Hi everyone.

I have a 2016 Fiesta (ecoboost 100ps) and I'm hoping that someone here may be able to help identify the cause of several failures in my car. The first sign of anything wrong was that the front airbag warning light came on, and remained on solidly while driving, and when starting the car I got a pop up on the display saying "Hill start assist not available." I thought that this was strange, but I read on here that the airbag warning light is most of the time a really easy fix by just reconnecting the sensor under the seat. As a result of the lockdown I haven't used the car much over the last 4 months or so, so I havent paid too much attention to it. Today, I needed to drive, and on starting the car I noticed that the buttons to open the windows no longer work, in addition to the two problems mentioned above, but I didn't think anything of it and left. About half way there, it seems that all of the power cut out. All of the dials on the dash, the stereo, and the power steering all shut off (power steering turning off while driving is an awful experience!). Shortly after this the engine cut out and the car wouldn't start up again.

After leaving the car off for around 15 minutes, it started again and I was able to make it almost home before the same thing happened again. I'm most likely going to make a call to the AA shortly to have them take a look at it, but I wondered if someone else here may be able to give me an idea of what is causing this. I do wonder if not using it very much over the last 4 months has messed up the battery. I also took it for a service and MOT around a month ago (which it passed) and I'm wondering if the garage might have messed up my car?

Any help is greatly appreciated!

Many thanks,

John.

Have you checked the cables to the battery terminals? Just in case there is excessive corrosion or if they are loose?

I did take a look, and I think it's ok. I'll take another look while I'm waiting for the AA

Try this to relearn the battery

Ignition on for 10 secs, press rear foglight switch 5 times, press hazzard switch 3 times, wait 10 secs. Battery light flashes. Ign off

If the battery relearn does not fix it it must be the battery. With so many problems occuring the after several months from using the car. Even if the aa say it  checks out ok, I would replace it with the best type your car can take. If you have a efb you could fit an agm type, which is more expensive but might solve the problems. Also remove any paint under the battery earth terminal the bolts to car body. A good earth to the car body is important.

This type of problem has put me off wanting to buy a new Ford. The electronics seem too sensitive to battery voltage or are affected by noise. Or the modules are earthed at separate points and this might cause problems when the voltage changes. It might be the programming in the modules needs fixing to stop these problems.