that thing you pictured is a attachment plastic tip that plugs into a mount for the harness.
NOTE a trickle charger is not a battery charger.
go buy a battery charger that makes 2 amps and 6 amps,
and disconnect the ground on the battery,
and charge the battery for 4 hours at 6 amps.
NOTE get a can of Deoxit 100 ,
while thats happening clean both battery terminals ,
make sure that both terminals are tight ,
check the grounding points
put D100 on everything you touch,
From the POS terminal, follow the red wires to the junction points make sure to clean as many junctions as you can find.
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