Low battery causing C Locking self activating?

[tuneyo]

Has anyone come across this symptom? 2016 Polo 1.4 TSI GT. Central locking activates and alarm arms on its own. So intermittent it can do it as soon as unlocking or if car is left unlocked it can do it after several hours sitting on the drive. Doors and tailgate all signal opening as normal on display and driver’s door signals normal ‘door open’ warning. All interior lights function as they should. So, I can unlock car, open drivers’ door and on closing sometimes CL reactivates. Go for a drive, leave car unlocked on drive, car will lock itself after 1,2,3 or 4 hours even longer, sometimes never, until I lock overnight. I realise after 5 ½ years battery is not great, stop/start sometimes does not work, I assume this is due to battery age but car starts ok with no usual aging battery symptoms. ‘Standing’ battery voltage is around 12.8-12.2 volts occasional down to 11.99. The question I have is it possible the battery condition is causing this random issue? Thanks.

[Crasher]

Have the car scanned first.

[tuneyo]

Sorry forgot to mention, no error codes on scan...

[Crasher]

Using which system?

[tuneyo]

Vcds

[tuneyo]

Sorry, not Vcds but VAS 6160c. Got confused!

[Crasher]

Start with a new battery then, modern cars are very sensitive to a weak battery and can do all sorts of odd things. We had a Polo 6C in a few weeks back that was going loopy and it was just a weak, original, battery. We only fit Varta like for like AGM, avoid Yuasa like the plague.

[tuneyo]

Thanks, I will put car on tickle charge over weekend to see if problem shows up with a little more voltage in battery as I would like to prove the issue first before investing in new one. Although with the age of it and the stop/start not always working it is probably only postponing the inevitable. It would be annoying though if a new battery did not make any difference. It used to be the case as the first signs that the battery's time was up was a sluggish starter in the morning, times have changed!

[tuneyo]

Just an update. Had the vehicle on a solar panel trickle charger for 4 days, apart from 4 brief journeys out. Left unlocked during daylight hours and the car did not lock itself. The solar panel just maintains a voltage between 12.4-12.8 volts depending on the weather conditions. On removing this charger and taking a short journey of 3 miles and with the stop/start showing disabled the car started locking itself again even with a voltage reading of 12.5volts. The solar charger must be 'smoothing' out the voltage and cancelling out any 'spikes' causing this self locking symptom. That's my theory anyway! Starting from cold is still no problem at all. At my last service 1 month ago the battery health was good but needs recharge (which was done). So new battery on order, plus reprogramming of course. I hate some new technology! Hope this my help someone else that has similar.