Ford Focus 2.0 TDi GHIA (2007) - Battery Light on Dashboard Fault - takuhii


I have a 2007 (07) Ford Focus 2.0 TDCi with a bit of a weird fault;

Yesterday (06-Aug-2014) the battery symbol lit up on the dashboard. I took it to a local garage that diagnosed my car with a dead/unservicable battery and a faulty alternator and quoted my £400 to fix it (I have the heavy duty 80aH battery and potentially the 150A (ma?) alternator.

This morning (07-Aug-2014), however, I took the car to another local garage (a more independent one), the dashboard battery light is still on BTW, and they've told me that the battery and alternator are fine, the battery is holding charge and seems healthy (they tested it with a multimeter), and the alternator is spitting out approx 14.7, and maintains this under load. Their auto-electrician has confirmed that the wiring is also sound and their appear to be no faults at all, so they want to put another alternator on the car to test it/potentially fix it :/

What I'm asking you good people is... Have any of you come across a similar fault before, and if so what was the cause and potential solution?

I'm concerned as if this is an ECU issue, I could be looking at a very steep bill.

Any help would be greatly appreciated

Ford Focus 2.0 TDi GHIA (2007) - Battery Light on Dashboard Fault - elekie&a/c doctor

Most modern Ford models have a smart charge alternator and charging circuit that runs through the engine control unit.It is a common problem for a fault to develop in the alternator and/or its wiring to give the issue that you have.The alternator can run in default mode and still charge at 14+volts,but put the light on.It is important that the wiring to the alternator is checked corectly before the alternator is replaced.The most common wire to give problems ,is the small battery sense wire(usually red).If there is not a good voltage supply to this wire , the smart charge system will not operate correctly.

Ford Focus 2.0 TDi GHIA (2007) - Battery Light on Dashboard Fault - takuhii

Thank you very much for your prompt reply :)

It's been to a proper auto-electrician, so I would hope he's checked this, I've just verified with the garage and they've said it was the first thing he'd checked. So hopefully a new alternator will fix the problem, as least I hope so ;)



Ford Focus 2.0 TDi GHIA (2007) - Battery Light on Dashboard Fault - takuhii

Just wanted to say SPOT-ON!! The Alternator was replaced and all is fine again.

The new alternator looks a little different to the old one, but the old one had a strange white corrosion all over it, this one looks like a monster. I have the kick-ass 150amp alternator, so it looks like it could power a small country at the moment :/

Once again, many thnaks forthe help and insight, much appreciated :)


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