Xantia V.6 intermittent charging light

[Stickyfinger]

es9j V.6 engine on my Activa:

Battery charge light comes on below 3.1/2 rpm
Goes out over 3.1/2k for a sec or two then back on again. It will not stay OFF if I hold the revs at 3-4k rpm
Belt not slipping, good tension
No LHM dripping onto alternator
All wires in good condition on the alternator

There is a short burst of charge when it hits the rev range above (14v) but hard to test on my own as it is such a short time window to test, no charge when the light is on.

Change Alternator ?

[Hell Razor5543]

Brushes on their way out? I had this happen on my BX, and I was able to get replacement brushes from Thames Valley Electro Diesel in Reading for around £15 (but this was over ten years ago).

http://www.tved.co.uk/

[xantia_v6]

I have never had an alternator failure on an ES9 engine, actually, I have never had an alternator failure on any car that I have owned, although I used to help my dad professionally repairing them... but my first Xantia V6 got to 200,000 miles without wearing out the brushes.

With those symptoms, it could be almost anything, brushes, regulator, rectifier ...

If the alternator has previously had LHM through it, there could have been long-term damage to the brush gear (due to arcing).

[Stickyfinger]

I have two V.6 ones on the spares shelf, just change it rather than mess about ?

[white exec]

Check the connections/feeds to the alternator. Apart from the main output (main output cable to battery, engine Ground) there will be a couple of +12v input feeds, one permanently Batt+ (voltage sensing), and the other Batt+ via the IGN switch. Both these needs to be operational for there to be any alternator output, which extinguishes the battery/charging light.
Connections to alternators do vary, but this is the typical set-up. The voltage-sensing connection is sometimes not used.
My main suspect would be the IGN-switched feed.

[Stickyfinger]

Chirs, all wires are intact (raining atm so I am limited)

It does charge for a sec/two at 3-4k rpm then the light comes on again.

Can the bushes be changed without removing the alternator ?

[white exec]

Wires intact, but is there a solid supply, particularly on the 12v input(s)? Put a meter on each one to check.

[xantia_v6]

I think the es9 has just a 2 wire alternator. Changing it is likely to be required, but I recall reading that it is not an easy job, because the pump and radiator are in the way.

[Stickyfinger]

Yep, EVERYTHING is in the way

[Stickyfinger]

Ran with the light to Halfords, got two cans of contact cleaner.
Charge light out about half way back, came on again 500yrd from home.
Parked up, idle, still on.
Rev'd the #### out of it and it was flickering, turned it off
2 cans of contact cleaner sprayed into the alternator and forced deeper with an air line.
Started it up and no light.
Waiting to try again later with toes crossed it was cr#@ in it.

[white exec]

Looks like bushes, then.

[Kerek85]

Deffo alternator has decided to retire.

[Stickyfinger]

Up date:
I improved it, but it was still flashing ect.

HP Pump pully off
ECU box and stuff out
AC Compressor off (pipes left on - supported on plastic oil drum)
Accessory Belt off (I also swapped the crankshaft pulley as it was "loose")
SWAPPED Alternator for a nearly new recon unit saved from the Green Goblin

[xantia_v6]

Congratulations on making it sound easy.

[bobins]

And the price if you got it done at a garage.......

"Well Sir, we won't fit second hand parts and we can't fit you in until next Friday and it will take a couple of days. Cue: <FX> Sucks on teeth..... "It's only an estimate, Sir, but we should be able to supply and fit for under £300"