How to onlock the keyless chuck of my cordless

if the chuck is rusted start with some WD-40 on the chuck body. Then what I would do is take a rag and wrap around the chuck collar and using a pair of channel locks grip the collar with enough pressure to hold but not break it and using the tool in the low position pull the trigger switch SLOWLY and see if that doesn't free up the chuck. Let me know if still stuck and I will come up with something else, but this usually works for me.