# Boss plow blowing headlight fuses



## jonc41 (Nov 28, 2016)

Hey guys, have a 9.2 Boss V plow, blows low beam fuses right away-obviously a dead short. Have isolated the problem to be in the plow wiring, not the truck side. Started looking for the short, have 0 ohms full continuity from low beam power to light ground at the 13 pin connector. Whole plow harness looks good in full loom no rub marks anywhere. Unplugged the left side low beam bulb, and my short went away. Now I have continuity between the high beam power and the headlight ground pins. Not blowing low beam fuses anymore but the low beams both don't work could be bad bulbs as they have never worked since I got this plow at the beginning of last year. If I unplug both high beam bulbs the short in the high beam system goes away. As soon as I plug one bulb in the short is back. Doesn't make sense to me how the short has moved from low beams to high beams. Anyone had this happen before? Is there a spot inside the light assemblies that's known to go bad? Thanks.


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## dieselss (Jan 3, 2008)

Your only checking the harness itself.
Need to ck it to ground


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## jonc41 (Nov 28, 2016)

That makes sense. Very stupid of me. I have found at least one low beam bulb is blown, getting a new pair of them now. Stopped blowing fuses after I unplugged tgat bulb and plugged it back in again. Chances of the bulb causing a short is pretty slim I will double check everything once I get back


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## RyKR (Dec 9, 2018)

I just bought a pickup that has a BOSS plow on it. It was also blowing low beam fuses. It is a 2004 Chevy truck with a fuse for each of the 4 headlights. I found that if I pull the rt. high and rt. low beam fuses the lights work perfectly. If I pull the dr. high and low beam fuses the lights will have high and low beams, but they are backwards. The highs are on when they should be dims, and vice versa. Not sure what it points too. I'm guessing that the harness was not an exact match for my truck.


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## jonc41 (Nov 28, 2016)

Ended up putting two new low beam bulbs in it and they are both working and no longer blowing fuses. Kind of strange but we will see where it goes from there.


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## jonc41 (Nov 28, 2016)

RyKR said:


> I just bought a pickup that has a BOSS plow on it. It was also blowing low beam fuses. It is a 2004 Chevy truck with a fuse for each of the 4 headlights. I found that if I pull the rt. high and rt. low beam fuses the lights work perfectly. If I pull the dr. high and low beam fuses the lights will have high and low beams, but they are backwards. The highs are on when they should be dims, and vice versa. Not sure what it points too. I'm guessing that the harness was not an exact match for my truck.


I have seen something in my search for my own problem that if you have a 5 relay harness on those trucks it may not work properly and require a modification to the harness possibly. Removing the 5th fuse may even solve your problem


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## Randall Ave (Oct 29, 2014)

jonc41 said:


> Ended up putting two new low beam bulbs in it and they are both working and no longer blowing fuses. Kind of strange but we will see where it goes from there.


One time I chased a short for hours. Short was in a bulb. You would think the internal wire would melt. But no I guess.


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## zlssefi (Dec 29, 2011)

sometimes the filament blows then makes contact with the bulb base, hence making a short and will blow fuses till the bulbs are replaced. modern day plow harnesses are very reliable. Im not saying they are perfect because i have seen issues in the molded harnesses, but overall they are very good.


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