigh or the Gateway (another ECU which essentially is a giant bridge between Ethernet, CAN, FlexRay buses). My money is on the ConBoxHigh since if the gateway was bad, other functions would die too, so it would have to be only the Ethernet bridge that malfunctions in it. Oh, all Ethernet is Automotive 2 wire BroadReach, in case you were tempted to tap into them (you'll need an adapter which is not cheap).

Also, I am not sure what happens if the ConBoxHigh battery fails, perhaps that is what can cause connectivity issues for a while until the system reboots itself and somehow reinitializes? Or, maybe the ConBoxHigh has a software issue which is solved with a reboot, but with battery backup the reboot doesn't happen every time the car powers down, only every few days or by some watchdog once it hangs completely. Perhaps when the battery is dead, pulling the fuses will drain whatever is left in it quick and cause a true power cycle where everything is initialized from scratch (longer process so they avoid doing that every time the car powers on)? All these are just my speculations, based on what I have learned about the Taycan so far.

 

[BigBob]

Yeah, I had the same problem for a few days after being away for a week. I ended up pulling the fuses that power the Wireless Data Control Unit (Row B 1 & 10) and after 5 min the LTE symbol was back. Also lost internet radio but had the SOS LED green.

App connecting fine since, so worth a try before booking into the dealer?

Ok, half-wit alert time!

I don't seem to have a fuse in B1, or do the numbers go from right to left (although i note it has 1-12 imprinted above)?

Also my manual says the data control unit are in B10 and B2, and that B1 is the Gateway control unit (whatever that is!)

 

[Tooney]

@whitex Thanks for your comments and info about the Porsche connect hardware.

Since several owners have reported having the OTA box replaced to cure datacomm outages, I wonder about the role of the OTA box for Porsche connect services. Maybe for establishing/repairing/resetting user or eSim registration and access? It is definitely involved per TSB linked below.

https://static.nhtsa.gov/odi/tsbs/2021/MC-10204102-0001.pdf

My other cars are much older and have minimal need for external communications. Is the apparent complexity of maintaining and diagnosing datacomm for the Taycan typical of other current vehicles? Seems a mess to have to take your car into dealer to figure out why it isn't communicating.

 

[whitex]

@whitex Thanks for your comments and info about the Porsche connect hardware.

Since several owners have reported having the OTA box replaced to cure datacomm outages, I wonder about the role of the OTA box for Porsche connect services. Maybe for establishing/repairing/resetting user or eSim registration and access? It is definitely involved per TSB linked below.

https://static.nhtsa.gov/odi/tsbs/2021/MC-10204102-0001.pdf

OTA-FC module in that TSB is simply one of the clients of the LTE connectivity for which the TSB says to ensure connectivity. PCM(MIB) is another such clients. PCM and OTA get their connectivity from the Gateway which gets it from the ConBoxHigh. It is possible that when OTA module fails, PCM can detect that status and report it as lack of complete connectivity to the user, even if PCM has connectivity of its own - OTA is part of Porsche Connect service, so perhaps all of its components need to be connected for PCM to give it a "green light".

My other cars are much older and have minimal need for external communications. Is the apparent complexity of maintaining and diagnosing datacomm for the Taycan typical of other current vehicles? Seems a mess to have to take your car into dealer to figure out why it isn't communicating.

Yea, cars are getting quite complex nowadays. With the complexity, diagnosing becomes more complicated, hence not exposed to the end user, as there wouldn't be much the end-user could do. I suspect Porsche essentially has one indicator for connectivity which is showing car connected only when everything (so primarily PCM and OTA) is connected and reporting. When that fails, it takes a service tech to figure out the reason. For example if PCM has internet but OTA does not, that is different than if neither PCM nor OTA have it, but to the end user it doesn't matter much, in both cases the car's complete connectivity is not working, so it needs service. Giving end users diagnostic information for things which they cannot service themselves anyways tends to generate more confusion than it helps, for most people. General rule of thumb is only provide the end user with information they can act on - simplifies support, implementation and even maintenance (if things change, you don't have to notify hundreds of thousands of end users, only a few hundred techs).

 

[BigBob]

Ok, half-wit alert time!

I don't seem to have a fuse in B1, or do the numbers go from right to left (although i note it has 1-12 imprinted above)?

Also my manual says the data control unit are in B10 and B2, and that B1 is the Gateway control unit (whatever that is!)

In the end, I pulled the 3rd from right (10 I think) for 5 minutes. Just long enough to get a long screwdriver with some chewing gum stuck to it, to retrieve the fuse that dropped into a recess behind some metal framework thingy.

anyway, no change yesterday, though it has mystically started working overnight.
?‍

thanks all for help and suggestions.

 

[JasMK]

In the end, I pulled the 3rd from right (10 I think) for 5 minutes. Just long enough to get a long screwdriver with some chewing gum stuck to it, to retrieve the fuse that dropped into a recess behind some metal framework thingy.

anyway, no change yesterday, though it has mystically started working overnight.
?‍

thanks all for help and suggestions.

Hi Bob,

Sorry for not helping out with the question. If you looked at the diagram on the reverse of the footwell panel it would show that fuse number 1 is on the right side, so it would have been the 2nd from the right end and the last one on the left.

However any use of chewing gum will normally provide miraculous results... glad it's working now.

 

[BigBob]

Hi Bob,

Sorry for not helping out with the question. If you looked at the diagram on the reverse of the footwell panel it would show that fuse number 1 is on the right side, so it would have been the 2nd from the right end and the last one on the left.

However any use of chewing gum will normally provide miraculous results... glad it's working now.

No diagram on the reverse of my panel. Also missing the tool to get the fuses out, hence my sausage finger failure and chewing gum requirement!

But thank you!

 

[Leccy61]

Tried to be systematic in going through the steps in the excellent @Tooney post on the first page of this thread for the lost LTE connection from the car and was about to move on from 2 finger salutes and fuse pulling to 12v battery disconnection.

I had also tried privacy mode activation/deactivation, but saw a post where the advise from smartmobility was to leave privacy mode on for 30 minutes before toggling it off, so did that. The LTE symbol appeared instantly, services resumed and the app is getting updated and sending instructions to the car as it should.

Maybe the problem will come back and it will need a Combox reset or replacement, but thought I’d add this finding to the mix.

 

[Tooney]

I had also tried privacy mode activation/deactivation, but saw a post where the advise from smartmobility was to leave privacy mode on for 30 minutes before toggling it off, so did that. The LTE symbol appeared instantly, services resumed and the app is getting updated and sending instructions to the car as it should.

Thanks for the tip to restore LTE datacomm by activating privacy mode for 30 minutes, then deactivating it.
First time I have read about that method. Certainly easy one to try.

 

[Leccy61]

Don’t understand why it would affect the connection @Tooney it’s not as logical as rebooting the PCM, pulling specific fuses or disconnecting 12v battery, but I’ll take it especially as my Porsche centre aren’t acting quickly.

 

[whitex]

Don’t understand why it would affect the connection @Tooney it’s not as logical as rebooting the PCM, pulling specific fuses or disconnecting 12v battery, but I’ll take it especially as my Porsche centre aren’t acting quickly.

It's a common technique to mitigate common software flaws - change a setting, then change it back. What this does inside software is it sends the new value of the setting to all components that need it, fixing any potential incoherence where some components may think the setting value is X and others think the setting is Y - it forces synchronization, all components "getting on the same page". It's not quiet the iconic "turn it off and turn it back on again" software remedy, but it's a close second.

 

[Tooney]

Don’t understand why it would affect the connection @Tooney it’s not as logical as rebooting the PCM, pulling specific fuses or disconnecting 12v battery, but I’ll take it especially as my Porsche centre aren’t acting quickly.

I added the activate/deactivate privacy mode item to the list of tips for fixing no remote access/no LTE symbol.

 

[Taycan4S_UK]

When my smart lift stopped working in certain locations, I did the PCM restart.... it didn't fix it.
I logged out of Porsche ID and then logged in again... problem solved.

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