The Fan-Tastic Vent 3300 has a three-speed fan selector, a powered roof lid, a bulb thermostat and a rain-sensor circuit. This model's Dometic drawing identifies the 12-volt supply path, lid motor, control board and switch connections separately, making it easier to find the component you need before ordering a replacement.
Original Dometic 3300 wiring schematic
In the 3300 schematic, the 9050-90 A board operates the lid circuit; the three-speed selector also supplies the fan motor. The fan's on/off and lid-position switching is drawn as part of the motor-ground path. Do not substitute a board solely because a different Fan-Tastic model has a similar layout.
Open the full-size Dometic PDF to zoom in on the wiring and connection numbers.
Wiring callout reference
The identifiers below follow this model's drawing. Use the diagram for actual terminal locations and routing; the table helps locate the corresponding wire number or connection.
| Callout | Wire / part reference | Function in the drawing |
|---|---|---|
| 1a | WS-0342-09 | 16-gauge black lead from 12V positive supply to the 4A fuse |
| 1b | WS-0110-09 | 16-gauge black lead from the fuse to the three-speed selector |
| 1c | WS-0633-89 | 16-gauge red feed from the speed selector to the fan motor |
| 1d | WS-0410-81 | 16-gauge yellow feed from selector to PCB 12V+ |
| 2a | WS-0264-81 | 16-gauge white supply ground feeding PCB 12V− and thermostat |
| 2b | WS-0264-81 | White return from thermostat to fan on/off switch |
| 2c | WS-0170-81 | White return from fan on/off switch to lid switch in base |
| 2d | — | White wire from lid-position switch to fan-motor ground |
| 3a | WS-0602-88 | 18-gauge red lead from PCB dome motor positive to 17 RPM lift motor |
| 3b | See schematic | Black/white return from PCB dome motor negative to lift motor |
| 4a / 4b | 9051-91 / see drawing | Orange pair between PCB three-pin plug and dome up/down switch |
Photographs of related Fan-Tastic service parts
These are actual NewRVParts product photos to help identify the kind of component being serviced. Match the original manufacturer's part number, colour, connectors and production version with the individual listing before ordering.



Confirm the correct vent before ordering
Use the 3300 model label and compare the fitted PCB marking, switches, motor-cover finish and connector arrangement. Replacement parts can change across production dates; a 17 RPM specification by itself does not identify the complete lift-motor assembly.
