battery light on but charging

[shady]

Hi Im new to the forum and in need of some advice.
Ive got a 59 reg fiesta 1.6 tdci econetic which seems to have a few electrical problems.
Firstl the battery warning light is now staying on constantly.I checked the battery voltage and its arround 12.5 volts and when car is started voltage increases to arround 14v so it would appear charging system is working.I have read up a bit and it seems it could be something to do with a smart charge system.
Any info or advice would be great or ideas how to test the wireing or smart charge system.(which is the smart charge plug on alternator and where is the ecu and does anyone have a wireing /pinout diagram so i can check continuity of wireing loom)?
its been like this over a week now and since this has happened the front and rear heated screens have stopped working and the reverse lights have failed.
Thanks in advance.Shaun

[Tiles80]

Hi
I have a 60 plate fiesta the same model. Having the same issue, did you find a solution?

[shady]

Hi mate.sorry havent found an answer for the problem.lights been on for nearly 12 months now and car still starts every fay.only other info i have is i think mine has a normal lead acid battery on and not a silver calcium type.not sure if this could make a difference.
On mine the reversing lights seem to have packed up with no live going to reverse switch on box and the heated front and back screens stop working as soon as battery light comes on.light normally comes on after about 5-10 seconds after start up or when revved up.
Please post again if you get any further with yours.i tried changing alternator but no change.cheers shaun

[Tiles80]

Ye same with mine, been on for a year, rear demister doesn't work since light came on, looked into it as you've said, not sure what battery I have but on diagnostics got a few issues, have read that you can get a new harness for smart charge. Will keep looking into it. Cheers

[shady]

Mine doesnt come up with any codes on code reader.im thinking its a ecu problem which will be expensive.light can stay on until bulb bloes or i trade it in for me unless someone comes up with a cheap fix.if you get anywhere please keep us updated.
Other problem i had was when we had heavy rain,car cut out and immobilised itself.inside fuse box was really dirty and had blown a fuse.replaced that and dash was like a christmas tree with warning lights.cleared codes and all was fine after.battery lighproblem happened before this and continued after.
Thaught someone on here might of had some ideas but no joy.tried a couple of other forums too but no joy.
Really dont want to go to an auto electrician or ford dealer as they know how to charge.

[Tiles80]

The latest on my car, car struggled to start then kept cutting out, phoned aa who said it was alternator, paid £330 with a local auto electrician, my car had a one cable alternator that was unusual as most are 3 cable/wire. Drove home fine. Following day struggled to start then engine malfunction light came on and car cut out again then wouldn't start. That evening after struggling for a while car started and drove fine. Back to auto electrician to diagnose again but the battery light is still on. It's either that one wire is cut or possibly problem within Ecu. No one seems to know or want to help. Back to garage to check fuel filter is fitted correctly as been told it seems like fuel issue why it's cutting out.

[shady]

Hi.Theres no change with mine,still got light on still charging and running fine.
It appears ford changed from the 3 wire to 1 wire smart charge systems on newer cars.I think the single wire just goes to the ecu so should be able to check continuity down this wire,although I think it's probably an ecu fault which will be expensive.Have you had the car into a ford main dealer and put on there machine?I would think your auto electrician will get to the bottom of it.
Your starting/running problem is probably a different issue altogether.
I might try disconnecting ecu and try trace the wire to alternator,if I can get connector off ecu.Please keep posting any updates.Cantbelieve there is only us two had this problem.

[Tiles80]

Hi
Just got to the bottom of mine. Paid £700, new alternator and battery, still wasn't charge properly until the revs went above 1800 rpm. After a few days with an auto electrician, turned out a cable had wrapped around some control box linked to ecu had shorted out which meant the battery light came on and re demister stopped working. All fixed now but auto electrician said he had to strip loads of bits off and cut into loom etc. didn't help my alternator smart charge was a one wire instead of three like most. No one could help or identify which alternator was needed.

[shady]

Glad you got it sorted.I can't afford £700.Mine is also on the single wire smart charge.Do you have any idea where this control box that's linked to the ecu is do you?Its not behind the dash by any chance is it?

[Tiles80]

Hi
The electrician said it was a nightmare to get to, he had to strip my he tray underneath the car to get to everything. Took him 3 or 4 hours to strip everything to get to it