Hey all. Been a while since I have been on here.
First, I am not that great at wiring issues so thought I would come here to pick some brains.
So, this is what happened and this is the second time it happened. I know I probably shouldnt have, but I put a meyers 7 1/2ft plow on my 2001 Dodge Ram 1500 Quad. It has been on there for about 6 years. It has really held up well over the years as I try and take it easy on the truck. I will not push any wet snow with it.
Anyway, about 5 years ago, the plow light relays that is installed with the meyer lights (2 of them) burnt up. I took it to the dealer and they fixed it for about $150 and disconnected the meyer lights. About 2 years ago I decided to have them hooked back up with new relays. It was done by a shop that works on Meyer Plows. It worked great for about half the season and then again, the same thing happened.
I don't know if it is all related but sure seems to be. When the relays burnt out, it screwed some stuff up on the truck. First, driver side headlight is dim while the other side is normal. If I put the hi beams on, the driver side gets very bright and the only way I can get the drivers side to go back to low beam is turn lights completely off and back on again. Also, sometimes out of the blue the transmission will go over 3000 rpm before it will shift gears, its an automatic. But, if I pull over, shut the engine off for about 10 seconds and then start back up, everything goes back to normal. It also on very rare occasions, when gas guage gets to 1/4 tank or below, it can go to dead E on the guage.
Does anyone have any idea what this could be. I never looked at the reciept from dealer to see what they did when this happened the first time so dont know what it could be. It does not throw any codes when I put the switch on 3 times on and off. I did show one code a while back but it was the vapor leak from when an idiot at the gas station broke my gas cap.
Any thoughts would be appreciated.

 

electrical gremlins. Such fun. Check the wiring at the back of the headlight switch.

 

Already did that and everything is fine. I am wondering if there is somekind of relay or something that would be causing it. But I would have no idea how to search it out. I guess I am probably going to be visiting the dealer again.

 

Do you have daytime running lights on your truck?

 

I had the same problem with the driver side HL. A few weeks back, I went out to plow and could not see shat. The other day I got annoyed and pushed and pulled the Hi beam (multi function switch) on and off about a hundred times(I was pissed). But it works again. So I suspect the multi function switch has bad contacts inside. I have a Fisher "two hour mount" LOL but I'm not blowing any relays. You should check the multi function switch and the wires running down the steering column.


For the tranny issue, sounds like a clogged Governor Solenoid to me.

 

What does your voltmeter say when it's acting up? One way you can rule in/out the plow electrics is pull all the related relays. If the problem goes away for good, something plow related...if no change then it's not related.

 

My problem was with or without the plow hooked up. And it effected what the plow lights did. Of course like I said, I don't have the relay problem like the OP.

 

That's the fun part. Each piece of info about what affects what is a clue. In the right hands a good multimeter can be used troubleshoot almost anything. It's usually a matter of running the right tests and piecing together the evidence.

 

Okay, I am about to get long winded here. Things to keep in mind - the voltage regulator is built into the control module. Whatever connections to the plow are there, are not so great. I think some poor connections were made & not entirely weather proofed from the shop. Moisture got into them & caused un-regulated voltage surges which may have been enabled further if the shop hard wired without fuses, or much larger fuses to get your truck out the door asap. If a surge was regular after the poor repair, it could have damaged the voltage regulator for starters. Other connections that are known to be weak in the gen2's were also likely pushed over the edge. The poor thin wires in the column, the headlight switch, the connections at the headlights etc. If you discover the voltage is not regulated correctly, you will need to replace the ECM, but I would advise getting an externally mounted voltage regulator which is what the gen1's had. There is a company that makes a great kit for this. That would be my first step, then look for corroded connections on both battery cables at both ends, then alternator connections. If the shop had any of the various connections disconnected, as in the multi terminal molex connections, they could have 1 damaged wire or not be connected correctly or even have moisture in them so look for corrosion in them if you disconnect them and look carefully. If the ECM is damaged in a way that causes all this, it may not read codes due to the damage. Do not throw $$$$$ for parts & guesses at this. Get a diagnostic either with your multimeter or from a better shop to see if the voltage is steady. Only after proving it is wrong would you need to look into another ECM. If & when you find spots for your plow or plow lights that have wires running thru something, or out of something, make sure they are not running over or thru a bare sheer metal surface, they need rubber eyelets to protect them. If the places where wires are outside of your truck have enough room for simple air to move through, like a plow light, you can close then with silicone (permanent & a pain to remove) or bee's wax (think snow seal for your boots). I am 1 of those weird people that loves electrical work as long as I am not in the rain or cold. I know most people think a dealership is THEE place to take it, but it is not. Look up an auto electrical specialist in your area also. I have ALWAYS had better luck using an independent electrical shop when it was above me, then I ever did at a dealership. I hope this helps.