Ford mondeo mk4

[lucas26]

Hi,i have an issue with my car mornings when i start it the battery light comes on for some reason only when the temp outside is below 4degrees.is a common problem or i need to have a look into it.thanks

[dezwez]

Are you sure it’s the battery light and not the outside temp light just a thought 

[lucas26]

It's the battery light for sure

[lucas26]

It comes on when the outside temp light comes on.

[dezwez]

Is the battery a good one as it might be failing?

[lucas26]

Bought the car a year ago and had the ford batt on it,not sure if i need to change it

[dezwez]

Mines a 2008 and I just had a new battery as it was getting hard to start and that was a ford battery.

[lucas26]

But this is why i don't understand,no problem starting what so ever mine,the battery light comes on only when the temp outside is below 4degrees .

[Tdci-Peter]

54 minutes ago, lucas26 said:

no problem starting what so ever mine,the battery light comes on only when the temp outside is below 4degrees .

From what you say, I suspect an alternator fault more than battery.

It is worth checking battery voltage with a meter on the terminals, before and after a start. 12v to 12.6v before, and 14.2 to 14.8v after (idling at minimum electrical load, or with headlights, fan & wipers at about 1200rpm or more.) It may take a minute or two to build up after starting.

If the battery light is always exactly linked to the temperature light, it could be an instrument cluster fault.

I think the Ford charge system asks for higher current from the alternator in low temperatures, and if it can not deliver, the light may come on. So an alternator current check may help, but would need Ford specs. to compare it against.