Intermittent complete brake failure.

[Hellikopta]

Every 6 weeks to 2 months I seem to randomly get in my car and when I turn it on I get a series of warning messages pop up on the dash.  In order these are:  1. Check brake system 2. ESC service required 3. Hill start assist not available 4. Auto hold system malfunction 5. Pre-Collision Assist not available and then it cycles through them all again.  In the meantime the brake pedal is really stiff and difficult to press down.  If you drive the car in this state it will be fine but the brake is almost non existent in that the car coasts for a while before coming to an abrupt stop. I shouldn't drive it therefore as its not safe.

The last time this happened it started at 5pm and was still faulty at 9.50pm.  In the morning it was right as rain once more.  So the previous time (6 weeks ago) I took it to the dealers but by the time the mechanics got round to looking at it (2 days later) nothing was wrong!

Has anyone experienced this and have any idea on how I can correct it?  

[unofix]

All of the above problems are typically caused by the State Of Charge (SOC) of the car battery being very low. Your car will only ever charge the battery to 80% of it's capacity and once the SOC falls below 70% then all sorts of problems start to occur.

Using a smart battery charger (any make will do), Charge the battery while it is still connected to the vehicle for 12 hours. Make sure that the positive lead goes directly on to the battery terminal, but the negative charger lead needs to be connected to a chassis earth point (Not the battery negative).

After a good charge, I expect you will find all will be sorted. Unfortunately you will need to do the battery charge every 6 weeks or so, it's just the way new cars are, caused by manufactures trying to meet emissions targets.

[Hellikopta]

Thanks Unofix.  Will get a smart battery charger ordered and see how I get on.  The starter battery was only replaced about 2 months ago following a Ford Kuga Phev recall and as I'm using the car infrequently at the moment I'm not sure why it's depleted so quickly?