Help Big Foot 25RQ electrical issue

[Rzrbrn]

I have a 2019 BF 25RQ with cargo box. The outside 12v lights over the cargo box and over the 30 amp receptacle will not switch on. I checked with a meter and also just by shorting out between the switch poles. Nothing, apparently no power.
I bought two new Arcon Oval porch lights #20679 to replace the same OEM fixtures. I tested just before I removed and the side light came on but not the front. I removed the fixture, cleaned the sealants off and connected the new fixture using quick connect blade type connectors on the wires. I was not able to pull out the mfg's wire nuts, through the little hole in the surface of the trailer, wing nuts were too big and were very secure anyway. I just cut the wires coming out and installed the blade connectors. I them reconnected and...no lights. Neither the side nor the front would switch on.

I then took the new light fixture apart again and all connectors were tight and secure. I reinstalled.

I then went inside and tried to trace the wire from the 12v fuse panel to the splice or junction of the wires to where they might come together, thinking something might be loose. I could not find any such junction, splice, or connection. The connection on the fuse panel was secure.

I am a loss as to what to do next. Any thoughts or ideas will be appreciated. As you can probably tell I know nothing about electrics.

[Alex Adams]

Were the lights you replaced incandescent? The fixtures you used are LED and if the polarity of the incoming power is reversed, they will not light up. I would double-check that first.

[Rzrbrn]

The OEM lights were LED. The replacement lights are LED also. Thanks for your response.

[AC0GV]

Originally Posted by Rzrbrn

The OEM lights were LED. The replacement lights are LED also. Thanks for your response.

You did not say what you checked with the meter. Did you follow the voltage to the light? If so, reverse the wires. Not all LEDs care about polarity but most do.
Some of mine do not matter and in fact will run on 12 AC.

[Dan Meyer]

Try your new light on the bench with a good, fully charged 12 volt battery.



--Dan Meyer

[Rzrbrn]

I don't have a good grasp of electrics. I just stuck the probes on the two metal tabs coming out of the switch in the light fixture. I did reverse but only because I did not know if I was doing it correctly. No power.

I have 4 BattleBorn fully charged batteries in the trailer, and it is connected to 30 amp shore power. In order to try the light on the bench I will have to take it off the trailer. This is a good idea. At least I will know if the new switch is any good. I will try this tomorrow. Thank you for the suggestions. I will be back later tonight to check on this thread.

[AC0GV]

Originally Posted by Rzrbrn

I don't have a good grasp of electrics. I just stuck the probes on the two metal tabs coming out of the switch in the light fixture. I did reverse but only because I did not know if I was doing it correctly. No power.

I have 4 BattleBorn fully charged batteries in the trailer, and it is connected to 30 amp shore power. In order to try the light on the bench I will have to take it off the trailer. This is a good idea. At least I will know if the new switch is any good. I will try this tomorrow. Thank you for the suggestions. I will be back later tonight to check on this thread.

Measuring voltage, follow the voltage from the battery, through all switches and wires. The problem will be located between the two locations where you do and no not have voltage. I have over the years found bad wire, bad NEW fuses, and bad factory connections.
Please let us know what you find.

[Bruce Olive]

I assume the replacement fixtures came with new switches. On mine, I ended up replacing all the OEM switches with new. They all work fine now. Hope you can resolve this issue.

[Rzrbrn]

Yes the new fixtures come with switches.

I have a clamp meter. I wonder if running the wire through the clamp can be done for 12v to determine if there is current?

[Bruce Olive]

Well, they did work and then they did not. My theory based on similar fixtures is the switches went bad and the replacements are suffering from reversed polarity. As mentioned earlier in the thread, many LED fixtures are highly sensitive to polarity. Have you tried to reverse the wiring of the new fixtures?

[Rzrbrn]

Bruce I just wired the new one like the OEM fixture since they are the exact same item. It won't destroy the switch if wired in reverse will it?

[Bruce Olive]

Also, a 12 VDC test tool is only $10 or so at any auto parts store. Basically a probe with a flashlight bulb and a wire with an alligator clip. Very handy for RV DC testing. Good to have in your took kit. Best of luck.

[Bruce Olive]

Switch will be fine. Worth a shot.

[Rzrbrn]

Thanks for the tip Bruce.

[Arthur II]

Originally Posted by Rzrbrn

I have a 2019 BF 25RQ with cargo box. The outside 12v lights over the cargo box and over the 30 amp receptacle will not switch on.

Sent You A Private Message ....


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[Rzrbrn]

I took the trailer in to the RV service center. The switch in the light fixture over the 30 amp receptacle was bad and has been replaced. The light fixture over the cargo box was replaced. The fuse for these two fixtures was blown. I checked that fuse a number of times but sure enough it was blown when the RV tech pulled it. Oh well...Both fixtures are now new and attached with butyl tape and finished with ProFlex sealant. I bought two new waterproof switches which I will have a backup.

Thanks to everyone who responded.

[AC0GV]

Originally Posted by Rzrbrn

I checked that fuse a number of times but sure enough it was blown when the RV tech pulled it.
Thanks to everyone who responded.

I have had fuses look good and be bad many times. Most people look for the "black" of a blown fuse, but they can just vibrate open or even be bad when new. The best way is to test for voltage on both sides of the fuse.

[Defenestrator]

If you don't have an easy ground point to test against, you can also either pull the fuse out and continuity-check it, or measure the voltage across the two sides of the fuse (anything but ~0V means it's bad).

[Bruce Olive]

Glad it’s fixed.

[Rzrbrn]

The RV tech that worked on it this time is an electro an with a great deal of experience and he showed me how to clean the fuse with my merger.

Turns out when I took it in the first time the fellow that worked on it “tested” the circuit by holding a screwdriver across the switch posts, one of which sparked, I saw it happen. He had previously checked the fuse and it was ok. I thought he knew what he was doing and the thought it was a nifty way to check to see if the line had electricity. The electrician said don’t do that, and is what blew the fuse. This electrician also identified the errant switch right off.