1987. Why is there no power at the turn signal cam?

flashers and turn signals have separate flasher and separate fuse.

many lighting systems use two flasher relays to isolate turn signal function from hazard function. each has an independent power supply source path or circuit. you'll need to trace power to the bulbs from the turn signal switch, and from the fuse boxes to the switch.

you may have a bad flasher relay. its also known as a hazard relay, or turn signal flasher.

It's not a relay , it's a unit flasher or tung sol
it is located Under dash steering column
activate four way flasher by the click sound find it
the flasher unit look alike
hope it help

did you change the flasher relay ? it controls the flashers and the hazard

Maybe a relay or fuse is bad or the wiring to it.

But you said that the third brake light works.

So the brake switch must be ok.
Turn signals would be the flasher or wiring to it.
CIRCUIT PROTECTION Fuse Block Fig. 1: The fuse box is located under a cover at the lower left instrument panel — 1987 Voyager shown
The fuse block and relay bank is located on the driver's side under the lower instrument panel. The fuse block contains fuses for various circuits as well as circuit breakers, horn relay, ignition lamp thermal time delay, and the turn signal flasher. The hazard warning flasher is mounted into a bracket below the fuse block. The individual fuse and relay locations can be found in the wiring diagrams at the end of this section.
is bad.

Typically there is a seperate relay for both the turn signal and hazard lights; I expect the hazard relay has failed. These may easily purchased ( $5.00 or so ) and replaced. The attendent at the auto parts store should be able to give you placement of the relay location.
I hope this may have helped,
Tom

check your flasher the Hazards have a seperate flasher its a littl cube that looks like a relay in or near the fuse box

i have a similar problem but my left signal works, when i turn the right on it just does an annoying buzz sound. if you can think of any explination for such shinanogins help would be greatly appreciated

There are two flasher units,one for the turn signals,and another for the emergency,or 4 way flashers.There is a possibility you replaced the wrong flasher unit..