Battery Draining

[marcparry]

Recently I seem to be having issues with my battery draining very fast but only occassionally. For example:

 

I drove it Monday morning then left it to sit until wednesday evening when I went away. Returned wednesday and it started fine first time. Tried to start it thursday morning, completely dead! This has now happened 3 times on 2 different batteries. Now onto my third battery and I'd like to find the problem before it happens again.

 

Any ideas where to start looking or would it be best to call an autoelectrician straight away?

[techbod]

have you fitted an aftermarket radio? check if its left on all the time,

does the cooling fan come on when its parked up? coolant temp sensor fail,

see if interior lights go out when you lock the car up and also the one in the boot,

check all the earth wires to the battery/chassis/engine if they break down with dreaded green fluff it will create a live circuit

[marcparry]

have you fitted an aftermarket radio? check if its left on all the time,

does the cooling fan come on when its parked up? coolant temp sensor fail,

see if interior lights go out when you lock the car up and also the one in the boot,

check all the earth wires to the battery/chassis/engine if they break down with dreaded green fluff it will create a live circuit

 

All the lights go out and I checked the boot one too. Can't here anyhting from the cooling fan and the radio is the standard fitted one. The only thing I had fitted was a parrot bluetooth kit but that was in for over 12 months before problems started. i have since removed this incase that was causing the problems.

 

I will check the earth connections tomorrow to see if i can see anything causing problems there. If not electricians I guess ...

[techbod]

electrics are one of those areas that are harder to pinpoint without being on the job and with the proper tools to check it out,

I have a good collection of tools just for that but one way without the tools is a battery voltage drop test and that can be done with a cheap multimeter connected to the battery if something is live all the time then removing fuses one at a time would point to the fault but its one of those jobs that takes time so good luck with it

 

http://www.engine-light-help.com/voltage-drop.html

[paul.h]

Is the alternator charging up the battery when the engine is running ? If you have a volt meter, with the engine off you should see about 12½ volts at the battery, with it running it should be about 14 volts. If not then possibilities include the alternator could be faulty, the drive belt loose or missing, alternator wire/connector loose/broken.