MG Car Repair: Electrical problems with an MGB, low beams, high beams

Question
I have a 1978 MGB and lately my battery has been going dead for no apparent reason. It takes a couple two or three days for the battery to go completely dead. last fall I had a corroded battery wire. The one that runs from the battery to the starter, so I repaired it and all appears to be okay there, and it has been running and starting just fine. I also have a problem with my headlight switch, when I turn on my headlights I have no high beams only low beams. I thought this may be the problem so I removed the light switch, left it unhooked and still within three days my battery went dead. If you could give me some idea of where to look next I would be very grateful. Thanks, Dave

Answer
Hi Dave.  You have an electrical drain from somewhere, so you must find it.  

The headlight switch is permanently live, and there is no fuse in the circuit so the switch is permanently live.  However, you pulled the wires from the switch, so that eliminates the lighting switch.  

The only other live items are the interior lights and the horns.  You can eliminate them by pulling fuse #4.  

Do you have a light in the boot (trunk)?  If it doesn't switch off when you close the lid, that would be enough to drain the battery in two days or so.

The loss of high beam is a separate problem.  It could be a loose or corroded connector.  Check if the main beam flasher still operates.  If it does, the dipswitch is faulty.  If it does not work, then the problem is with the wiring to the main beam.  

Check the blue dash light.  If the blue light doesn't come on, then it is a faulty dipswitch.  If it does come on, the problem is with the connector under the slam panel in front of the radiator.  You are looking for a connector with 3 wires going into it.  All the wires will be blue with a white stripe.