Content by MickeySw in January, 2026

Standard transponder keys don’t have a battery to boost their signal and need to be in close proximity to the sender/receiver circuit of the car…

It’s a common misconception that driving at motorway speeds will heat the MG5 battery sufficiently to allow decent Rapid charge rates. The system is designed that to keep the cells around 10 deg C or ambient, whichever is higher..

It’s more likely it wasn’t working at all as it’s difficult to get the timing right (some say impossible, if you don’t have an OBD reader to get the to cell/coolant temperatures)?

Have you ever managed to successfully use this feature, I.e. get ‘summer-ish’ charge rates?

Can you elaborate on how to achieve that in freezing temperatures?

I gather it doesn’t work with the car in READY either, then it’s not related to a low aux battery voltage unless your CCU has gone faulty?

Pretty much as expected

Mary was well aware that the car wasn’t locked, but took a chance, did I mention the sales were on? In hindsight, I could have locked it with the app but ‘there was nothing in there to take anyway?’