Battery light

hi, my wife’s battery light remains on in her freelander2 when engine running. I’ve checked battery in car 12.6v? Checked alternator that’s outputing 13.6v anybody got any ideas?

So you've got a voltage drop of 1v from the alternator to the battery. You need to find a poor connection that is causing this. Measure the voltage, with the engine running, from the alternator case to the battery negative. Then, measure the voltage, with the engine running between alternator + output and battery positive.

Which ever one gives you the 1v - this is the line to check out for poor connections. Most probably a poor earth from engine to vehicle or subframe.

Good luck, logical measurements will find it !

If neither has a volt drop then it could be that the battery is charging and the indicator is lying to you - suspect internal alternator diode fault.

Need to check alternator output with all electrical loads on - heated screens, seats, headlights, main beam, front and rear fog lights etc etc.

Alternator should output c14.4v in this condition.

do not for get to put you brake lights on as well in fact anything usually they just glow and can be seen more in the dark when you put your foot on the breaks but I also would go with a alternator ,have you been wading lately in deep water .

there has been a issue with bad earth from the battery

td4van said:

Need to check alternator output with all electrical loads on - heated screens, seats, headlights, main beam, front and rear fog lights etc etc.

Alternator should output c14.4v in this condition.

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Just tested the alternator, 13.6v at tick over, then put on all electrics, lights, a/c,heated screens etc, alternator still outputing 13.6v.

Is your volt meter reliable? Does it display the correct voltage?

I would say your alternator is knackered and you need a new one!

Check AC ripple at the alternator B+ terminal. Should be <0.5V even under heavy load.

Got the problem sorted. Got some advice to check blue wire from alternator, see my picture. The wire had very little visible damage, looked crushed by cable protection, but I cut it and re-crimped it. Warning cleared. Thanks for all the help