Rear light problems

[jrod101]

Ok guys I have a problem with my rear lights. Parking lights work and hazards. When I break the bottom red lights dont come on only 3rd break light. When I put the blinker to the left both side come on as if hazards were activated. If I put the right blinker everything works normal and front work as it should. I tried putting new lights and problem is still there. Any suggestions. Thanks

[Morich]

Not knowing what RV you are dealing with makes any real guess pretty useless. Could be something as simple as a former owner miswiring the lights for a trailer connection. Or lots of other things can go wrong if it is old enough.

[Eagle5]

This might be a Class B, as the Class As and Cs do not use the third high-centered brake light.

[jrod101]

Its a 2002 itasca sunrise 34d. My bad

[Eagle5]

Oops; sorry about the "lack of center brake light" comment. I didn't think Class As had them. As Morich said, it could be the trailer light connector causing the sneak circuit. I would start there, looking for physical damage, and take the connector apart.
Good Luck; Eagle5

[Eagle5]

Also, disassemble the tail lights and see if they are corroded or have a poor ground. I believe a lack of ground on the left might cause this.

[jrod101]

Sounds good will disassemble it tomorrow I did put new ones and the connectors look clean but could be further down

[jrod101]

Would it also cause for the stops not to come on only the 3rd light?

[Eagle5]

Originally Posted by jrod101

Would it also cause for the stops not to come on only the 3rd light?

The high-center brake light might be triggered by a relay.

[jrod101]

Oh okay. Tomorrow is another day. Thanks

[Winterbagoal]

Originally Posted by Eagle5

Oops; sorry about the "lack of center brake light" comment. I didn't think Class As had them. As Morich said, it could be the trailer light connector causing the sneak circuit. I would start there, looking for physical damage, and take the connector apart.
Good Luck; Eagle5

My (class C) Navion has the "cylops" brake light.

[Morich]

The problem in this is that Winnebago does a pretty good job on giving us some info but it is aimed more at the portion they add, not the parts which come on the chassis they buy already built. That leaves many of the things like lights,horn, turn signals to be on the part which they do not give us info as it has to come from the chassis folks and those folks often guard that as "top secret" stuff to keep their repair places in business.
If you need to know about your light at the steps, this drawing will tell you all kinds of things on page three but if you need to know about brake lights, we get nothing and can't say which fuse or even which box it is in!
http://www.winnebagoind.com/diagram/...ire_140647.pdf
As a general "guess" it may be that the wires from the right side come down, meet the bundle from the left side at a point underneath and near the trailer connection before heading to the front. you can sometimes locate which wires for the brake lights by tracing back from the trailer connection. that connection is often "standard" fitting this info:
https://www.f150forum.com/f4/7-pin-w...diagram-34265/
NOTE:
This is pretty close to guess but the best I have!

[Chappy]

Shooting from the hip here...before going too crazy with diagnosis, I have seem some pretty strange lighting problems caused by a bad ground wire or ground connection. That is the first place I would look regardless of what make and model you have. (Just a thought)

[Morich]

Just as a more general idea, I think you have several different circuits involved. You have the stop light and two of three seem to work, the left and right turn signals seem connected when turning left but not when turning right, etc. That leaves to look for a point where all those circuits come in close contact.
One place that happens is near the front like the steering column but also at the central point where the wiring bundles tend to be bundled together near the hitch. I might first want to look at the wires near the rear for physical damage or corrosion where wires may be getting together enough to make all kinds of weird things happen. A rock thrown up in the wrong spot or dragging the hitch, perhaps? The turn signal/light switch can do some weird things when it feels like it but I lean away from that as I would expect that to involve ALL the brake lights, not two out of three.
It can be a bear to find!

[jrod101]

I will tackle it today hopefully and see I can find the problem. Thanks for all the advise. I will keep you guys updated of what I find. Thanks

[Rick 99037]

On systems that have a single. dual filament bulb on each side, where one filament is for running lights, and the other brighter one is for turn signal and brakes; the turn signal lever on the steering column interrupts the brake light signal, to connect the flasher when the lever is pulled for Left or Right signaling. If this switch goes defective, you can get any number of odd conditions. One such problem is you still get proper signaling, but no brake light. Sometimes this is intermittent, and wiggling the signal arm will have things work again - for a while. If this is the problem, you use a steering wheel puller, to pull of the steering wheel, to get at, and replace the turn signal switch. I'm guessing retail automotive parts places loan a puller, so no need to buy one.
Another brake light/ turn signal bulb interrupter is the 4 way flasher circuit. When you engage the 4 way flasher switch, it opens the circuit used as a brake/turn signal, and connects the warning flasher. Try engaging and disengaging the 4 way flashers several times, and see it it reconnects to your brake/turn signal system. Also, seeing the flashers work or not work is a great way to verify your brake/turn signal bulbs are working too. Remember, what I've written here is only applies to the single bulb with dual filaments type lamp system.

[AndyAk]

First, in less than bright light, check each function.
Does one side look brighter than the other???

A lot of problems can be caused by defective and/or corroded bulbs.

Pull the lenses and pull the bulbs.

Actually check both filaments with power to be sure they all work.

A bad ground (as several people have mentioned) can make crazy stuff happen. In some cases, with a bad ground, it "backfeeds" through another filament, usually causing it to be more dim than it should be.
Just spend a few minutes on bulbs before getting into the wiring or your steering column.
And yes, if the towing plug looks home-done, look there second.

[Wyatt]

Originally Posted by jrod101

I will tackle it today hopefully and see I can find the problem. Thanks for all the advise. I will keep you guys updated of what I find. Thanks

I’d just love to see some photos, that helps a lot—I’m a visual kinda guy...

[dacap06]

Originally Posted by Chappy

Shooting from the hip here...before going too crazy with diagnosis, I have seem some pretty strange lighting problems caused by a bad ground wire or ground connection. That is the first place I would look regardless of what make and model you have. (Just a thought)

I agree with Chappy, bad grounds cause weird problems. The other thing that causes weird problems like this is use of the wrong bulbs. Your camper is old enough that all of them have been replaced at least once. Check all the bulbs in each light cluster that is misbehaving to ensure they were replaced with the correct bulbs. Match the numbers on the bulbs to the numbers in your owner's manual. If it is unclear what the bulb should be, call or write the manufacturer.

[jrod101]

Checked all grounds all connections and still can pin point the problem I guess its time to take it and get it check.