Mooney M20E io360 low voltage problem

Mike Harvey writes:



Thanks for the response. It could be a bad connection to the ground.
As previous stated and to further clarify, I usually keep a trickle
charger on the battery and when I first go flying the battery before
starting is 13.5 volts. and no noise on the radio. When I get back
the voltage is 12.5 or less and I get noise on the radio. I've had a
tech check out the antennas and no problems and com1 was recently
overhalled last year. Com2 does not experience any problems. I don't
have a generator but I don't know what type of alternator it is. Need
to look at the log books


First, buy a voltmeter. You can buy a quite usable DVM from Harbor
Freight for $3-$5, depending on sales. I own about 4; one in the car,
one in the toolbag, etc.

Then use it to measure the battery voltage ON the battery terminals.
With the master off, etc. it should be at least 13.5 volts.

Can you safely start the plane and still get to the battery?

With the aircraft at least running; it should be above that. With it run
up a little, it should hit 14.4.

Then add loads; lights and pitot heat come to mind. You should still
be holding at 14 volts.

If not, something is wrong in your charging circuit. What do the panel
instruments say?
--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433