VW Beetle 2001, Battery keeps DYING

[TabathaAsks]

Hey All,

Thanks for any help in advance!

We have a little VW Beetle 2001 as a runaround, It’s used maybe 2/3 times per week for short journeys to the supermarket etc.

We upgraded the radio in the car to a generic Bluetooth one from Amazon (cost around £20)... it was fitted by my husband who followed instructions and the radio was all up and running. I thought great! No more factory radio as all it had was cassette capabilities.

All was well for a few weeks, radio fine, car fine.

However around 10 days ago, I popped in the car to go to the hairdressers and it wouldn’t start, The radio came on and the dashboard lights etc so there was SOME power in the battery , however when turning the key to start it just made a clicking noise.

I put it down to bad experience and luckily a neighbour helped me jump start it and I took it on around an hours drive to get it charged up. I then used it a few days later and it worked perfectly. The last time the car was used was on Sunday for a 40 minute round trip to the supermarket and back.

I’ve went to use the car this afternoon and it has reverted back to not starting but having enough power to play the radio.

After researching online, I am beginning to wonder if it is the new radio that is draining the battery. However the radio goes off when the car is off so not really sure if this is the culprit ?

The car was MOT’d a few months ago and passed, and the battery is around 18 months old.

The only difference than before is the radio... Also it has been relatively ‘hot’ recently, so I’m wondering if the sun can cause this also ? (May be a stupid suggestion)

Once I can get someone to jump start it, I plan to take it for a good drive and this time leave the radio off and not use the radio for a few weeks to see if this makes a difference ? Or should I buy a battery charger and charge overnight and continue to use the radio ?

Any help would be much appreciated!

[greysquirrel]

Quick diagnosis. Take the radio out, see if it still happens over the course of a week. If it doesn't, it's the radio.

[TabathaAsks]

greysquirrel said:

Quick diagnosis. Take the radio out, see if it still happens over the course of a week. If it doesn't, it's the radio.

Thank you Grey Squirrel.

[Oscar011]

greysquirrel said:

Quick diagnosis. Take the radio out, see if it still happens over the course of a week. If it doesn't, it's the radio.

It seems to be pointing to the radio. You bought it then the problems are occurring. Your alternator seems fine as you said it started the next day or so which suggests it was charging the battery. You could Always get the cars battery tested which is usually free at most mechanics to test the battery and the alternator. This usually tells you if something’s draining your battery.

[GreenV8S]

The timing does seem suspicious and it seems likely you have a parasitic draw somewhere. As well as disconnecting the radio to see if that stops the problem, it would be worth checking for other parasitic loads. You can do that with a decent multimeter at the fuse box - I'm sure Google will give you chapter and verse.

If the battery has gone flat then it will take a long time to fully charge it just by driving the vehicle. It may be that it hasn't actually recovered fully from the original incident yet. It would be worth getting a battery charger to make sure. I suggest getting a smart charger which will stop charging when the battery is fully charged. They're commonly available and not expensive. After being run flat several times you will probably find that the battery itself is now damaged and has a reduced capacity.

[Penelope Stopit]

As mentioned by others above the radio wiring is suspect and the mistake of incorrectly wiring radios is made by many
Often it is found that there is a yellow wire and a red wire at the radio for powering it on/off and also giving it memory
Those yellow and red wires are often the culprits due to being connected the wrong way around

Edited by Penelope Stopit on Friday 25th May 19:04