Hi

As a new owner of a Ford SMAX 2019, I'm suffering a couple issues (Heated Windscreen and Auto Start-Stop not working). I've researched as much as I can and it seems the issue may be related to a Battery Target State of Charge being less than the minimum required. This tallies with extra large journeys - occasionally the auto start-stop will work. Due to weather conditions I haven't had the opportunity to prove the windscreen in the same way.

I have had the battery checked.  It is in good health. 

Assuming this is a Battery Target State of Change issue, I'm trying to find out how to change it.  Forscan have stopped selling software, I dont know of any locals in my area (Leamington Spa/Warwick) and the dealer wants to run a default diagnostics check (£100's before we get going in the right direction I assume).

Would really appreciate a steer on forscan contacts, or affordable alternatives I could use as a first timer (do all ODB readers have this capability?), or counter views if you think it is a different issue. 

Thanks very much!

Yes it is probable that your battery State Of Charge (SOC) is low, even if the battery health is good. You need to forget all about Stop/Start not working, there are approximately 112 reasons why it doesn't work when you think it should. There are well over 250 individual threads here on the forum with "my Stop/Start isn't working".

The heated front screens won't work as you say if the battery SOC is low. They also won't work if the ambient temperature is above 7^oC

You can still download FORScan (free) for a windows laptop. You can then get the free 2 month trial licence which will allow you to make programming changes. I'm not fully sure that the SOC is adjustable on a S-Max, but it might be. If so then it needs adjusted from the factory default of 80% up to a more reliable 95%

Unfortunately, adjusting the SOC will most probably not offer a permanent solution at this time of year, and like many others here on the forum, you will still need to charge the battery for 12 hours every 4 to 5 weeks.

FORScan:

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

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:   FORScan123

 

Thanks so much. 

I'll post back an update.

It worked!  

Using Forscan I adjusted the Target State of Charge to 95% and charged the battery. Frost over the last couple of mornings has been tackled by a functioning heated windscreen - at last!

Hope this helps others. 

 

On 2/6/2025 at 8:54 AM, User2000 said:

It worked!  

Using Forscan I adjusted the Target State of Charge to 95% and charged the battery. Frost over the last couple of mornings has been tackled by a functioning heated windscreen - at last!

Hope this helps others. 

An easy way to monitor your SOC in real time is to buy an OBDLink MX or similar that plugs directly into you OBD port. Download the Car Scanner Pro app (or use OBDLinks own, other apps are available) and set it up with the modules and values you wish to monitor.

I use an old mobile handset mounted in a phone holder to monitor DPF soot content, exhaust 1 &2 temps, oil and coolant actual temps, battery SOC and live alternator Voltage output! 

I had 6 years of no Stop Start (wasn't bothered about this as I disable it anyway) or heated windscreen (very bothered about!). Ford spend 3 years of warranty trying to find a fault, nothing was wrong apparently.

With this reader, I figured out the BCM monitoring sensor on the battery was faulty as Battery SOC would be 30% one day, 58% the following morning, 2% the next day and the car behaved as per the table, disabling functions as a precaution.

£125 later, I changed the sensor myself (easy to do) and now my cars SOC remains accurate.