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Turbo S Cab battery issue?


New member
Hi all, only had the car a week and have a potentially concerning issue with the battery. I bought a lithium Ctek to keep things in check as it will be used quite sparingly. Yesterday I took the car off charge (showing all 7 lights on the Ctek), drove for an hour to my destination, parked for 10 minutes, then an hour back. Mostly motorway cruising with only a few short blasts. When I returned and switched off, I got a message suggesting that the PCM could be used again once the battery level was sufficient (or words to that effect).
Is this a common thing, or have I discovered the beginning of an issue?
I'm off to the Alps in 4 weeks so if a trip to a PC is required I'd rather know ahead of time.
If you're sat with the ignition in aux (engine not running) they usually say something like that, or operation is limited and will shut down to conserve battery

Not a common issue certainly, but a little more information is required to form an opinion.
If you are able to replicate the error and report back with the exact message or maybe take a photo, it might be possible to work through any potential defect.
Could it have something to do with the open top, do you think?

I didn't catch the message for long, it appeared as I was switching the car off. I've discovered that the exact message is 'The PCM can only be used when the battery charge is sufficient' which could be a generic message meaning 'don't run it down' but I do question why it's showing after a decent length of drive.
The Ctek is connected to the +ve battery post and the -ve jump post in front of the wiper mechanism, not directly across both battery posts.
I haven't used the car since so can't tell if it'll do it again, but it is sitting pretty, attached to the Ctek which is currently showing a full 7 green LEDs.
The reason I asked about the connection is I made the error over winter and it caused unpredictable starting battery issues and eventual replacement. The CTEK had all the right lights on.
The reason I asked about the connection is I made the error over winter and it caused unpredictable starting battery issues and eventual replacement. The CTEK had all the right lights on.
Showing 7 green lights indicates the connections are fine.

What you've described is the message that appears in current models each time the vehicle is powered off, but the driver's door is not immediately opened. It's a battery protection measure and indicates the PCM will shutdown after a fixed time in order to save the battery.
Suggest you make a few trips out before your Alpine tour in order to really get to to know your car and verify all is well with the systems.
Take care in the mountains - that car is prodigiously quick! 🥶


I connect my CTEK to the +ve and -ve posts in front of the wiper scuttle panel (engine bay) on the Macan

All CTEK lights go through their usual charging routine and my car always starts no issues.

I am in the process of attaching a quick connect cable directly to the battery terminals in the boot though and running the 2.5m extension out of the boot with a soft cloth under the cable if/where it touches the paintwork.
Did you connect the CTEK directly to the battery posts?
Fair comment, I used a new battery tester the other day and the reading from the +ve and -ve posts in the engine bay compared to connecting directly to the battery terminals was completely different!

To battery, said good battery, healthy etc.
To connecting posts in engine health was 5% - replace battery!!
I have connected directly to the battery posts for the past 10 years on my 2010 987 without issue. Not so on the 718 as described above.
I have connected directly to the battery posts for the past 10 years on my 2010 987 without issue. Not so on the 718 as described above.

I’ve always done the same with my 987.2 Cayman but from the 9X1-series cars I think you’ll find that because they have a battery condition module [which the 987 does not] the recommendation is to connect to the earthing post, presumably to keep the module in the loop. Also it’s recommended that the system is reset when a new battery is installed to optimise the battery charging regime.

Battery post connections have been discussed previously but not really tied down. I have always connected direct to either -/+ve terminals directly. Not body earth as too much opportunity for ‘bad earth’ connection. Any monitoring systems are of course monitoring power coming away from battery (dash display). The main reason for avoiding utilising battery earth direct is because this is where you can generate sparks….potentially battery gases could be ignited as a result.

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