Fan wiring help

[Lasttruck]

Trying to install a maxxair fan as a replacement for the vent in the bathroom in our 2018 145rb.

When I connect the wires (correctly) to the feeds supplying the bathroom led light, there is no power to the fan or the light itself. When disconnected, the light works.

Any advise to resolve this would be appreciated.

Jim
145rb
Port Townsend, WA

[16WhiteColly]

Did you use a meter or test light to probe the feed wires for power and ground? The wire colors are backward from residential colors.

[Lasttruck]

I did test the wires for power and they did well until the fan was connected. Tested the fuse and found fault. Magnifier showed a hairline space in the fuse.

Further investigation is warranted as the fuse fault light (wfco8735) did not come on right away. The led light was getting enough juice to light dimly until the fan was connected, then nothing at all. After the fuse was replaced, the fan works and the light is bright.

Something is energizing that line, albeit with weak amperage.

BTW, I am well aware of the intricacies of RV wiring. This rig is new to us and I just finished adding 300 watts of solar (mounted on the truck to place in the sun/RV in the shade), 2000 watt PSW inverter (may add more battery capacity later), MPPT solar controller, shunt for the battery meter and re-wired the mess up front with individual boxes and busses for the positive side and the wires going to the converter. Amazingly it all works very well. This is the second rig that I’ve done this to.

Jim
2018 145rb
2010 Chalet xl1935 (sold)
Port Townsend, WA

[RobertC]

If the fuse panel has a "blown fuse" indicator it passes a small amount of current to make the fuse indicator light once the fuse blows. It is probably enough to make a small LED light work so that might be the reason the light worked before you connected the fan.

[Lasttruck]

Makes sense.

On the other hand, it would have made a nice night light! ��