Charging odditiy.....

[RichardW]

On the way to work this morning, and the charging light came on on the Xantia. D'oh. Clearly not charging as he lights were dim and wipers slow. Turned round to head home, but it then went out, and stayed out all the way to work (another 25 miles). Repeat performance on the way home I'd thought about a loose wire, but it doesn't seem like that as it was all or nothing, no flicker or anything. Can only think the alt has gone on the blink I replaced this only 2 years / 30k ago, with a refurbed exchange unit (TWICE, as the first one was DOA). Perhaps the regulator is away - any thoughts? I think the unit now fitted is a Valeo - I think these have a bolt on reg unit, so maybe I can change that. Otherwise new alternator time

[Xantidote]

If you're saying the alternator stopped charging, and then started again, then think I'd be checking the wires/connectors at the alternator to start with. Having eliminated that, I'd have a look to check the alternator's brushes are Ok in their holders, and 1 hasn't stuck. I wonder if a tap with a hammer on the metal part of the alternator would encourage a sticking brush to behave (until alternator removed for checking)?

[RichardW]

I think it's thrown in the towel this morning - worked OK for about 20 miles, then nothing after that (apart from a very brief return to charging at one point). Wonder how far an HDi will go with no charge. In the dark and wet.... Just checked for loose wires and gave it a clonking, but no change. My guess is the regulator has gone down, given that it can charge OK when it wants to. Can't see any numbers on it though, so it would have to come out and be stripped to get a replacement part, which I probably don't have time for (unless anyone happens to know the part no for a reg for a Valeo 150A alternator off hand ), so will have to renew. £125 on the bay for a new one so not disasterous - a bit annoying though as the refurbed one cost nearly that....

[addo]

To be intermittent really makes me suspect brushes; I had one that was doddery for a while, then the brushes finally exceeded their wear limits and actually fell out (or, what was left of them) leaving the spring rubbing feebly on the slip ring.

[Mandrake]

I was going to say brushes too, especially if the alternator is already a 2nd hand replacement...

Is there any way you can measure the output of the alternator before the regulator ? Or is the regulator internal to the alternator housing these days ? (The last alternator I had to fix was on a GS, none of my later cars have ever had alternator problems, so I'm a bit out of touch )

[RichardW]

It was a 'refurbed' unit, so I'd assume had new brushes - but maybe not....!

The regulator and brushes all come as one unit, and are bolted right onto the alternator itself, so no way to measure the output pre regulator. I gave it a clonk this morning, but that didn't shake it back into life. Pretty sure you can't get the reg off with the unit in the car - it's not that bad to get out, having already done it a couple of times. You do have to remove the oil filter - but at least you can do it without having to disturb the hydruaulic pipes or cooling system!

[Xantidote]

it's not that bad to get out

Well, it's always easier to inspect something closely when it's on the bench. Question is, do you take it out now to have a look, & then put it back so the car's driveable, or do you get a replacement first, without knowing the problem.

If you are still using the car, hope you are able to carry a spare battery - good luck, and no breaking down away from home

[RichardW]

Wonder how far an HDi will go with no charge.

About 45 miles.... just as I got home, things were going downhill, with ABS and air bag light coming on, and the radio going off each time the load was increased (like putting the brake lights on!). Will get it out and see what's what - battery now on charge so SWMBO can use it tomorrow as she only drives around locally.

One down side to driving without and alternator though is that the blower doesn't work as it takes it run signal off the alternator output! As it was only just above freezing here, I was pretty chilly by the time I had got home

[Mandrake]

Interesting about the climate control - its probably a protection mechanism so that if the alternator does fail the blower fan (which draws a LOT of current on higher speeds, up to 20 amps on full speed) doesn't needlessly run the battery down and prevent you getting home... there is an "engine running" signal to the climate ECU that the Lexia can report, I assumed that it just took a signal from the engine ECU but apparently it must measure the voltage from the alternator!

It is possible to force the climate control fan to run at half speed with a Lexia even when the engine is not running using actuator tests, but that's hardly a convenient workaround

45 miles is not too bad if you had the headlights on as well, without the headlights on you would have got a lot further maybe 3 times as far, around town during the day would be ok, although if that involves a lot of starts you'll drain the battery quickly with the starter on a diesel... Every start is probably worth 10-20 miles driving as far as the battery drain is concerned...

[RichardW]

Replaced the alt today and normal service is resumed, both on charging and blower front.

Not sure Simon if the blower takes a a direct signal off the alt, maybe it's just the ECU reading the voltage and not allowing the blower if the voltage is below a certain level. Oh, and on the HDI, the major power user is the socking great electric fuel pump in the tank.

[Mandrake]

Are you going to attempt to diagnose and repair the faulty alternator ? Might be useful not just to have a spare on hand but also to find out why they keep dying...

[RichardW]

£25 surchage on the exchange unit, so it will be going back. That's not to say I might try and open it up in the mean time, but I did have a quick go on Saturday, but you need a very slim wall socket to remove the bolts holding the cover on by the looks of it. Just unlucky I think - the original was changed at 107k because the bearing was noisy (and I think the brushes were about shot) - this one just stopped charging (it's done 30k in 2 years though). I suspect since I was getting a strong ignition light that the brushes were OK in fact and either the reg has gone open circuit to earth, or the diode stack has chucked in the towel. Replacement one has 2 year guarantee - that will probably see this car out....

[CitroJim]

Replacement one has 2 year guarantee - that will probably see this car out....

Doubt it Richard, I'm sure the car will live much longer than two years

[RichardW]

Dunno, 2 more Scottish winters will not be doing it any favours. And if it starts needing repair every weekend, will not do much for domestic harmony either - although by then the apprentices will be nearly 3 and 6 so getting in the realm of being outside with me rather than inside annoying SWMBO (albeit Dillon thought it was a bit cold on Saturday after an hour or so working on the alternator - actually I thought so too, but going inside to watch TractorTed on TV wasn't an option for me.... ).

On the up side, I think the old one's outut must have been down for a bit - have had a few cold starts of late when I thought battery was down a bit (it's been on this car 4 years, and over a year on a ZX TD before that - and it's only a bog std Halfords job). However, since fitting the new alt, cranking speed has been well up, so the output from the old one must have been down a bit.

[charentejohn]

I read another post by the OP the realted to this and thought I would cross reference with one I did - http://www.frenchcarforum.co.uk/forum/v ... =3&t=42720" onclick="window.open(this.href);return false;
This related to changing the regulator and brushes unit with the Bosch alternator on the car, cost around £20-25 if you shop around, so as someone suggerted worth a try before buying a new one.
The regulator and brushes are all one unit and once you know the part /alternator number you can find these from many sources so shop around.