Wiper motor issue

Windshield was iced. Attempted to run wipers. Too much ice to move them. Ruined wipers. Cleared windshield. Wipers no longer operate.

Facts:
- Fuse is good.
- Multi-meter shows 13.5 when touching fuse connections.
- Test light lights up when testing fuse connection. And the light dims/brightens as I rotate the wiper switch from intermittent to low to high.
- Wiper motor ran when bench tested with a boat battery.
- Wiring harness at motor shows 13.5 on the multi-meter.

When placing test light on the wiring harness that feeds the motor, the light is very dim. I have to cup my hand around it to confirm its (hardly) lighting up.

Is this a symptom of a short in the wiring from the TPIM to the motor? Or could it be the TPIM itself? I’m thinking not TPIM given the positive test results at the fuse.