How do you check for ground on aircraft wiring?

Answer 1

if the aircraft is the standard aluminum airframe. any power ground should be less than 1 Ohm. A digital multimeter is best for the novice. for more serious applications a mega-ohm meter should be used. but be careful, most of this meters output more that 600 Volts.

Answer 2

Answer for USA, Canada and countries running a 60 Hertz supply service.

A good way to check the continuity of a ground wire in the electrical system is to measure the voltage from the "hot" wire to ground. This voltage should read the same as what you would read from "hot" to neutral. The reasoning for this is because the neutral and the ground are bonded together at the distribution panel main breaker enclosure. If the neutral was not connected you would either not get a voltage reading at all or you would get a reading of a lower voltage that you would expect due to resistance in the circuit.