I fixed battery draining problem

The beetle has had a battery drain problem, which was not evident until it didn't get used every day and sat for a couple of weeks. The battery is good, the generator is charging well, so I checked with a multimeter and found that the stereo was draining 0.29A of power when everything was turned off. I thought it seemed quite high for a radio memory.

Upon further investigation it appeared that it had been installed with the main power wire to a permanent fuse, and the memory power wire to an ignition sourced fuse. This was making the memory wire operate as a switching wire somehow to turn the unit on and off, but in a power draining standby mode.

With the wires swapped to the correct way, the power drain for memory is now measured at 9.83mA which is less than 0.01A, being about thirty times less than before. Technically this means it would take a year to drain the power it was using before.

Just thought I would share my experience of something I learnt, and maybe it can help someone else one day. 😊

i owe you a beer!

i'll owe you two beers if you tell me exactly where you put the wires.
i've had the same problem but i'm not sure exactly what you mean.
i also have a sub powered directly from the battery with an inline fuse and switched by a wire from the head unit.
battery goes flat in 3-4 weeks with minimal use? i also tested for leakage and know there is a current drain there somewhere ?
maybe 3 beers.

Great Work...

Glad you got it sorted out..

LEE

Hi Phil,

It is a simple CD headunit with the wire colours being commonly used as three headunits I have ever fitted have the same colours.
Red - main power
Black - earth
Yellow - memory wire
Blue - Amp switch/ power antenna switch wire

The rest are audio wires

I put the Red to an ignition powered fuse. Wipers are an example

I put the Yellow to a permanent powered fuse. Interior light for example

Hope that helps

philew wrote:i'll owe you two beers if you tell me exactly where you put the wires.
i've had the same problem but i'm not sure exactly what you mean.
i also have a sub powered directly from the battery with an inline fuse and switched by a wire from the head unit.
battery goes flat in 3-4 weeks with minimal use? i also tested for leakage and know there is a current drain there somewhere ?
maybe 3 beers.

ok...i get it ..thanks helbus.
three beers it is.