Right brake light out...

[scenic route]

Rt brake light out. Lt brake light OK along with all directional signals. V/A meter confirms no power to the bulb socket...socket wiring disappears into a large loom. Checked the main chassis fuse panel's smaller panel (2A) and found a brake 5A fuse...checked good but replaced anyway - no help. All wiring I could see looked good.

A couple months ago I did notice that the right brake light was dimmer than the left and last week it went out. I'm wondering if there is an additional fuse chassis panel somewhere for the right side or there may be a ground somewhere that needs some attention.

Starting a 2 month trip the 20th of this month and I'm electronically challenged. Any ideas? Thanks

[Argosy]

When you checked voltage at the socket did you use the socket ground terminal or a chassis ground? If you used the socket ground and it's bad it will show 0v on the hot line.

[Melster]

Sounds similar to a bad ground!

[scenic route]

Originally Posted by Argosy

When you checked voltage at the socket did you use the socket ground terminal or a chassis ground? If you used the socket ground and it's bad it will show 0v on the hot line.

Ahh...Never occurred - will check that out tomorrow. DW's birthday today so I'd be wise not to get too involved and forget about the time - as usual.

Melster: Was my thinking, was hoping someone would know where the ground is located. Monaco is good at protecting their wiring (bundled).

[Old Scout]

Easy to check ground at socket--if the issue, forget the loom, just sort out a good ground point in proximity and rewire.

[scenic route]

Originally Posted by Old Scout

Easy to check ground at socket--if the issue, forget the loom, just sort out a good ground point in proximity and rewire.

Thanks, if it's got power I'll do this. Hopefully, I'll know more tomorrow.

[Arch Hoagland]

Let us know what you discover...curious minds would like to know.

[scenic route]

Originally Posted by Arch Hoagland

Let us know what you discover...curious minds would like to know.

Will do... Did sort out some other issues today, but the V/A meter was left at home.

[scenic route]

Still at it... There's no power to the socket, so I'm thinking there's another chassis fuse panel hiding somewhere. I did find a broken bulb contact tang in the socket, may be why no power?? Anyway, it needs to be replaced - have number and it's a auto parts item, we'll see.

I'm finding out these MHs do not like sitting around. Checked the gen oil level and the slide out quit sliding after closing. It just never seems to quit.

[Jchemie]

Money pit! Welcome to the club! You said that this light was starting to dim prior to it finally going dark, that would indicate a connection becoming corroded somewhere down the line, or even a wire pulling out of a terminal and only a strand holding on. Fuses are either working or not, they don’t just allow 1/2 power thru. Sockets themselves go bad, I’ve seen that happen many times on older vehicles. Do your voltage testing a few inches back before the socket, use a wire piercing tester to check for voltage. Don’t just rely on using the terminal inside the socket.

[LETMGROW]

I would never suggest someone use a probe to pierce a wire. Unless you seal the hole up you made when piercing the wire it will come back to bite you in the butt sooner than you may think. If there is no other way to test the wire cut the wire, test for voltage at the end of the wire then cut the insulation back, slide a length of heat shrink tubing over the wire sliding it back far enough to where you can join the wire back together then slide the tubing over the splice and using a heat gun warm the tubing to where it shrinks tightly to the wire to prevent air from entering the splice.
If you leave the pierced spot open to the atmosphere at sometime in the future you will have a corrosion issue and the wire will rot away and form an open circuit. Then you'll have to do a proper repair eventually anyway. (After you find the problem)
In my long career of working on cars, trucks and many other types of vehicles and equipment I have found a large number of corroded wires which caused an open circuit due to someone having pierced a wire and not sealing the spot up properly.

[Jchemie]

In my many years of working on vehicles (owning my own business & working for other shops), the only problem I encountered with corrosion as you have mentioned, was with exposed crimp butt splices or where a person sliced (hacked, better term) the insulation then using cheap electrical tape to seal them up. Pin holes won’t cause a problem, only if the wire is drenched repeatedly in water and salt. If I had a concern with a piercing, then a dab of silicone over it solves the problem. Besides, how could you slide a shrink tube over the wire if both ends of it are connected permanently or attached? Kinda hard to do. If that tiny hole is such a problem, then why isn’t there a hugh issue with corrosion at the end of EVERY wire connection where a lug is attached and the wire is exposed to the air? All plastic connectors allow some exposure, abit more than a pin hole ever will.
The problem to look for is a possible bad solder joint in the positive wire in the socket or the wire coming off. He said he had tried re-grounding it, now check down the line for the loss of current. There was no mention of back probing the socket, you know, the big exposed space behind the socket. He mentioned the fuse was tested good but replaced anyhow. So now time to go fishing down the line from bulb to fuse either by piercing or fox & hound methods.

[Old Scout]

Curious, without a voltmeter, how do you differentiate between "no power" and no ground?

[LETMGROW]

Jchemie,
I see you are from Arizona. You don't have the same atmosphere we have here in Northern NY state where the roads get a heavy dose of road salt all winter long into the early spring. I have repaired countless rotted out wires due to exactly the conditions I described in my original post. Trailer wiring especially is a real PITA up here.
Yes, I too have a long experience of working on motor vehicles and heavy equipment from the time I was 16 years old employed in a service station, moving on to three different dealerships then becoming self employed for the last 36 years running an Auto Care repair shop and the last 20 years of which I also owned and operated an automotive machine shop. All told this was a span of 61 years before I sold out and started enjoying the fruits of my labor.
I don't throw things out there just to type away on my computer. If what I offer doesn't have merit I won't waste my time pushing these keys. I would have nothing to gain by it. On the other hand someone who read my post might have something to gain by my efforts.
Have a good day.