I had one wire that just fell out of a crimp connector when all I did was touch it, pffft.
The awning reverses direction by simply reversing the polarity the switch sends to it. If you pull the switch off the wall, you'll find 2 incoming wires - one is pos. and other is neg. If you measure the voltage there, do it with motor not running (open circuit voltage) and with motor running. If it dips a lot while motor is running, there's a bad connection downstream of the switch.
Poor ground connections often cause problems. That can be a challenge to track down, depending on where connections/splices are. If it is a bad ground somewhere, you might be able tie into a nearby ground wire if possible instead.
If voltage at the switch is good, then the motor is the likely cause (or connection at it). You could test for presence of 12 volts at the motor terminals too.
