Battery light flashing

[Qldmts]

I have a mk6 H9FA 2.4 TDCi common rail engine in my transit.
Today the battery light started flashing.
I checked the charging with a clamp meter over the wire coming out of the alternator and it was 4 amps but would drop to zero each time the battery light flashed.
Something that I also noticed was even when charging at 4 amps when checking the battery voltage with a meter it still only showed 12v and not an increase when the engine was revved,most cars show an increase when you rev them.
Any thoughts as I can see me having a flat battery soon?

[Frag]

If the light is flashing,It could be that the one way clutch in the alternator pulley has failed.

[knobby1]

Alternator brush pack/regulator is another common fail point.

Lord Knobrot

[karl]

If the light is flashing,It could be that the one way clutch in the alternator pulley has failed.

mine did this and was recon out of the box only was on for a month could tell a story about that night as well

it goes like this

alternator light comes on after a finished job so didn't chance it home on the motorway so went back to the customers place to borrow another vehicle so could get home, so sets off flying down the motorway and the 4x4 just cut out in the fast so costeded across all for lane to the hard shoulder
and had to organise me own recovery for their vehicle as theirs would be hours and mine was 30 mins another night to remember

[Qldmts]

Any thoughts on why I see no voltage rise when revving the engine when the battery light is not flashing?

[trannynick]

Afternoon all. Having same issue, - Although had aux belt screeching a lot, changed belt and tensioner 2.4 tdci - Was ok for a hundred mile, then screeching came back at certain rpm, then battery light started to flash and when checked battery has 12.5 vaults to it with both engine running or switched off, did try and get a reading from the alternator terminal whilst engine running but was getting low readings at best. What would be the next port of call, is there a fuse or a regulator to check before replacing alternator or any other tests i can do?Finding info for the mk6 2.4 tdci is rather scarce. Youtube is uselss now aswell, all promoted rubbish when searching. Many thanks.

[metalworker0]

The regulator is in the back of the alternator .. and you have to know what you are buying before you replace it .
that's almost impossible if you are not a reconditioner .. or had lots of experience

a guess to what has happened ... the screeching was the alternator bearing failing, this caused metal swarf to be distributed into the alternator - the electronics within shorted out and failed

buy a new alternator

all the best.mark

[trannynick]

Hi, ive taken the alternator off and it spins quietly, however the clutch mechanism on the pulley is grating and can spin either way without turning the inside of the alternator when spun with force, doing it slowly allows the alternator to spin and it seems quiet. Pehaps just fitting a new clutch pulley would solve my problem?

Ive just span it up with a star socket on a drill, sounds terrible, yes new alternator time, i would have it refurbed but its an aftermarket rotek and doesnt look that old, does anyone know what the original alternator brand that would be on these, is it ford/bosch? Thanks.

[metalworker0]

I don't have any experience of alternator clutches at all ... but i suppose,as you say - if its completely buggered, it would not spin the alternator or generate power , so may solve your problems, if a new pulley is purchased, available on ebay £15 - £30.

all the best.mark