Hi all I'm new here and am looking for help.

My quick clear screen is not working on either my Ranger or my partners c max, I have owned a c max before where the screen only half defrosted (passenger side) but neither of these are working since we bought them (both used purchases). 

The light on both vehicles lights up but nothing happens I have an obd but I think I need to upgrade this as it doesn't seem to be able to fully scan the vehicle, does anybody have any tips on fault diagnostics for the quick clear screen.

Bin the OBD code reader and use FORScan.

What is the voltage of the battery measured with a multimeter ?

Since you have never seen either screen work you need to start from the beginning and do some basic tests. Have you checked the Fuses? Have the windscreens been replaced at sometime in the past?

Use the multimeter and check for voltage at the screen connection points - Remember the heated front screen will only operate with the engine actually running and the outside temp less than 7^oC (that shouldn't be a problem at the moment).

 

I blame modern cars thinking they are 'smart'! My 1990 RS Turbo had a heated front windscreen which I loved, & in 3 years of ownership, it never failed once. But the car didn't have a host of 'computers' littered in it to screw things up 

Hi guys thanks for the replies and apologies for my late response but at a children's party late yesterday, as the battery started to sound a little weak lately I replaced it on Saturday but still no heated screen also this morning when I arrived to site it still leapt into battery saving mode even though it's a new battery.

 

The heated screen will not work if battery State Of Charge (SOC) is too low and Ford, in their infinite wisdom, do not allow the battery to charge above 80%, in the name of emissions, as there is a very small drag when the alternator is charging the battery. Couple this with the list of things that have to be correct for the power-hungry things to operate, such as Stop/Start and heated front screen, and you may well find that the heated screen does not operate at precisely the time that you need it, when the car and ambient temperature is cold. You can either keep the battery permanently connected to a smart charger when you are not using it or you get Forscan, or find a volunteer with Forscan, to change the SOC target to 90 or 95%. I have changed mine to 90% and the heated screen now works when I ask it to and the Stop/Start now works as intended.

Incidentally, when you replaced the battery did you let the car know that you had changed it? You need to do this or the car will still "think" it's on the original battery.

 

4 hours ago, Paulius55 said:

Incidentally, when you replaced the battery did you let the car know that you had changed it? You need to do this or the car will still "think" it's on the original battery.

 

Hi great reply thanks, no I did not reset as my elm obd does not support all functions and I assumed the removing of the battery would rest it but we all know what            ***** u me does so yes I need to upgrade to a Forscan. 

I am looking but am a little confused as the ones online look like the elm unit I have, can you recommend a link where I can get the correct unit.

 

......and finally (was that the two Ronnie's ?)*

Even though you bought a new battery they are not supplied fully charged. They come with around about a SOC of 70% and the customer is expected to fully charge them before use.

As said above did you do the BMS reset after replacing the battery ? If not it will take 2 or 3 days for the BMS to establish the condition of the new battery.

 

* just remembered it was the end of News at 10 - Trevor McDonald

FORScan (it's free for laptop use): https://forscan.org/download.html

ELM327(modified) cable: https://tunnelrat-electronics.fwscart.com/USB_Modified_with_switch_ELM327/p4541936_17045457.aspx

OR better than the ELM327(modified) use the new vLinker FS

vLinker FS cable: https://www.amazon.co.uk/Vgate-vLinker-Adapter-FORScan-MS-CAN/dp/B0952P4MLP/ref=asc_df_B0952P4MLP/?tag=googshopuk-21&linkCode=df0&hvadid=534732308385&hvpos=&hvnetw=g&hvrand=5541850566415961925&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1006688&hvtargid=pla-1430824679036&psc=1

 

4 hours ago, unofix said:

......and finally (was that the two Ronnie's ?)

Even though you bought a new battery they are not supplied fully charged. They come with around about a SOC of 70% and the customer is expected to fully charge them before use.

As said above did you do the BMS reset after replacing the battery ? If not it will take 2 or 3 days for the BMS to establish the condition of the new battery.

Will attempt the reset tonight and charge the battery to full.

15 hours ago, unofix said:

 

Battery reset however this method did not work for me for some reason but flashing high beam 5 times and pressing brake 3 times did.