Lots of factory lamp switches are high current DC rated, so they run the power through the switch instead of using a relay and a low current, probably AC-only rated, switch.

There are a lot of reasons why the OEM and the aftermarket do it differently, but the short answer is cost and liability. It's relatively inexpensive for the OEM and relatively expensive for the aftermarket to use a high current DC switch.

Very few switches are rated for both AC and DC, and lots of people assume an AC rated switch is good for high DC current, but that's not true generally. Whatever current a switch is tested to handle will be marked directly on it if it's not OEM (the OEM may only have a part # since there's no liability for substitutions by individuals ... it's a direct replacement part only). If there is no DC rating marked on the switch it won't handle much DC current. Even if it is both AC and DC rated, the DC rating will usually be much less in Amps.

A switch marked 10A 120V AC may only be good for 1/20th the DC current ... 500mA @ 12V. The reason is partly due to contact construction but mostly it's because AC has zero volts across the terminals 60 times a second, and that serves to stop an arc across the terminals. DC is "always on" so you can't rely on the power going to zero to stop an arc.

So DC switches have a much more difficult job and tend to cost quite a bit more; that's why the aftermarket doesn't use them and uses relays instead. The OEM, being in the business of designing and installing parts for 12V DC might have a suitable part just sitting there in the bin at relatively low cost.

The switch itself could be failing, have corroded or pitted contacts, or poor connections somewhere in the circuit; could be hot (+) side or ground side.

Chances are the lamps are grounded near the housing somewhere, that would be a good place to check for bad grounds or loose connections.

Examine the switch if you can for signs of heat or corrosion, loose contacts, etc. If you have a wiring diagram you can examine it and see if there are other connection points that might get loose, corroded, etc. and try to address them.

If the switch is bad, it's probably cheaper for you to go the same route the aftermarket does ... rewire the circuit to accept a relay. But the junkyard is always an option.

There should be only about 200 mA at most going through a switch connected to a relay, so it shouldn't get hot really. A DC rated switch controlling a lamp however will have all the current the lamps use going through it ... plenty of current to generate heat.

You shouldn't leave it that way; heat has a way of degenerating into sparks or fire. It's all relative ... a little heat might be normal, it might not. Maybe someone who has the same lamps/year truck/switch can chime in about that.

 

hmm sounds like i have a couple of options to think about?

 

I kind of wanted to update some folks. Went to my grandpas store today and was walking around pricing a few things, by the way this is store is completly electronic stuff and i dont mean tv's and computers and that sort. But my grandpa walks in from the back, we chat for a few, mext thing i know he is taking me to this big spool of 12guage wire and he asked me how much i want. Me not wanting to be greedy I tell him 5ft will do. he looks at me and laughs how about 10ft i say yeah that should do some of it lol next thing i know he pulls out 15ft and asked me again will that work. I said yeah.... He says how many more lights you have left to hook up, so i say any where between 9-11. he laughs and pulls out 20ft of red and black 12guage wire for me then he walked over to the relays and pulls out 5 and hands them to me. (im not sure if this is the correct word on what exactly they are) but he gives me 5 sleeve type things that you connect your wires to and it plugs into the relay. I fell horrible taking all this so i ask him how much for all of this he laughs and tells me to have fun and he hea towards the back room. I just wanted to give my grandpa credit. He helps me out as best as he can I really appreciate, every bit of help that man has gave me over the years. i also want to thank everybody here at dodgeforum. not only in the short time that i have been here, have I got help for everything I ask. But I get on here almost everyday. I dont always post things, but I have learned tons, and will continue learning from everybody here. So thank you everyone!

 

nice hook up there

 

So you have already noticed.....we grandpas are pretty good to have around.

Here is an idea......go see if granpa will help you hook it all up!

Tell him you want to make sure it is right. I'll bet he will be more than happy to do it. It will make him feel appreciated and help you learn at the same time!

 

that was my original plan a few months ago was to have him walk me through on how to wire all this up. honestly every wiring diagram i could follow to a point then get confused on. then one morning I woke up and said its getting done today and it did. It felt great. I have helped him remodel a few rooms of his house and his shop and garage. But I told him this summer if he has any work to do give me a call. I hate just taking things so I told him since he wont take my money, I will at least work my butt off to pay him back. I'm just not like my other cousins and take advantage of him.

some nights I go onto the second gen ram forum and start from the last page and work my way towards page 1 just because their is so much to learn, yeah a lot of stuff is the same just posted multiple times. From what I have learned here it makes me confidant enough to tackle my own problems on my truck.

I appreciate every body's imput on this site

 

I like it when my grandsons want to watch and learn. I usually put them to work on tasks they can accomplish so they can feel good and help out. I will probably give the oldest one of my sevearl project cars when he gets older because I know he will work on it and learn and be appreciative. It makes both of us feel good!

And granpas ususally are not worried about money. They want to be involved and help out.

 

That is exactly what I try and do with my grandpa. I'm very respectful towards him. I hope one day I will know half the stuff that he knows.

I know he is not worried about money, he is not rich by any means but he is smart. He enjoys helping and i know he also enjoys that I'm interested in the stuff he is. I still just don't like taking stuff because I know he will pay for it or whatever the case may be. I'm just not the type of person to take things. But I completely appreciate it, and I look forward to more projects with him this summer

 

And because you are like that, I would bet that when you are walking away, with a smile on your face, HE also has a BIG smile on his, knowing that you actually appreciate what he does.

 

I have these buyers brand led lights on all 3 of my trucks and love them, they are real bright and reasonably priced.




http://www.globalindustrial.com/g/ja...Utility-Lights