wiring problem with LED's

[budepps3760]

Have a problem and hope someone can help me. I installed a 10" LED bar on my tractor about a month ago mounting the bar and running the cable through the body etc. I was not able to finish due to time management however before I left for the day I touched the wires to the battery terminals to make sure I had no bare wire issues and light came on fine with no problems. I disconnected the negative battery terminal so I would not have a dead battery upon my return. Went back today to drill instrument panel for switch and finish running thermal tubing through engine compartment however I could not get the light to operate under any circumstances. The switch has a red, blue and black wire connection. If I remove the blue wire from the 3 prong switch the switch itself will illuminate however the light bar will not come on. With all 3 wires attached to the switch the switch will not illuminate and the bar still will not come on. The switch does not illuminate as brightly it seems as it did a month ago however the tractor cranks right up and runs fine and so it does not appear to be a discharged battery. Any suggestions as to the problem is?

 

[mrmikey]

I'm thinking since it's an illuminated switch the three wires are red+12V from the battery, blue +12V to the light and black - ground for the indicator light. That's just a guess, check it with a multimeter so you don't fry anything.I aaume the light will work if you touch the wires to the battery?.....Mike

 

[Xfaxman]

Does the the light bar come on if you bypass the switch?

Do you have a wiring diagram for the switch?

 

[buickanddeere]

If the LED's don't have reverse polarity protection. They are smoke by now.
Is there a guarantied chassis return/ground connection ALL the way back ?

 

[5030]

If the LED's don't have reverse polarity protection. They are smoke by now.
Is there a guarantied chassis return/ground connection ALL the way back ?

.... and the cheap units don't. LED's being electronically excited are very reverse polarity touchy. Your telling statement is....I touched the wires to the battery terminals to make sure I had no bare wire issues and light came on fine with no problems.

 

[budepps3760]

When touching the red and black wires to the battery terminals only the switch illuminates and not the light bar.

There is a relay in the wiring harness however it is not attached to the chassis, only hanging down currently. There is a metal bar with a screw hole that I can attach to the frame somewhere in case that is a ground however I removed the metal bar from the relay housing because I needed to drill the hole into a larger diameter to accept a larger bolt however the metal bat is not attached to the relay physically. I mean to say that the metal strip slides into a groove on the side of the relay and thus that metal strip does not make electrical contact with the relay itself and thus could not serve as ground for the electrical connection. That is why I held off attaching the relay to the chassis until I need to pull the entire writing harness.

How would I bypass the switch to test the light bar? Just alligator clip 2 wires to the light bar terminals itself? I do not have a wiring diagram (I noticed one imprinted on the relay itself) and of course I did not take a picture of it today when I saw it. I may have to run back to the farm tonight and take a picture of it and post. I was thinking off running by the Indian casino which is half way there and do that would make a good excuse to head that way again.

No ground that I am aware of. However when I tried the lights last time I am not aware of them being grounded at that time either. I am starting to think that maybe that metal strip must be attached to the relay switch and bolted down somewhere.

 

[budepps3760]

Actually it is a Black Oak led. I paid $207.00 for the led and bracket. Anything but cheap.

 

[dickfoster]

If the LED's don't have reverse polarity protection. They are smoke by now.
Is there a guarantied chassis return/ground connection ALL the way back ?

Just so you know. LEDs are diodes so they have their own inherent reverse polarity protection built in. Diodes only allow current to flow in one direction so if you hook them up backwards they just don't work but no current flows so no damage. To cook them you have to exceed the voltage rating and allow too much current to flow, then they will live for only one brief shining moment and shine no more.

 

[5030]

But.... It's the circuitry associated with the LED's that is polarity sensative.

 

[5030]

Actually it is a Black Oak led. I paid $207.00 for the led and bracket. Anything but cheap.

Thats not all that much. I run CREE 9 high output LED lights forward facing on both my tractors and they were each 150 per lamp. 300 for the front, 300 for the rear times 2 units.