Dim taillights on the fiver

[Radshooter]

The taillights, turn signal lights and brake lights on the back of our fiver are getting pretty dim. Need a poor-mans fix if any of you have any ideas. Eventually I would like to convert them to LEDs, but unfortunately, that is not in our budget right now.

My plan is to remove the lenses, clean them on the inside thoroughly, try to clean the bulb receptacle with sandpaper or something like that for better contact, and put in new bulbs, even though the ones there still work.

Any other ideas are extremely welcome.

Thanks for your help... ... . Steve

 

[jelag]

If all the lights are dim, I can only assume that you have a poor ground..... any single connection that is loose, has rust under it... . will not allow the current to flow correctly...

What I'd try is to wire brush a spot on the frame of the truck and the frame on the trailer... . I'd put a jumper cable between the two frames... if this fixes the problem its a ground between the trailer and truck... look at all those connections... .

If this doesn't take care of it... it could be a common ground wire strung through the trailer light to light and it has one common connection to the frame of the trailer... . and than this connection could be the problem...

I'm in the pacific northwest where a lot of chemicals are used on the road... these get into the connections and give us fits...

We've opened the connections on the back of our trucks and trailers and used a non insulated butt connector and than use a shrink tube that has adhesive that melts when you shrink the tube...

There is a common connector on the back of the truck where the trailer plug ties into the factory wiring harness... and breaks out to the 4 pin connector. . this plug has been a real problem and we've hard wired and taken it out of the circuit in the method mentioned above...

My 5er has a metal junction box where the wiring harness and cable comes from the back of the truck and connects to the trailer... this box is not water proof and the connectors are wire nuts... . this connection has been a problem for use as well. . I've installed a waterproof box and have coated all the connections in a sealer to prevent this problem...

Hope this helps. .

 

[Radshooter]

Thanks jelag... . Our frame is completely enclosed by an underbelly. I would have to drop the belly pan to get to it. Could I ground from the truck to the pinbox? Would that do the same purpose? The pinbox is the only part of the frame exposed.

If it helps, all the lights on the back of the trailer are the same brightness, just very dim. That makes me think it is a common problem instead of just one housing or the other.

Thanks again..... Steve

 

[Slow Six]

I tend to agree that it is a ground problem. Could the problem be in the seven pin connector, truck or trailer end ?

 

[steved]

Check your voltage at the tail lights to ensure it is a ground problem before you start chasing something down that isn't the problem... but it definitely sounds like a ground problem...

See what you have for voltage at one of the tail lights... if it isn't the same as what you have at the battery, you got a grounding problem as the others have already noted...

steved

 

[jelag]

The pin box will work to test from... .



BUT steved has a point... if there is dirt, rust, or bad connection in the tail light circuit it can cause dim lights... that is the hot wire in the connector, not the ground... .



HOWEVER if the dim lights include the stop turn signals than the problem has to be a bad ground... . or bad connectons on all circuits, tail, LT, RT, etc...

 

[Matt42]

Dim trailer lights can also be caused by a fine to thick coating of dust on the bulb and reflector. Sanding the reflector and painting it white can also increase reflectivity, and thus evident brightness.