Community Forums

bogey1112 · 12-02-2020, 09:47 PM

I am having an issue with my electrical system. With NO tow vehicle hooked up my exterior marker lights come on. They come on regardless if Im on shore power or battery. Even on shore power with the converter / charger operating as it should the lights are draining the battery. If I remove the 4th fuse they go off, and the battery doesn't discharge. I believe I have some sort of short in the DC wiring system or is there an on/off switch for the exterior marker lights somewhere that I am unaware of. I understand the electrical 7 prong plug has a circuit dedicated to charge the battery while being towed and plug in. I would have to believe the circuit would run thru the DC side of the electrical panel. Can someone identify the fuse (if any) this circuit would be associated with. Or any ideas no locating / troubleshooting the issue. Thanks in advance

Skip426 · 12-03-2020, 07:48 AM

Welcome to iRV2.

The power cable to the tow vehicle , should have a junction box where the cable ends and connects to the trailer system, sometimes the connectors are in a 6"x6"x2" box . If the cable to vehicle plug shows no sign of damage then finding the box and checking inside for wiring problems is the next step .

Some owners hook the marker lights up to a switch so they can be put on at night for finding their RV , so look for any added wiring if this is a new to you trailer.

The lights should not draw enough power to drain the battery when on shore power ; so you may have a converter or battery problem too.

bogey1112 · 12-03-2020, 08:34 AM

Trailer is new to me .. just replaced the converter / charger as the charger portion was out .. charger output is in range .. tested lugs at charger, at dc panel, and at battery .. all showing same voltage .. any idea why removing the 4th fuse would turn the marker lights out, other than a short or purposeful connection between the two seemingly to me unrelated circuits .. thought is .. whatever caused the other charger to fail is related to the marker light issue

Skip426 · 12-03-2020, 08:47 AM

Any indication what the 4th fuse should be powering ?

What 12 volt system doesn't function with that fuse out?

By" in range " for converter output , what voltage ?

Have you charged the battery from a separate charger and had it load tested?

bogey1112 · 12-03-2020, 09:08 AM

The charger was pushing around 14 volts .. with the battery down below 12 .. now that it has charged for a while .. all three positions referenced are at 13.2 .. with the battery charged it passed the load test .. currently trying to determine what #4 fuse operates .. will update once / if we can identify the circuit .. also wiring plug is good / clean / seems to have no issues .. working on tracing the trailer wiring to see if we can find the junction box you mentioned .. will update ..

Skip426 · 12-03-2020, 09:25 AM

I'll check back in a few hours .

Good hunting , maybe take a few extra mins and check and label all the fuses .

I can't figure how the converter output won't power the lights and still charge the battery.

bogey1112 · 12-03-2020, 09:43 AM

The only thing we can find on #4 fuse circuit is a single light over the sofa .. we have a total of 15 marker lights .. but even that would result in pulling maybe 7-8 amps per hour .. and again no reason for the lights to be on that circuit unless someone added a switch we cant find or there is a short .. will keep looking .. will advise with updates .. thank you very much for the info .. got to find the gremlin hiding amongst the wiring ..

Skip426 · 12-03-2020, 12:37 PM

As with all electrical repairs , pinpointing the problem takes 95% of the time involved.

The marker lights , should not run through a fuse in the trailer , they would be powered and protected through the tow vehicle wiring and fuses.

You mentioned the marker lights and one interior light , go out with the #4 fuse removal , and the battery doesn't discharge ; but is the battery still charging with that fuse out ? What amp is the #4 fuse ?

bogey1112 · 12-03-2020, 03:16 PM

The #4 fuse is 15 amp .. the panel has 11 circuit fuses .. 9 are 15 and 2 are 5 .. we will need to discharge the battery a bit to see if the "smart" charger will work with the fuse out .. but from what I have been able to observe I would say yes it charged wit the fuse out .. and agreed that the marker lights "should not" be in any way involved with the DC panel for the living quarters .. unless the previous owner thought it would be "cool" to be able to run his marker lights with the tow vehicle unhooked .. Ive read that some folks do that ... trying to make contact with the previous owner to see if he can answer that question .. will advise ..

bogey1112 · 12-04-2020, 03:17 PM

I believe we have at least narrowed the issue to the functioning of the slide out .. the slide out has been extended during this process .. the sofa light controlled by the #4 fuse is in the slide out .. so we started there .. found some evidence of non factory wiring (appears someone other than the factory has messed with it) .. when we retracted the slide out a few inches the marker lights went out .. the quest continues .. have to be away for a few days so won't be able to work on tracing the wires until we return next week ... in the mean time going to be searching for a wiring diagram ....

Skip426 · 12-04-2020, 05:29 PM

Thanks for the update;

Wiring diagram ; if you can find one ; could be so generalized , and next to useless, it might not be worth the time to look for it;

some 12 volt wiring will come down to who was working on the assembly line the day your RV was produced .

Different fuse/relay, locations between my coach and others built the same year , have shown me that.

bogey1112 · 12-09-2020, 07:38 PM

Haven't found the exact cause of the problem .. but have narrowed it down to the wiring running thru the slide out bar mechanism .. of course now we cant get the problem to repeat itself .. but going to keep looking ... will update if we ever find an exact cause ..