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. 😊
helbus Administrator Mad fabricator, paint and body
7,386 posts · joined Sep 2002 ·
