Yea, the L terminal should be OV not 2.5, so you have a fault in the wiring circuit. I haven't got any wiring diagrams, so that's the best I can do. Also check the fuse for a loose contact and the integrity of the battery connections and connections to the alternator. With the motor running, check the voltage at the battery, should be about 14V, turn all lights and a/c on and check again, if it drops to around 12V, your alternator is not charging properly.
best of luck, let us know what happens.
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