[MikeK]

Start by unplugging the flasher. The three terminals should be labeled P, L, X and laid out like this:

For the record, P = pilot light, L = lamps flashed, X = fused battery source.

If the problem is not a defective flasher there is one common wiring error that will present itself as you describe. - incorrect wiring to the flasher socket or a short between the "P" (pilot) and "L" (load) leads to or at the soldered connections for the "P" and "L" wires in the SS900 switch.

The indicator should be wired to the "P" terminal ONLY of a three wire flasher. Connecting the pilot ("P") lamp to the "L" (load) terminal will cause it to light constantly, except when the switch lever is in the right or left position. Then it will blink. The problem as described is exactly why flashers are made with a separate, isolated relay contact, labeled "P". Nothing other than the pilot lamp should be connected to that terminal.

There is absolutely no need to have any switched battery source in the turn-signal circuit unless you wish it to be non-functional while parked. Wired correctly, it will draw zero power unless activated by the lever. I however, am a big supporter of having a cutoff switch in the battery ground lead.