I have a 2004 Chevy W3500. The turn signals do not come on, nor do the indicator light on the dash come on. The emergency flasher do work properly. I can hear the flasher unit clicking rapidly. I did replace the flasher and there was no change. Any other ideas?
Remove and check that each bulb is grounding in the socket and there is no corrosion behind the socket.
Also. check to ensure NO bulb has a double filament stuck together.
Use a continuity tester to see if power is getting PAST the flasher.
A fast activating flasher (more than normal) usually leads to a burned out bulb or bad socket.
Check your brake lights. When the multifunction switch goes bad the brake lights are usually the first thing to go after the turn signals.