Testing The Battery, How do I make sure mine is dying?

After reading my fault codes yesterday the car wouldn't start. It barely turned over and wouldn't fire. Put the jump leads on it and it started virtually before I had turned the key which made me realise how much it has been labouring to start recently - a few seconds of turning before it fires up. Not too much labouring in the grand scheme of things, but out of sorts for the car.

Now I had done a couple of short journeys and a 'move the cars around the street' before, before doing a good few glowplug heatings by way of turning it off and on while reading the fault codes of all the computers, but I would have expected the battery to cope with that. Given the recent performance as well I assume the battery is on it's way out. It was a cheep one about 4 years and 2 months ago, so it is due to die by my reckoning.

However, I remember reading (and I'm sure it was on here) a guide to diagnosing dying batteries from the voltages it gave out at various times. I can't find it now though. Anyone remember it?

I am sure the alternator is fine. Engine running gave 14.5V at the battery terminals. Everything off gave 12.5V and ignition on (after glowplugs gone off) gave 11.6V. Does that last reading point to battery going?

I am in mind to go to the stealers for a new one. My previous experience is a 3rd party one will last a couple of months past is guarantee (2, 3 or 4 years - I assume my current battery had 4 years guarantee given the timing...) but a dealer one will last 7-10 years. Had this on Nissan, Peugeot and Citroen batteries. Besides, the stealers are no more expensive that Halfrauds, just a little more than the motor factors.

Hi Rowan,

Just before you go out and spend all that dosh on a new battery I sugegst a couple of quick checks. The boot light staying on is a favourite. The switch at eh striker plate gets a lot of abuse and can come adrift from the microswitch which should be attached.

If you can't find the current draw i'd put an ammeter in series with the main battery lead with everything switched off and take a note of the current. Calculate from the stated AmpereHours (AH) of the battery how long it should last. IF the current draw is higher than expected pull out one fuse at a time keeping an eye on the current. When it drops to a significantly lower level on pulling a fuse look up the chart to see what that fuse covers. Then disconnect/inspect/test those components one by one until you find your problem.

Alternatively, although I hate to say it, Kwik Cr*p will do a "Free" battery test for you with the proper kit. They will automatically tell you its duff so they can get a sale but if you know that then you can ask to witness the test yourself. From the results you can make up your own mind.

Hope that gives you food for thought.

Cheers

noz

Hi Rowan

Stealers battery 7-10 years!!!!!!!!!!!

Not Citroen!!!!!!!

I quote from 95XM07
Subject: XM Pre-delivery Inspection - Checking Battery Condition
If the battery is more than 12 months old it must be replaced.
If less that 12 months old check battery voltage. The battery must have been at rest for at least 1 hour.
If the voltage is below 12 volts, replace the battery.
If the voltage is between 12 volts and 12.3 volts recharge the battery.
If the voltage is above 12.3 volts the battery is in good condition.

Regards

XMexc

Check the voltage with the engine running, it should be around 14 volts possibly + a bit. You can check if it is being discharged by putting an ammeter in series with one lead and the battery terminal, it shouldn't read more than s few milliamps once the suspension computer has shut down. If all OK it will be the battery.

They are constructed in such a way, with lots of thin plates, that they will deliver enough power to start the car when probably 80% or more of the active material has been lost, but they have very little reserve power.

If you replace it get a decent one. GSF do their own brand for about £60.00 and you can tell by the weight of it its good. They are only as good as the ammount of lead in them, so a weight check is a good way to compare.

Peter.N.

They used to. On my old BX I replaced the original Citroen battery at about 9 years. I then replaced the Halfrauds replacement 3 years later.

I think my XM had the original battery when it was replaced 4 years ago which made it just over 10 years but it was rather dead at the end.

Wouldn't like to say for sure that it is the same now though.

I will have to look at GSF and my local motor factors. The stealers quoted £123 inc vat, and that is the same as the online place I found that does list the XM. Haven't tried Halfrauds.

I will do the current drain test first. It has started fine the last couple of days

To be fair to Citroen, the PDI check is for a battery that has stood idle since the car was built. If that is 12 months, I would replace it, too!

If memory serves, the biggest battery that will fit in the box is 096. Any factor will recognise that code. I've found Euro Car Parts to be very cheap for batteries, and good quality. If you're in Redhill, try Frenches Autos if they still exist, they were always pretty good value.

Neil

Hi Neilp

Fair cop. I realised the PDI battery check was a little unfair on Citroen but thought it was very interesting that they did not automatically put a new battery on a very expensive new car that had stood unused for a very long time. As PDI's were only issued following problems it seems that they first tried sending the cars out with duff batteries.

Regards

XMexc

I believe they are still there. I tend to get things in Horsham though as I work there so am able to get things during lunchtimes.

If I need things when I am in Redhill then it is an emergency at the weekend and then I end up standing in the car park thinking 'which is more likely to be of help, Halfrauds or the pet shop'