Battery Advice

[philjb]

Hi, new member here,

 

I've got an '01 Mk II 2.3 LX auto, with 65K miles on the clock and found it with a flat battery last night. I'm not mechanically minded to identify any known cause other than possibly a) too many short journeys with too much draw on the battery or :( something was left switched on or c) the battery's had it.

 

Anyhow, jump started it no problem, put it on an overnight charger and it restarted fine today.

 

So my questions are, am I likely to face the same problems again and is there any other cause I should be looking for? Alternatively, should I just cut my losses and buy a new battery or will charging the current one intermitantly be enough of a solution?

 

 

Many thanks for any help anyone can give.

 

 

 

Phil

[big_kev]

If the battery keeps going flat check if there is anything drawing current when the ignition is switched off....there will always be a little current drawn...clock...alarm system etc.

 

A cheapo multimeter should suffice for this.

 

If there is no unexpected current being drawn then assuming that the battery is charging ok from your overnight charger then it may be the alternator ( or associated charging system ) that is at fault.

[insider]

If the cause was ":(" then, if you're careful not to leave anything switched on again it shouldn't happen again.

I doubt if "a)" is the cause because the alternator should be more than capable of charging the battery and satisfying the electrical load while the engine is running, even on short journeys.

As big_kev suggests, don't restrict yourself to just the battery as the cause - it could be something else either draining it or not charging it.

[Smilge]

One check you can do, with this cheapo multimeter as Kev suggests, is to measure the DC Voltage across the battery terminals with the engine running. You should get a reading of between 13.8 and 14.4V. Anything less than 13V and you're looking at a new alternator or wiring. This problem usually shows up on the dash as a "charging" warning light on and can be confirmed using the multimeter. How long have you had the battery and what type is it? If it's a maintenance free type then if it has gone totally "flat" then you may as well throw it. Also, certain batteries (Ca) require a special to type charger and so your Halfords charger is really not up to the job. Hope this helps.