[GV_FocusST3]

I have two issues - hopefully completely unlinked but both appear occasionally when I get in my car. Can be when I had a short journey or before the drive home after work.

Issue 1 - happily drive along with climate control at 19C with vents on at windscreen and head direction. When I get back in the car and start the engine, the air-con has selected AUTO, A/C ON and 22C. WTF?

Issue 2 - listening to DAB radio, on one of my programmed stations. When I get back in the car and start the engine, now selected to random FM station. Again, WTF?

 

[Radiator]

Does anyone else use the car?

 

[alexp999]

How is your battery? Those both sound like things that happen when the battery isn't able to supply enough power or is disconnected. I wonder if when you crank the engine it's sometimes pulling so much the voltage drops and the modules reset.

 

[lc69]

I have two issues - hopefully completely unlinked but both appear occasionally when I get in my car. Can be when I had a short journey or before the drive home after work.

Issue 1 - happily drive along with climate control at 19C with vents on at windscreen and head direction. When I get back in the car and start the engine, the air-con has selected AUTO, A/C ON and 22C. WTF?

Issue 2 - listening to DAB radio, on one of my programmed stations. When I get back in the car and start the engine, now selected to random FM station. Again, WTF?

I'm glad you've posted this question, as I too on occasions experience exactly the same symptoms and have wondered why. I fitted a new Bosch battery April 2021 so I don't think it's that.

 

[K3FUS]

My Fiesta ST kept doing this, turned out to be the battery to body earth wire, it was lose at the body end.

 

[sttwoton]

Check the mega fuses for cracks, sometimes they can have cracks you can barely see, check the small white wire that connects to the positive battery connection , they can corrode and is part of the battery monitoring system, the fuses are located on the front of the battery box.

 

[GV_FocusST3]

Just me using the car. Battery is fine. @sttwoton will check for cracks - thanks

 

[sttwoton]

What happens is, the fuses can crack, but be so small that you can’t see it, it may check out ok with a multi meter, but with vibration, you get poor connection.