I have been trying to build a unit that tests the lights on semi or car trailers. In a nutshell, I want to be able to cycle between a series of outputs (lights) and possibly drive it with some sort of remote.
I have bought a uno r3 starter kit, 8 way relay board and a remote but I have no idea where to start. I am trying to learn but its hard going!!
Does anyone have a link to a success story that has the code and / or circuit please? I have tried to find something but lot of the threads just seem to die without anyone reporting back how they got on. I have found a couple threads that seem to have the code I need but it may as well be written in Hindu for all the ability i have to understand it!!
Do You intend to connect to regular electric plug of the trailer?
I suggest a sketch that cyclically exercise the trailer. However You need 24 volt some way.
That's a fairly broad requirement.
For example, as noted already, there are 12v and 24v systems.
Semi's would have more light load than a car trailer.
The use of incandescent and LED bulbs would also need to be taken into account.
Not really sure just what you intend to "test" so you might have to be more specific.
I imagine it will all depend on how the rig is wired, but this sort of thing has been done before with a differential relay. This would have to be pretty sensitive for the scale you are proposing, but a modern electronic version may be up for that.
Test the lights or run them?
How about a 3x5 display that shows which lights are actually on so you touch the brakes and see lights on the display drawing? Make the display colors same as the lights. Light detectors are cheap and tiny.
Such a thing can run on 5V. With 2 controllers, one in the back and one in the display, serial or I2C could work with 1, 2 or 3 strands of wire in between.
Thanks for all the quick replies. Much more than I expected
By ‘Test’ I mean cycle through them to see if they’re working and have the option to apply steady voltage to one or more pins for diagnostic/ wiring purposes.
If it cycles the lights then it means I don’t have to keep walking up and down the trailer to switch the various lights.
It will be mounted in my service truck and run from my 12v leisure battery. The 12v side is simple. For the 24v side I’ve got a 20A 12>24 voltage converter which should do the job. I’ve had a bit of success using these before.
Thinking outside the box, and splitting the problem up, I’ve had some success with a basic code running 3 relays in the bank of 8 I have where relay 1 is on for 1 sec, then off. Relay2 on for 1 sec then off etc etc. I could do all 8 I think but I ran out of jumper cables however, I wrote code and made a thing!
As there doesn’t seem to be a single source of code and the hardware side anywhere online (that I can find….) my intent is to do that on this thread in the hope it may assist someone else
I was writing about detect the light to be sure it works and you can watch confirmation from the cab at any time. Use bluetooth and a phone app, there's your display. You do run the lights from the cab with regular light controls?
That’s the problem. I fix them (as well as other stuff) for a living and sometimes I don’t have a tractor unit to plug into. The trailer gets dropped off at the workshop and I repair it or whatever.
I’ve googled Arduino trailer light tester but I don’t know how to ‘read’ the code to make a project that the code will run, if that makes sense??
I am hoping to make this project work and then put all the info here, as there’s bound to be someone else like me that hasn’t really done arduino before
So you will supervise the switching of the lights outputs?
One does not necessarily require a uC to do the job however it is easy enough with arduino and interface/buffer transistors.
Simply turn on Arduino outputs one at a time with a delay in between.
With the right choice of components I can see where the voltage difference between auto and truck would present no problem.
Should be easy enough even for a raw beginner.
In that case, ignore my previous. I thought you wanted to check your own rig while on the road.
I'm guessing the first thing you will need to know is how many lights are installed on the trailer, which likely means walking around and counting them. In that event, you might as well do it with the power connected.
however, I wrote code and made a thing!
