What solenoid? There are dozens on a car, I suppose in a '77 Maverick not so many as modern cars, but sometimes 7 Volts could be normal, depending on what it switches on/off. But if you mean starter, either battery or solenoid it's self is not passing current. (does it start and run?)
Check the battery connections and have the battery tested. 7 volts at the starter solenoid is not enough.
No fire, starter solenoid, let me tell yall quickly what happened, mavrick wouldnt cut off .Replaced switch&coil. Wont start now, belive its wire.
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