On the outside of the vehicle, in the area beneath the drivers foot-well there is an electrical connection for the starter motor. This is the start motors main connection to the battery. It is possible that this connection may be causing an intermittent restriction in current flow due to corrosion. Disconnect your cars battery on the ground cable side, remove all the wires at this foot-well connecter block. Wire brush the terminals so they are clean and bright afterward reconnect the wires to the terminal block. (You may find that a 1/4” drive ratchet may be best for this repair).

SPECIAL NOTE: Do not over tighten wire connections! I mention this because I believe everybody wishes to avoid unwanted down time waiting for new parts.

Reconnect your battery ground cable then recode your radio.