1) try substituting a different mic or two. The second problem a radio runs into is a broken mic wire down by the plug. The first is an antenna that is not tuned.
2) what is the voltage that is feeding the radio. It should be between 12 and 14 V. If the power is too low for some reason it won’t key-up.
3) ground will be coming from the power wire. Disconnect the coax from the radio to make sure that is the case. Fix the ground wire if necessary. The complaint states that the meter and Tx light are not working. They should work if there was no antenna connected to the radio.