Automated transmission maintenance

[EtherealWanderer]

Greetings,
I have just come back from a vacation in France during which I traveled slightly over 4000km in my 2012 Evoque. The automobile functioned flawlessly and provided immense pleasure while driving.
As the holiday drew to a close, I began to perceive a faint and discreet 'knocking' noise emanating from beneath the foot pedals. It persisted for a brief moment as I departed from an intersection and accelerated before coming to a halt. It was never perceptible at highway speeds or during deceleration. I began to contemplate the gearbox solely due to the persistent noise that became apparent as I accelerated through the gears.
Yesterday, I ventured to the stores, and upon restarting the vehicle, an orange warning indicator illuminated on the dashboard indicating a 'gearbox fault.' It remained for under 5 seconds before vanishing. The vehicle commenced operation smoothly, and I navigated home without difficulty. The subtle 'knocking' persisted at reduced speeds, leading me to suspect a potential gearbox problem.
The vehicle has remarkably low mileage (79,000 km) considering its age, and I have never serviced the transmission. My Evoque is the inaugural vehicle with an automatic transmission that I have possessed, thus I feel quite uncertain about them.
Does the gearbox necessitate routine maintenance? I consistently maintain the remainder of the vehicle.
Any guidance and recommendations will be sincerely appreciated. I appreciate your assistance beforehand.

[bentleygt77]

Greetings,
Your transmission requires servicing at 60,000 miles, irrespective of any knocking sounds. I would commence at this point and then have the workshop conduct an investigation while performing the gearbox service. The total expense for the gearbox service amounted to £425, and it is advisable to seek a specialized garage since this is a complex procedure that necessitates oil testing at different temperatures throughout the service.

[bentleygt77]

I can also state that I have experienced analogous gearbox fault indicators, all of which were verified to be due to a malfunctioning auxiliary battery. If your auxiliary battery has not been replaced, it will have exceeded its suggested lifespan of five years. One can effortlessly locate an OEM replacement auxiliary battery on eBay or Amazon; it cost me £14, and the installation by an auto electrician was £20. I advise against using a standard garage, as they will charge over £100.

[bentleygt77]

Additionally, should you opt to service your automobile's gearbox, I would advise that you also service the haldex transmission, which should occur at approximately 40,000 miles. It is the component that propels the four-wheel-drive transmission. Recommendation - purchase the OEM service kit from eBay for £56 and arrange for a technician to service the Haldex concurrently. The technician should require merely an additional hour to service the haldex unit.
Please inspect the driver's side suspension behind the wheel for any damage or a broken spring regarding the knocking.

[bentleygt77]

I must emphasize that my insights stem from personal experience, and I am the proud proprietor of a 2012 automatic 2.2 diesel R Dynamic that operates as if it were new due to the additional maintenance performed, with 114,000 miles on the odometer.
Could you inform me if you receive a notification on your dashboard that appears briefly stating, "low battery, system will shut down in 3 minutes"? Thank you