According to a media report, the first examples of the Ford Mustang Mach-E in the USA apparently have a software problem that prevents them from driving off, even if the battery is full. The crux of the matter is how the 12-volt system is charged.
The US portal “The Verge” reported on the problems. The 12-volt battery is also an important component in electric cars: its electricity feeds all the control units and systems in the car, and the high-voltage contractors are also opened or closed via the 12-volt network. For example, when the large traction battery is parked, the fuse is “pulled” so that no component of the drive system is live. The 12-volt battery is charged via a DC-DC converter from the traction battery (in the Mustang Mach-E with 400 volts).
But: If the Mustang Mach-E is connected to a charging station, only the traction battery is apparently charged, but not the starter battery. This is only charged via the DC-DC converter while driving, not from the network.
In some adverse circumstances, this can arguably become a problem. For example, if the E-SUV is connected to the charging station overnight, the starter battery will not be charged. But if other consumers on board continue to draw electricity and low temperatures put additional strain on the 12-volt battery, the charge level can drop so far that the car can no longer be started – there is then too little electricity in the battery to power the HV Close contactor again. According to the FordPass app, the vehicles are then in a “deep sleep”.
According to Ford, this only applies to vehicles built before February 3, 2021. An over-the-air update is expected to follow later in the year. Anyone who is already affected should go to the workshop: Ford apparently also wants to check the condition of the 12-volt battery and replace it if necessary. Charging the starter battery yourself is not that easy: it is installed behind the Frunk – but the front hood is unlocked by the 12-volt system and would have to be unlocked manually in further steps.
