My can can only reverse when I unplug the gear brain box but can drive with the brain box fixed
Check for shorted or corroded wiring to the transmission control unit. Is water leaking jnto it?
Yes the wire is very wet and the brain box is very hot when engine is switched on
well if its wet your giving the water a open invitation to spark all over the place which will likely short out your computer tcu (transmission control unit) take it out let it dry then reseal the box and make sure the cables are not wet and try it out again.
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