thomas.smith598

Hello all, my 2500 HD left turn signal out of the wiring harness shows no power when I test it with a test light. I followed it all the way up to the motor with no current on it. My fuses are good...I have power on everything else but the left turn. Have you heard of this being a common problem? I couldnt find anything on here relating to my problem. Also, is that silver box mounted to the fender side of the fuse block on the drivers side the PCM? Could that be a possibility? Thank you so much. This is driving me crazy!!

SOhappy

Very common. If it's not fuses then it could be a bad relay in the IPM (darn near impossible to replace) or a bad circuit in the "silver box" or FCM (that's what was wrong with mine). Either are expen$ive to replace. So I went with the Modulite, a ~$60 fix that will solve the wiring issues for good.

See link: https://www.dieseltruckresource.com/...light=modulite

sr4440

save the headache, put a modulite on it and forget it. that the way it should have been done from the factory.


Joe

thomas.smith598

Thank you both for your replies. I was sweating having to take this thing out and spend bookoo bucks on this silly little small box wrapped in alluminium. Can you tell me what part # on DrawTite it is? I am having trouble finding which application is for my 03 2500 HD. Thanks a ton!!

sr4440

get the 119190 plus the wiring kit 118151 so you have the wiring harness.

FYI https://www.dieseltruckresource.com/...d-t242893.html

Joe

thomas.smith598

Thank you very much, I just ordered it. Now I only have to hope it cures the problem and it isnt too difficult to install. I was reading I should only hook up certain wires and not all of them. I also read that I should remove some fuses...I need to reread those posts to make sure I do it correctly...Thanks again.

sr4440

one thing, on some dodges they also have a 4 pin trailer connector located under the bumper. if you do, connect the modulite wires before it, so you will have both the 4 and 7 pin trailer connectors working when you are done.
you can pull the fuses or just tape up the cut wires under the truck.

Joe

thomas.smith598

i do actually have the 4 PIN under there so that is good to know. What fuses should I pull? Just the left turn/stop or all the trailer fuses on the block? I guess that depends on what wires I hook up right? Should I just splice into the left turn since that is all thats givivng me problems or just do them all?

sr4440

well, i not a big fan of a "mixed" system. you might give the next owner fits. I would pull all the lights off of the tail lights, but it would work either way.

Joe

El Borrego

I have an '03 HD 5.9 dually. Two years after I purchased it I hooked up to my Fiver to relocate from TX to LA. Left trailer lights would not work. Stopped at 2 RV shops to check trailer out and both said it's not the trailer, it's the truck harness. Sure enough, they were right. It was out of warranty. The Dodge dealer where I purchased it located the problem and then I went into shock. It was the fuse buss block under the hood, that part of the buss was shorted out (came from the factory as this was the first time I used plugged into it). At the cost of $800 for the buss plus labor I was repaired. I asked about using a spare on the buss and relocating the wire. Dealer said they couldn't do it as the computer knew what was supposed to be where and how much load was to be on that fuse. Didn't make sense to me but since I didn't want to blow a computer with a short, I left that theory alone. Good luck on your issue and hope your fix is near painless.

thomas.smith598

Well i did finally finish hooking up the wiring and to date it is working accordingly. Now i just have to get my old piece of junk trailer up to date. Thank you everyone who has assisted in this operation!! Happy trails!