Mitsubishi Repair & Maintenance Questions? Ask a Mechanic Online
as this is a modern 'smart' alternator the current control is run by the ECU but the testing of it all is a bit more involved
see here for a detailed description
I suspect that something is wrong either with the ECU controlling the current, or the earth connection between the ECU and engine or its the wrong spec of alternator
if you find where the small earth wires are fixed to the engine and then run back into the main wiring loom as these are the ECU specific earth paths and used to control supplementary function like this
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