Yamaha F100B F100C Outboards Factory Service Manual, Page 332Get this manual
TRBL SHTG Bracket unit
Troubleshooting
Symptom: Power trim and tilt unit does not operateListen for the operation sound of the power trim and tilt relayCan the operation sound be heard? Yes Can 12 be obtained? Yes Listen for the operation sound of the power trim and tilt motorCan the operation sound be heard? Yes Can 12 be obtained? Yes Check that the manual valve is closedCheck the power trim and tilt motorNo Replace the power trim and tilt relayReplace the power trim and tilt relayCheck the voltage between the blue (L) lead and green (G) leadNo Check for continuity between the battery, relays, and switchCheck the voltage between each terminal Between the sky blue (Sb) lead and black (B) lead Between the light green (Lg) lead and black (B) lead