# Troubleshooting electrical issue



## jstmarie (Dec 4, 2018)

I've got a fisher homesteader plow I've used for 5 or 6 years now. It is mounted to my '98 Jeep TJ which is now a "yard truck" (I only plow my own driveway). I've had intermittent issues where the plow would not respond to the controls but I've always been able to get it working again by fiddling with connections etc. 
Currently the plow will not respond to the controller. I turn the controller on and the red LED lights up but when I actuate the controller (up, down, left, or right) the light turns off. I get no click or response whatsoever. 
I pulled the solenoid and tested it electrically, which was fine. I then energized it and got a click and continuity across the two "power" posts. I checked all fuses (2 10 amp and the 15 and 7.5 amp fuses) and all checked out. I removed both battery terminals and cleaned them up (like to check the basics) and I did the same for the positive and negative terminals on the plow motor. 
After all this I noticed when manipulating the 11 pin connector between vehicle harness and plow that the 3 port control module would "click". This was very repeatable. I narrowed it down to the connectors themselves, pretty corroded inside, so I cut them off and wired them up manually with tube connectors for now. This got rid of the module clicking but still no response from the controller except the LED turning off of course. 

I tested the plow motor itself by connecting it directly to the battery and the motor spins. I ran a lead from the positive battery terminal to the solenoid and the motor spins as well. I'm not sure what I should do next to diagnose and I sure could use some suggestions. 

Much obliged,
Jon


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## Randall Ave (Oct 29, 2014)

There's a thread here to diagnose your issue. Sounds like a voltage drop. Clean the battery connections.


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## Western1 (Dec 4, 2008)

Thinking you have a bad power cable either plow side or truck side. Use your jumper cables to figure out if that’s it.


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## Mr.Markus (Jan 7, 2010)

I agree probably wasn't the pins but a bad wire in between...symptoms could be either ground or positive


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## cwren2472 (Aug 15, 2014)

https://www.plowsite.com/threads/6-pin-fish-stick-keeps-turning-off-when-pressed.175132/

Spoiler alert: it was a battery cable.


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## jstmarie (Dec 4, 2018)

Thanks for all the replies, the link to the other thread was helpful as well. It does indeed behave like a bad ground or power cable. I'll test each when I'm back home tonight.


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## jstmarie (Dec 4, 2018)

When I finally found time to put some focus on this I started with testing the positive side by connecting my jumpers from the positive battery terminal to the "hot" side of the solenoid; no difference. I did the same on the negative side by connecting the negative battery terminal to the ground on the plow motor; no difference. I then began to check voltages and continuity of grounds. I tested the red/yellow wire (pin 1) of the control connector (the harness that comes through the firewall to the controller with the red wire tapped to the fuse box).










I had around 10 volts here. This raised a red flag, I should have battery voltage here. I re-checked the battery voltage and I had a bit over 13.5 volts. I also confirmed I had continuity to ground (pin 3 orange/black).

I wanted to eliminate the isolation module as a possibility and had read elsewhere on this site that you could jump the red/white wire with the red/yellow wire to do this. After a while I found the place to do this (see schematic below for location). It turned out not to be necessary.

I then set my multi-meter up at the 7.5 amp fuse so I could monitor the voltage as I walked through the harness wiggling and jiggling until I saw a response from the meter. Once I found the general area I had to cut the loom in a few places to track down the exact location of the faulty wiring.










The red/green wire runs to two red/black wires via what looked like a heavy duty butt connector and this was corroded.










I cut out the corrosion, soldered the wires together, and we were back in business.


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## Western1 (Dec 4, 2008)

Sweet!!! Good luck!!!


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## TLB (Jan 19, 2007)

dam corrosion.


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## Mr.Markus (Jan 7, 2010)

TLB said:


> dam corrosion.


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## FredG (Oct 15, 2012)

Mr.Markus said:


> I agree probably wasn't the pins but a bad wire in between...symptoms could be either ground or positive


 I was on the side of the road yesterday, No jagoff light. Went back to the shop and got the test light out. As most of the time for me it's the darn ground. Whoever wired it grounded it to the cargo light screw and come loose.


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## jstmarie (Dec 4, 2018)

That was under the original harness loom, so I'm guessing that's the way it came from the factory. Wouldn't surprise me if that point commonly fails.


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