Company has a 2016 Freightliner. Tandem, setback front axle. Gravel truck. Not sure what you call it, popular as an oil tank truck. It moves my compact grader around on a tag along float. Not the driver tharth why I am short on details. Mentioned to the driver that he has no driver's side brake light on the trailer. He switched trailers so they, our shop, could do a brake job. Noticed the same problem on other trailer. Everythi else works but that brake light. Mechanic looked at it and couldn't find the problem. Have to send it to Freightliner. In my day, the plug had one wire for brakes, and one for each signal. Both signals are fine. That light works with another truck. Thoughts
When hooked to this truck one brake light doesn't work and the other one does, but on another truck both work? Assuming this is an air brake trailer I'm stumped.
Could it be someone improperly wired brakes from turns?
I can't figure out the mechanics of it. One source of fire at the plug only powers one light, but switch trucks and all is fine. Only thing that comes to my mind is a poor ground situation, but not sure why it's always the same light on every trailer
I'm thinking some Yahoo wired his trailer wrong. Should be wired like this. Hell, the plug even says what color goes in what cavity.
Has to be in the truck. Does the same thing on all 3 trailers, all different makes, but they work fine on other trucks. Plus it worked fine last year. Trailer sits all winter, and the truck hauls snow. I'm gonna have to pull the plug apart myself. Hate to step on the guys in the shops toes, but I need to get my mind around it
I would check relays. Freightliner really loves relays. After you check the chord receiver of course.
This is confusing... Most trailers have four lights on the rear, the two inner lights get power from the red wire in a 7 wire system. the outer lights are turn signals, Yellow/left, green/right. Is your truck wired so the turn signals act as stop lights too unless the turn signal is on? If so, the turn signal switch may be bad. Or... worse, being a 2015, it may have an electronic module that runs the signal lights. Ran into that one on a Peterbilt a few years back, The owner wanted his 4 way flashers independent of the brake lights. The dealer had to reprogram it.
The more they over take the plumbing, the easier it is to stop up the drain
What model of Freightliner is it? And last six digits of the Vin Number please. Truck Shop
I'm no where near it till Monday. I'm not the driver, he's my float man. If you Google Freightliner gravel truck, it pops up. Set back front axle, it has the dashboard of a Sterling. See what I can find out Monday.
2016 M2 106. HM5573
Ouch... M2 many modules. I'm out on this one. Tried to troubleshoot an A/C control issue in a 2010 M2, No charge to the customer and sent him to Freigtliner. within 15 minutes they had plugged in and found the problem component (some ridiculous sensor) And down the road he went.
About as bad as ABS power supplies. My current ride powers up the module on stop(amber lamp momentarily flashes with brake apply), does have power in Aux 7 way plug terminal with key, other wagon owner has the aux terminal is always hot and the module never powers down, lamp only flashes when plug trailer in. All too many variations on theme in the real world, DOT enjoys playing tag and ticket with these variations.