When I activate the windshield mist function with wipers no washer fluid comes out. I checked the windshield washer (WSW) 25A fuse in the fuse box inside the passenger compartment on the driver side and it was not broken. I installed a new washer pump and it still didn't work. I connected a volt meter to the electrical contacts that connect to the pump, and it did not ready any voltage when the mist function was activated. If the pump is not getting power and the fuse is good, then what else could be wrong?
Either the switch is bad or there's a break in the wiring due to corrosion.
Gain access to the windshield washer switch connector and check for power on the red wire. If you have power at the switch and not at the pump there's a break in the wiring. If you don't have power on the red wire check the yellow wire for power. If the yellow wire has power replace the switch. If theres no power on the yellow wire than either the fuse/fuse box or path to the underhood fuse box is bad.
Check for a good ground at the washer pump by doing a voltage drop test from the pump connector to the battery negative terminal.
Uhg.. I finally figured out I just wasn't doing it right. I found in most other cars you push or pull the control lever to activate windshield washing. In Impala's, there is a tab on the lever that you push to rotate the lever. It worked the whole time. I should have looked at the lever more carefully to see the windshield washing icon on that tab.