Locked out - another 12v saga

[rb33gl]

Just had an interesting experience with the 12v battery. On returning home for a 2 week holiday, I found the car wouldn’t unlock. All buttons on the remote created a red signal on the fob – no opening of doors, boot or bonnet.

Changed the fob battery, held the fob at the top right of the rear windscreen, still no joy. Tried the emergency key – no result - I could hear nothing and the door wouldn't open.

So I called Porsche Assist, which in the UK is operated by the AA. They were very good, arriving in 40 minutes (turned out the guy lives 10 minutes away and we were his first job on Monday morning, so he even had time to fill up).

He called up Porsche’s manual on his iPad and found there is a technique with the emergency key the owner’s manual doesn’t tell you about. You have to put the key in and turn it clockwise and hold it in that position for about 5 seconds. The door handle can then be operated manually.

Once inside the car, he connected a 12v supply to the fuse box (which is well documented elsewhere on this forum) to open the bonnet. He then connected a 12v charger to the Lithium battery and after a few minutes the car sprang into to life. The PCM system gave a warning 12v battery low, connect to charger warning, but this disappeared after a few on-off cycles.

It’s clear even a small Lithium battery should last longer than 2 weeks and I wanted to make sure it had plenty of charge, so I call the OPC to find out the best way of doing this. If you don’t have a Lithium battery charger (my CTEK is only for lead batteries) it can only be done by driving it. They said the car’s alternator (??) will do this, but couldn’t say how long it took.

Interestingly, they didn’t seemed concerned about a software update for the battery monitoring system either, saying it might have been caused by “Germany fiddling with some of the Connect settings”.

I drove around and found the state of charge readout in dial 3 read 13.4v initially, and after a few miles was showing 14.5v before falling back to 13.5v. Nothing that would suggest a fault.

Plugging in the charger to the main battery doesn’t do anything either. Once the charge in the 12v has dropped to a low level (what that is, heaven knows) it will cut supply to all the controls to protect itself. Seems bizarre you can be sitting on 93kw and not be able to open the doors...

I don't really trust this battery now but don't really want ot book it in for another 2 days, especially when the OPC say no software change is needed.

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[batteredhaddock]

Yeah its mad these issues even happen. Not seen a lot of posts regarding 12V recently on Taycan (was a big issue at launch) though so shame to hear it has happened to you (I did look for a backup 12V booster suitable for Li-Ion but couldn’t find one, certainly not outside of commercial use). Was there anyone at home with keys when you were away at all by any chance? Just seen a video from one of the Ioniq 5 owners who has had a ton of 12V issues. Seems from his monitoring software the family just walking back and forth near the car was setting off their version of comfort access, each time causing a little hit on the battery (alongside standard drain). Previous behaviour was one 12V charge a day, so it could result in it dropping too low. Now Hyundai seem to have an agressive charge as soon as hits ~12.6V and he has seen multiple top-ups per day since that update.

Think the original Porsche issues seemed linked to constantly polling for smart charging keeping the 12V too active.

 

[XLR82XS]

He called up Porsche’s manual on his iPad and found there is a technique with the emergency key the owner’s manual doesn’t tell you about. You have to put the key in and turn it clockwise and hold it in that position for about 5 seconds. The door handle can then be operated manually.

Sorry to hear - sucks. The key access is stated in the manual, at least the paper version. My 12V died 2 months from new. There was a software update for the 12V issues. Since my car had the update I have had zero 12V issues. (June '21)

 

[rb33gl]

No one at home other than daughters feeding the cat - I made sure the key (only use 1, the spare is in the safe with the battery out) was some way away so it did not keep trying to register with the car. Perhps I need a Farady bag for future holidays

 

[Tooney]

@rb33gl Sorry this happened to you. Thanks for sharing. Emergency unlocking: One more thing for us to know.

In reading the 2022 printed manual, page 48, it seems to indicate that to unlock the door you turn the emergency key counterclockwise (to the first point of resistance, then continue turning as far as it will go, using a certain(?) amount of force). And, clockwise is to lock the door.

Different than turning it clockwise to unlock and holding it for 5 seconds.

Any thoughts?

( at me having to research how to unlock my car door..... )

 

[W1NGE]

Just had an interesting experience with the 12v battery. On returning home for a 2 week holiday, I found the car wouldn’t unlock. All buttons on the remote created a red signal on the fob – no opening of doors, boot or bonnet.

Changed the fob battery, held the fob at the top right of the rear windscreen, still no joy. Tried the emergency key – no result - I could hear nothing and the door wouldn't open.

So I called Porsche Assist, which in the UK is operated by the AA. They were very good, arriving in 40 minutes (turned out the guy lives 10 minutes away and we were his first job on Monday morning, so he even had time to fill up).

He called up Porsche’s manual on his iPad and found there is a technique with the emergency key the owner’s manual doesn’t tell you about. You have to put the key in and turn it clockwise and hold it in that position for about 5 seconds. The door handle can then be operated manually.

Once inside the car, he connected a 12v supply to the fuse box (which is well documented elsewhere on this forum) to open the bonnet. He then connected a 12v charger to the Lithium battery and after a few minutes the car sprang into to life. The PCM system gave a warning 12v battery low, connect to charger warning, but this disappeared after a few on-off cycles.

It’s clear even a small Lithium battery should last longer than 2 weeks and I wanted to make sure it had plenty of charge, so I call the OPC to find out the best way of doing this. If you don’t have a Lithium battery charger (my CTEK is only for lead batteries) it can only be done by driving it. They said the car’s alternator (??) will do this, but couldn’t say how long it took.

Interestingly, they didn’t seemed concerned about a software update for the battery monitoring system either, saying it might have been caused by “Germany fiddling with some of the Connect settings”.

I drove around and found the state of charge readout in dial 3 read 13.4v initially, and after a few miles was showing 14.5v before falling back to 13.5v. Nothing that would suggest a fault.

Plugging in the charger to the main battery doesn’t do anything either. Once the charge in the 12v has dropped to a low level (what that is, heaven knows) it will cut supply to all the controls to protect itself. Seems bizarre you can be sitting on 93kw and not be able to open the doors...

I don't really trust this battery now but don't really want ot book it in for another 2 days, especially when the OPC say no software change is needed.

I know it won't help if I say it shouldn't happen but if a MY21 car have you had all updates and recall campaigns applied - some were specifically for the 12v drain issue (my assumption is 'yes')?

One of the fixes was to detect a voltage drop in the 12v and for the HV battery to top it up even when idle / parked up - odd this did not kick in.

Another was to disable PLC from car (on PMCC web interface) as this could drain the battery whilst the car tried to communicate with a network powerline communication device when connected to the PMCC for a charging session rather than defaulting to WiFi.

Of course it is entirely possible the 12v has a production fault and you were just unlucky.

 

[rb33gl]

I know it won't help if I say it shouldn't happen but if a MY21 car have you had all updates and recall campaigns applied - some were specifically for the 12v drain issue (my assumption is 'yes')?

One of the fixes was to detect a voltage drop in the 12v and for the HV battery to top it up even when idle / parked up - odd this did not kick in.

Another was to disable PLC from car (on PMCC web interface) as this could drain the battery whilst the car tried to communicate with a network powerline communication device when connected to the PMCC for a charging session rather than defaulting to WiFi.

Of course it is entirely possible the 12v has a production fault and you were just unlucky.

Yes it's had all the updates. When I called the OPC to update them this pm, the guy did mention the last update included topping up the 12v using the main battery. He couldn't explain why it didn't happen this time.

I've also just checked the voltage again, without putting it into Drive. It started off reading 11.7v, but quickly rose to 13.5 as I watched it. Curious.

 

[Windpower]

I did look for a backup 12V booster suitable for Li-Ion but couldn’t find one, certainly not outside of commercial use

This is the model I use at home:
https://www.amazon.co.uk/NOCO-GB40-UltraSafe-Lithium-Starter/dp/B015TKUPIC
I think it cost about $100 (US).

 

[batteredhaddock]

This is the model I use at home:
https://www.amazon.co.uk/NOCO-GB40-UltraSafe-Lithium-Starter/dp/B015TKUPIC
I think it cost about $100 (US).

Thanks, can only see support for lead acid on the spec sheet though?

 

[gusone]

Just had an interesting experience with the 12v battery. On returning home for a 2 week holiday, I found the car wouldn’t unlock. All buttons on the remote created a red signal on the fob – no opening of doors, boot or bonnet.

Changed the fob battery, held the fob at the top right of the rear windscreen, still no joy. Tried the emergency key – no result - I could hear nothing and the door wouldn't open.

So I called Porsche Assist, which in the UK is operated by the AA. They were very good, arriving in 40 minutes (turned out the guy lives 10 minutes away and we were his first job on Monday morning, so he even had time to fill up).

He called up Porsche’s manual on his iPad and found there is a technique with the emergency key the owner’s manual doesn’t tell you about. You have to put the key in and turn it clockwise and hold it in that position for about 5 seconds. The door handle can then be operated manually.

Once inside the car, he connected a 12v supply to the fuse box (which is well documented elsewhere on this forum) to open the bonnet. He then connected a 12v charger to the Lithium battery and after a few minutes the car sprang into to life. The PCM system gave a warning 12v battery low, connect to charger warning, but this disappeared after a few on-off cycles.

It’s clear even a small Lithium battery should last longer than 2 weeks and I wanted to make sure it had plenty of charge, so I call the OPC to find out the best way of doing this. If you don’t have a Lithium battery charger (my CTEK is only for lead batteries) it can only be done by driving it. They said the car’s alternator (??) will do this, but couldn’t say how long it took.

Interestingly, they didn’t seemed concerned about a software update for the battery monitoring system either, saying it might have been caused by “Germany fiddling with some of the Connect settings”.

I drove around and found the state of charge readout in dial 3 read 13.4v initially, and after a few miles was showing 14.5v before falling back to 13.5v. Nothing that would suggest a fault.

Plugging in the charger to the main battery doesn’t do anything either. Once the charge in the 12v has dropped to a low level (what that is, heaven knows) it will cut supply to all the controls to protect itself. Seems bizarre you can be sitting on 93kw and not be able to open the doors...

I don't really trust this battery now but don't really want ot book it in for another 2 days, especially when the OPC say no software change is needed.

Did you try the app to unlock? Just asking as isn't mentioned.

 

[simcity]

(I did look for a backup 12V booster suitable for Li-Ion but couldn’t find one, certainly not outside of commercial use).

Not a booster per se, but I’ve found that CtEK’s small Lithium-specific battery charger does a pretty good job of reviving a flagged lithium battery on my bikes. Sometimes needs several goes if the battery is really depleted, but usually successful.

 

[W1NGE]

Did you try the app to unlock? Just asking as isn't mentioned.

Nice idea but still need power in the car and all of it 12v dependent - LTE, PCM, locks etc.

 

[batteredhaddock]

Not a booster per se, but I’ve found that CtEK’s small Lithium-specific battery charger does a pretty good job of reviving a flagged lithium battery on my bikes. Sometimes needs several goes if the battery is really depleted, but usually successful.

Thanks, that could work to have handy at home ? (or I could aim to flag down an EV6 or Ioniq 5 to plug it into if stuck at a. services perhaps ?)?

 

[rb33gl]

Did you try the app to unlock? Just asking as isn't mentioned.

Tried several times - app would just buffer without anything happening on the car

 

[MTGBUK]

Ioniq 5 owners seems to be having the same 12v issues. Nice video where owner has had an update that seems to have fixed the issue and fitted a 12v battery monitor to see what’s happening with the 12v battery. Thankfully 12V issues seem to be less of an issue but something owners who could do if they are still having issues.

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