The vehicle is a 2000 expy with 4w/d and a 4.6 windsor engine, vehicle has 200,000 miles. Here is the situation. I have no turn signals but do have emergency flashers and wiper function. I have replaced both the turn signal flasher and relay. I have also checked connections in steering wheel and they seem OK. Yesterday I was checking the flasher with a test light and when probing the turn signals both right and left worked with the test light connected. When I remove the test light the turn signals no longer work. Any ideas ?

 

Where were you probing? Did the turn signals work with the lever or just went using a test light. Oh and was the test light self powered?

 

I was using a regular test light( clip to ground probe to power light comes on.)I was probing the terminals at the flasher ,key was on and lever was in signal position. There was a wire for each side.

 

Sounds like bad ground or power lead from the switch - would have to do one at a time to see which resolves the issue.

 

Thanks for the help, removed mulltifunction switch and found loose wire.