Battery light then esp then dead 😳

[Christian]

Haven’t posted in a while owing to the car being trouble free.My battery light came on in my 2006 2.7tdi the other day then went on and off for the couple of times I drove it but when driving home tonight the light stayed on then a warning for esp light came on then the main headlights dimmed and my dash and mmi went dead. The engine stayed on and Thankfully I was close to home so got it back and locked up. I’m obviously concerned that it’s the alternator but has anyone experienced this, could it just be the battery or worse than all could it be the alternator pulley AND the alternator. Your advice would be greatly appreciated.

Cheers 

Chris

[Magnet]

Hello Chris,

This is obviously a battery or charging system fault , and if you have a multi meter and are handy with it then you can fairly easily find out which. I doubt if your battery is the original after 12 years, but it is possible. If it is, then you have done well, and it would be more likely to be this that is at fault - but you will still need to confirm the alternator output.

I would suspect that this car now has insufficient battery power to start the car, but if it does start, a fairly simply test for basic charging is to allow the car to tick over for a few minutes then switch the headlights on, then observe if the headlight brightness increases as you rev the engine. No increase in brightness suggests a charging issue. 

You should find that Halfords or others will be able to check your charging system quite simply -while you wait . If OK and the battety is a fault then buying a replacement at Halfords?? If it were mine, I would find a trusted local auto electrician and get them to check this out for you. 

One other basic test you should do, is to check the serviceability of the alternator belt. This may, just may be the cause of the problem, but should be eliminated as the culprit. Suspect alternator belts giving way, wrapping themselves around the crank pulley and causing cam belts to slip are not unheard of. 

If the car won't start and you need to jump start it then please make sure you know what you are doing before connecting jump leads or you can cause all sorts of expensive problems. 

Kind regards,

Gareth.

[Christian]

Thanks for your reply Gareth. I’ve had a good mechanic friend of mine over this morning who strongly believes it’s the battery. We couldn’t fix it today just because nobody had an appropriate battery in stock. The car did start over and it does appear that the battery is indeed the original one!!

After a couple of minutes of running it started smoking from the exhausts - a result of the injectors not getting the help they needed apparently. All belts seem quite intact and Undamaged so I’m hoping that a quick battery swap should take care of the issue. Is there anything I need to be prepared for after I do swap it though?

Kind Regards 

Christian

[Magnet]

Hello Chris,

If the battery is the original one then you have done very well indeed. Personally, I would get your mechanic friend to check the alternator output as well - a simple check with a simple tester ( were even available from Lidls at one point) - since nothing should be assumed without testing to confirm the suspicion. 

I take it he will have the necessary 'code saver' device to ensure your radio code (if it has one) is protected during the battety change. 

Kind regards,

Gareth.

p.s. It's always worth buying a premium brand battery with at least a 4 year guarantee. These can usually be obtained at very competitive prices on line - often with next day delivery.

[niedzial1983]

FYI 

Battery chanrge should be around 14.2v . Also new battery should be codded in 

[Christian]

Ok I’m getting a little worried about changing this battery tomorrow now! Has anyone got a step by step guide so I don’t goose the thing when I’m doing it? I’ve just ordered a code saver device but I don’t suppose that will solve this battery coding issue???

[niedzial1983]

You will need a vcds or obd11pro , mabey carista  to code in battery

But if you will replace like for like ( voltage amps ) you dont need to code anything

[Magnet]

Sorry Piotr, but I'm confused. Why would Chris want to change this battery for one which isn't compatible with the one he has? Surely volts = 12v , and I take it you are referring to cold cranking current when you refer to amps. 

Chris, 

Where are you getting this battery from? If you are buying local then they will usually replace it for you. If not then best to ask your mechanic pal to do it for you. When you use the code saver, you usually need a spare battery to feed the code saver - which gets plugged into the cigar lighter while you remove the old battery and replace with the new one. 

Kind regards,

Gareth. 

p.s. Having said all that, as I said before, you are still assuming it is the battery which is at fault until you test it and/or check the alternator output is as Piotr says. 

[Christian]

Getting battery locally from euro parts, and will definitely be checking the alternator when we’ve fitted it. I haven’t got vcds however.

[Christian]

Well it turns out it’s the alternator 🙁 put the multimeter on and it’s only showing 8.2 whereas my battery shows full. The car is misfiring at about 1400 revs and I guess that as a result of the charge not being enough to run the engine properly. I’ve a friend coming over to help fit it with me tomorrow. Does anyone have any tips they can pass on?

Thanks 

Chris

[Magnet]

Hello Chris,

I must start by saying I don't take any comfort from offering advice to actually check components rather that assuming they are serviceable or unserviceable. In this case the battery was 'assumed' to be the culprit, yet the then-untested alternator later proved to be at fault. 

Unless you are lucky then this experience has cost you the unnecessary purchase of a battery. You need to get your mechanic pal to buy you a drink - at least! 

Someone once quoted the word Assume as meaning:-      'Making an !Removed! out of you and me!' 

With apologies for rubbing it in.

Kind regards,

Gareth.

[Christian]

Cheers Gareth, I Never bought the battery- just ordered it to be held thankfully, I’m no fan of spending unnecessary cash that is for sure hence the attempt to remedy the matter without a visit to my local garage.....The £10 for the multimeter was money better spent !!. We are going to tackle the replacement tomorrow and my original alternator will be reconditioned and put back on. I’ve got a few links for tips to do it without removing the front end completely and I’ll let you know how we get on....as always any guidance or tips are welcome 😳😬