No brake lights

[Pacerized]

I'm planning to take off for a trip to the Redwoods from Colorado this Thursday but have an issue that I need to overcome. When I was testing my lights using my Durango I have no brake lights. I've also tried checking this with my truck and have the same issue. I have turn signals and parking lights just no brake lights.
I think the turn signal filaments are the ones that should turn on with the brake lights. I've also checked my 7 pin connection and 12 volt fuses in the airstream along with my bulbs. Any idea where to look into this next?
Suggestions would be greatly appreciated.
Thanks: Charlie

[garry]

Try this site different manufacturers have different color codes.

Trailer Wiring Diagrams | etrailer.com

Also Google for more ideas

[Pacerized]

Originally Posted by garry

Try this site different manufacturers have different color codes.

Trailer Wiring Diagrams | etrailer.com

Also Google for more ideas

I have my original airstream book that has the wiring diagrams. The colors seem to match. What I do have for turn signal lights are very weak and I've been looking for a ground issue. I regrounded the 7 pin white wire where it comes into the airstream but that didn't really help.
Do you think it's a ground?

[cwf]

First, diagrams must be verified. Second, if your truck has separate turn and brake lamps you may have an adapter module that converts turn and brake from truck to use the "turn" lamps for both turn and brake in AS.

I would use my TEST LAMP to verify truck is working first. Then proceed to trailer.

If poor ground, many issues can come up so check that on trailer AND truck.

To properly test circuit for balanced resistance which can affect brightness, use a VOM meter to check ohms and continuity.

[idroba]

The brake lights and the turn signal lights are the same bulb, same filament. The tow vehicle determines if they will be steady, both sides (brake) or flash (turn). Unless your tow vehicle has separate brake and turn bulbs, if your turn signals work on your trailer, your brake lights should also be operating.

My best guess is some issue with your tow vehicle(s). Seems strange both would act the same though, unless both have different bulbs for brake and turn lights.

There also is some question in my mind about grounding in the trailer lights, and what you are seeing is actually a flashing running light, not the real brake light filament. Are the turn signal lights quite bright compared to the running lights when on? If not, look for a ground issue at the lights.

[Pacerized]

Originally Posted by cwf

First, diagrams must be verified. Second, if your truck has separate turn and brake lamps you may have an adapter module that converts turn and brake from truck to use the "turn" lamps for both turn and brake in AS.

I would use my TEST LAMP to verify truck is working first. Then proceed to trailer.

If poor ground, many issues can come up so check that on trailer AND truck.

To properly test circuit for balanced resistance which can affect brightness, use a VOM meter to check ohms and continuity.

Both my truck and my Durango have worked fine in combination with the Airstream through the years. Since both are having the same issue I doubt if it's the tow vehicle. I guess I could check the output at the relay block that goes from the truck to the 7 pin though. I don't see another ground other then the one that comes from the 7 pin white wire and grounds under the couch in the front of the Airstream which is good now. I may try to run a wire all the way from one of the brake lights to the 7 pin to verify if that's the issue, it wouldn't take long. I'm starting to wonder if I have a bad 7 pin connector coming from the Airstream.

[Pacerized]

Originally Posted by idroba

The brake lights and the turn signal lights are the same bulb, same filament. The tow vehicle determines if they will be steady, both sides (brake) or flash (turn). Unless your tow vehicle has separate brake and turn bulbs, if your turn signals work on your trailer, your brake lights should also be operating.

My best guess is some issue with your tow vehicle(s). Seems strange both would act the same though, unless both have different bulbs for brake and turn lights.

There also is some question in my mind about grounding in the trailer lights, and what you are seeing is actually a flashing running light, not the real brake light filament. Are the turn signal lights quite bright compared to the running lights when on? If not, look for a ground issue at the lights.

No, the turn signal lights work but are dimmer then normal while the brake lights give nothing. Any Idea where else to look for a ground issue then the on I've changed in the front of the airstream?

[idroba]

First check the bulbs for corrosion, both the bulb base and the socket itself. See if cleaning them clears the problem up. If not, then attach a wire from the socket metal to a good known ground location, such as the bumper and see if that makes them work.

I am pretty sure that one of those things is going to show up as causing the problem, since the trailer/tv combinations worked last season.

[bonginator]

A few more things. Have you sprayed electrical conduit cleaner on both contacts? Something to try.

Also - they make a diagnostic dongle that you can plug into the 7pin on your truck to test each circuit. This could rule out the truck connections. Don't know if there is a similar dongle for the AS pigtail...

[Pacerized]

I charged an old car battery that I had and clamped on some old multi meter probes to use as a tester. I also used my wiring diagram and my multi meter to test both tow vehicles on the 7 pin socket and both tested fine.
I was able to get everything to light up except for what I thought should be the brake lights from the 7 pin which tells me the issue is in the airstream wiring. I also took off all 6 back light sockets, checked the connections and cleaned each one with radio shack electronics cleaner. This made a huge change in how bright my turn signals, backup, and parking lights were but still no brake lights with either the direct battery feed or the tow vehicle through the 7 pin. I'm now thinking it's not a ground but perhaps either a bad 7 pin plug on the airstream of a broken wire. When I checked the fuses on the 12 volt panel in the airstream I just checked each one with my multi meter. Would the wire from the big 7 pin cord be feeding into that fuse panel? If so does anyone know what color the wire should be that would power the brake lights? If it's not accessible there I thought about opening the big 7 pin cord and trying to give the wire power directly to see if the issue might be the plug or the wire. I get power to both filaments on all 4 1157 bulbs via the parking lights or turn signals but nothing via the brake lights?
I only had 2 hours to give this after work today before daylight ran out but I have more time Wed. and Thursday to figure this out. I'm still hoping to get on the road Thursday afternoon if I can get brake lights working. Any suggestions?

[cwf]

Right now I would say check the wiring from the connector to your AS... not likely 'inside' the AS... but a bad wire between the connector and the AS wiring.

Do you have a place where the wires from the 'umbilical/whip' connect to your AS? I have a box inside, behind the Gaucho marked 'BERG'... maybe you have similar?

[Pacerized]

I worked inside the Airstream last night from the fuse panel. I have a battery under my couch anyway so it was easy. I have 2 fuse boxes, one is original the other I changed when I upgraded my battery and charging system years ago. The original panel has only 5 fuses on it which are fed from the 7 pin umbilical cord. I compared to my owners manual and the color code for what should be the 7 pin that I pulled off the Internet. It goes as follows.
Brown - tested o.k. and powered Right turn
Red - tested o.k. and powered Left turn
Green - tested o.k. powered running lights
Yellow - tested o.k. powered backup lights
Black/red - did nothing when powered by battery
My manual shows that black would be backup lights but also says this would be yellow for Canada???
I'm now thinking that I have a broken hot wire leading from the fuse box to the brake lights due to the fact that the black wire does nothing when powered up.
I have to hit the road on Thursday if there is any way to do this. If I can't find the break in the wire and it looks tough to trace, I think I'd like to just run a wire from the fuse box black wire to the brake lights temporarily. If I did this would I simply run this single wire and branch it off to 4 wires to go to the wire of all 4 1157 bulbs which powers the larger turn/brake filament? At some point I assume the black wire must run into a relay and do this anyway but I can't find it. All the wiring must either run through the walls or inside the belly pan. Do you think this would work for a short term fix until I can do it right?

[wkerfoot]

Pacerized,

The same wires which run the turn signals, run the brake lights. If the turn signals work the wiring is OK. Are you sure that you have power to both wires at the truck plug? When you press on the brake peddle both wires should be hot at the truck plug and therefore into the trailer plug and through the fuses to the brake lights.

Bill

[Pacerized]

Originally Posted by wkerfoot

Pacerized,
The same wires which run the turn signals, run the brake lights. If the turn signals work the wiring is OK. Are you sure that you have power to both wires at the truck plug? When you press on the brake peddle both wires should be hot at the truck plug and therefore into the trailer plug and through the fuses to the brake lights.
Bill

The 7 pin powers correctly when checked with my multi meter and the turn signals work fine when plugged to the tow vehicles. I would doubt if both tow vehicles would suddenly have the same problem at the same time after working fine for the past few years. The 7 pin plug has a specific wire for brake lights. If the turn signal wires are supposed to send power to the same bulb for the brake lights, what would the additional wire be for? I thought the wire coded as yellow on the picture below would be what would send the power from the tow vehicle to to all 4 1157 bulbs when the brake is hit. Am I not understanding how this works?

[wkerfoot]

Pacerized,

The yellow wire is from the brake controller to the electric brakes. The word stop on the brown and red wires means the brake lights.

Bill

Originally Posted by Pacerized

The 7 pin powers correctly when checked with my multi meter and the turn signals work fine when plugged to the tow vehicles. I would doubt if both tow vehicles would suddenly have the same problem at the same time after working fine for the past few years. The 7 pin plug has a specific wire for brake lights. If the turn signal wires are supposed to send power to the same bulb for the brake lights, what would the additional wire be for? I thought the wire coded as yellow on the picture below would be what would send the power from the tow vehicle to to all 4 1157 bulbs when the brake is hit. Am I not understanding how this works?

[Pacerized]

Originally Posted by wkerfoot

Pacerized,

The yellow wire is from the brake controller to the electric brakes. The word stop on the brown and red wires means the brake lights.

Bill

Thanks for clarifying that. I'm now at a loss then. I get power at the 7 pin off the tow vehicles when I hit the brake. I get power from the 7 pin plug on the Airstream to the lights, and I get power from the fuse box to the lights. I'm going to retest from the 7 pin at the Airstream again because it did require a helper to tell me what was lighting up but I checked these myself from the fuse panel.
I still have the black wire from the umbilical going to the fuse panel that seems to do nothing when powered up. Since the yellow is for the backups on my system, do you think the black wire might be going to the brakes?

[Pacerized]

Upon checking the 7 pin plug at the umbilical cord again, I found that I did have some issues afterall. When I check from the fuse panel everything was o.k. I put on a new socket Mon. night but I coudn't open the old socket head to check the wiring. The diagram I posted above wasn't correct and nothing I found online was. I finally checked from the male plug on my truck using the multi meter. Everything seems to be working now. Cleaning the contract on the light sockets was also a big improvement and needed to be done, my lights have never been this bright since I've owned the Airstream.
We're off to the Redwoods Thurs.
Thanks for all the advise.
Charlie

[wkerfoot]

Charlie,

Fantastic, have a great time.

Bill

Originally Posted by Pacerized

Upon checking the 7 pin plug at the umbilical cord again, I found that I did have some issues afterall. When I check from the fuse panel everything was o.k. I put on a new socket Mon. night but I coudn't open the old socket head to check the wiring. The diagram I posted above wasn't correct and nothing I found online was. I finally checked from the male plug on my truck using the multi meter. Everything seems to be working now. Cleaning the contract on the light sockets was also a big improvement and needed to be done, my lights have never been this bright since I've owned the Airstream.
We're off to the Redwoods Thurs.
Thanks for all the advise.
Charlie