Battery light coming on

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Post Reply
adamskibx
Posts: 250
Joined: 29 Nov 2004, 01:46
Location: United Kingdom
My Cars:

Battery light coming on

Post by adamskibx »

Hello-Driving back to the Midlands from Portsmouth yesterday night I noticed my battery light comes on if you turn the air blower on- Is this normal or is the alternator or battery on its way out? Its only dim and doesnt seem to be getting any worse. Regards, Adam
Stinkwheel
Posts: 562
Joined: 28 May 2004, 01:02
Location:
My Cars:
x 1

Post by Stinkwheel »

cant speak for BX's adam but all the CX's I've ever had do that to some extent or another.
Never developed into anything worse. I iimagine its just the extra pull through the alternator and maybe an iffy diode allowing a bit of back flow.
czenda
Posts: 136
Joined: 07 Oct 2004, 00:17
Location: Czech Republic
My Cars:

Post by czenda »

How about checking alternator drivebelt tension before digging into more complicated things, like checking sticky/worn carbon brushes inside the alternator?
goldfinche
Posts: 128
Joined: 08 Jan 2005, 02:29
Location: United Kingdom
My Cars:

Post by goldfinche »

Hello It could be that the ignition switch contacts are begining to burn up and are going high resistance.As the current for the heater goes through the switch it can fail with age as the contacts are only just and just man enough when new.Is the switch getting on a bit?
Does the ignition key get hot? Bad contacts will cause the ign. or charge light to glow.
Cheers.
Geoff
zzf00l
Posts: 238
Joined: 12 Mar 2005, 13:15
Location: United Kingdom
My Cars:

Post by zzf00l »

Check the voltage output on the battery whilst engine is running with 'everthing' switched on, should record 14+ Volts
adamskibx
Posts: 250
Joined: 29 Nov 2004, 01:46
Location: United Kingdom
My Cars:

Post by adamskibx »

Thanks people- ill check the alternator belt and brushes first- The ignition could be getting on a bit too- 158000 miles under its belt. Thats probably the one thing on this car that hasnt been replaced-service history shows literally everything else has been renewed.
sooty
Posts: 464
Joined: 31 Jul 2002, 00:34
Location: United Kingdom
My Cars:

Post by sooty »

I had this sort of problem some years ago on another car. It turned out to be the Alternator brushes were worn and had to be replaced, but this was a Lucas model. I dont know if you can get spares for Alternators today or you have to get a new or exchange unit.
PeterMann
Posts: 151
Joined: 02 Dec 2003, 08:10
Location: Australia
My Cars:

Post by PeterMann »

If you buy brushes that are slightly larger, they can be sanded down to required size.
dnsey
Posts: 1538
Joined: 20 Oct 2004, 01:39
Location:
My Cars:
x 19

Post by dnsey »

Replacement brushes are certainly available for Bosch alternators - I did a BX one a few years ago. Nice easy job (for once).
adamskibx
Posts: 250
Joined: 29 Nov 2004, 01:46
Location: United Kingdom
My Cars:

Post by adamskibx »

Yeah ive checked the belt etc all seems OK so ill replace the brushes. I have heard of people sanding down incorrect brushes before too- a mate with a 2CV ran out of battery on a night time motorway run- the AA man came and filed some big brushes down to fit.
czenda
Posts: 136
Joined: 07 Oct 2004, 00:17
Location: Czech Republic
My Cars:

Post by czenda »

Huh.
My experience with brushes is based on Magnetti-Marelli alternator - pls remember this before reading any further.
BXs were fitted with alternators coming from at least 5 different manufacturers (Paris-Rhone, Bosch, Mitsubishi, Valeo, MM, Iskra - which makes six, but it can be that Iskra was one of them made under licence). How very Citroen-like.
Each of these can come in sub-variants the number of which is unknown. This makes indentification of brushes by type of car/alternator extremely tricky.
Now comes my personal experience and very simple piece of advice: Remove the brushes from the alternator and take them to the dealer. Measure them and the black magic of Citroen dervishes will become clear at once.
If you can not bring the brushes to the shop, measure them and buy the brushes BY DIMENSIONS, not by the type of the alternator. It will save you a lot of time and nerves and petrol-money.
Soldering them back is E-Z job.
Sanding down the brushes does not seem to be a good idea - they are made of pressed carbon and the outer layer is thicker, if you sand it off, you will end up with the softer core that will be going to heaven sooner than later.
Any opinions are welcome.
JohnT
Posts: 344
Joined: 27 Dec 2003, 21:29
Location: United Kingdom
My Cars:

Post by JohnT »

I would first check for 14+ volts and clean contacts, and the earth from the battery to the body, and from engine to body etc. I have found that the small sigle wire coming of the unit is prone to partial breakage as it wobbles about over the years. Interesting comment by czenda, having modified brushes many times I was not aware that the outer surface was harder. I presume this is to allow for the wear in the guides. In future I will use the correct ones where possible, but it aint easy to locate new bushes seperately. Anyone know a specialised source for them?
Post Reply