As you have found , the supplied 'mount' is crap.
Even the holes do not line up ..it is just an off cut of stainless steel..utter shit..but the lights are good.
No idea about the yellow wire
But yes, the CA goes down and that is correct..the power is coming through the shunt on the bike, and the CA displays current flowing through the shunt. it probably reads about 0.25 ?
edit , just thought, does your CA have the separate speed sensor, the magnet sensor on the front wheel and not pick up the speed from the hub.
if o then that wire is probably the pulse sender for speed if you ditched the remote sender and used the speed sending from the hall pulses
Mongoose MTB, Fox forks,26x2.3 tyres, 180mm disks. 20s 20Ah LiPo, Lyen 18 FET,5304 in 26 inch EX721. 9k miles 2years
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