Hi. I've had my ST3 2017 for a couple of years now and love it. A few weeks ago I got a message saying "driver assist malfunction", since then lane assistance and speed signs don't work. Also my sunroof and rear wiper have also stopped working. I'm not very technically minded so any help would be most appreciated.

Thank you.

It might be a good idea to clean the windscreen and check the tyre pressures. I doubt if this has anything to do with the rear wiper and the sunroof which should be on different circuits. Check the fuses for those first.

It sounds like a battery issue to me...is it the original battery ??

If so, I would get it tested.

24 minutes ago, anon said:

It might be a good idea to clean the windscreen and check the tyre pressures. I doubt if this has anything to do with the rear wiper and the sunroof which should be on different circuits. Check the fuses for those first.

I did the tyre pressures all round and have cleaned the windscreen. I was told there is another sensor somewhere in the front behind the bumper, is that right?

Appreciate the comment and help, thank you.

23 minutes ago, Phil3747 said:

It sounds like a battery issue to me...is it the original battery ??

If so, I would get it tested.

Thank you.

I had a brand new battery installed last November but I will get it checked as it's still under warranty.

There may be another sensor in the front bumper if you have adaptive cruise control.In that case, see if the cruise control is working. Was the battery fixed at a Ford dealer? Does the stop/start work? If not, there is a procedure to follow which may not have been done by the supplier. Come back to us with answers, please and we can try to assist further.

Windscreen camera, sunroof and rear wiper all have wiring in the roof.  I suspect the loom is wet or damaged somewhere up there.

7 minutes ago, anon said:

There may be another sensor in the front bumper if you have adaptive cruise control.In that case, see if the cruise control is working. Was the battery fixed at a Ford dealer? Does the stop/start work? If not, there is a procedure to follow which may not have been done by the supplier. Come back to us with answers, please and we can try to assist further.

I don't think I have adaptive cruise control. I used cruise control yesterday and it works. I don't use start/stop as I always switch it off. The battery I have is a Yuasa HSB010 Silver 12V, it wasn't fitted by a Ford dealership.

What Tomsfocus writes makes sense. Did everything happen at once? 

One the sunroof was wirking the following day it didn't. Didnt use the wiper till Saturday morning when it was raining before that i have no idea as it is has been sunny.

The Yuasa HSB010 Silver battery fitted is the wrong one, it is not for a Start/Stop car. The Focus ST250 has Start/Stop fitted.

Get the correct battery fitted, carry out a reset of the Battery Management System (BMS) and see how things go.

38 minutes ago, YOG said:

The Yuasa HSB010 Silver battery fitted is the wrong one, it is not for a Start/Stop car. The Focus ST250 has Start/Stop fitted.

Get the correct battery fitted, carry out a reset of the Battery Management System (BMS) and see how things go.

When I put my car registration in when looking for a battery that is one of them that was recommended.

As you keep the stop start turned off, it won't do any harm. I expect that you fitted it yourself. Look up BMS reset and follow the procedure for your car. It is unlikely to resolve the problem but it needs to be done in order to put the car back into the correct condition to allow a proper diagnosis to take place.

25 minutes ago, anon said:

As you keep the stop start turned off, it won't do any harm. I expect that you fitted it yourself. Look up BMS reset and follow the procedure for your car. It is unlikely to resolve the problem but it needs to be done in order to put the car back into the correct condition to allow a proper diagnosis to take place.

I didn't put the battery in. I ordered it and had it installed from Halfords last year. The problems I'm having with the car only started last week.

I've added photos, along with that sunroof and rear wiper not working. 

Good old Halfrauds...I wouldn't trust them to clean my windscreen 😬

Looks like one of the cameras is up the creek. You need Forscan.

On 7/20/2025 at 3:32 PM, AmmerAslam said:

I've added photos, along with that sunroof and rear wiper not working. 

You either have two unrelated groups of faults going on at the same time, which is possible or your BCM is having a bad day and needs reset.

Start by using FORScan and see what Ford specific DTC's are present.

On 4/7/2024 at 8:59 PM, unofix said:

FORScan (for use with Windows Laptop) : https://forscan.org/download.html

It's what many Ford owners use including some Ford technicians.

• vLinker FS, cable for laptop: https://www.amazon.co.uk/Vgate-vLinker-Adapter-FORScan-MS-CAN/dp/B0952P4MLP

OR

• OBDLINK EX, cable for laptop: https://www.amazon.co.uk/OBDLINK-EX-FORScan-OBD-Adapter/dp/B081VQVD3F/ref=sr_1_5

For diagnostic use only:

• vLinker FD, for android phone: https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H82WC8L
• vLinker FD+, for iPhone: https://www.amazon.co.uk/Vgate-Bluetooth-vLinker-Scanner-Diagnostic/dp/B08H8JHWP2

 

Search Tag:   FORScan321

 

On 7/22/2025 at 4:49 PM, Phil3747 said:

Good old Halfrauds...I wouldn't trust them to clean my windscreen 😬

I had no choice at the time. They were the only ones that could come out at short notice and I needed to get to work.

20 hours ago, unofix said:

You either have two unrelated groups of faults going on at the same time, which is possible or your BCM is having a bad day and needs reset.

Start by using FORScan and see what Ford specific DTC's are present.

 

I've ordered a new ODB as the one I had from 5 years ago and forscan didn't like it. Got that when I had my Mondeo and it worked fine on that.

Forscan gives a warning message with old ELM based cables but it does still work correctly for reading data, including DTC's from the car. I wouldn't want to do any heavy reprogramming with it but using it to read DTCs is likely to be fine. 

13 hours ago, pcaouolte said:

Forscan gives a warning message with old ELM based cables but it does still work correctly for reading data, including DTC's from the car. I wouldn't want to do any heavy reprogramming with it but using it to read DTCs is likely to be fine. 

 

Oh well. Worth a try.