I may be wrong here, but:

I have never used the MX3660 but the manual says that the 4 general purpose outputs are open collector. This indicates that the output can sink current from the + terminal (Collector) to the - terminal (Emitter). You have the + voltage connected to the - terminal. This would be backwards for an NPN transistor.

Normally you would connect it up like this:


The - output connected to ground will sink the current required to bring the + output low when the output is active. The resistor will pull the + output high when the output is not active. You can change the outputs active state to high or low in the configuration.