JD5205 blowing head light fuse

[deere5205]

I have a 2000 Deere 5205 4WD and FEL with about 1200 hours on it. I having trouble with it blowing the fuse for the head lights and the fuse for the flashers. When I replace the fuses the lights and the flashers will work fine, but after a few hours of daytime usage I tried the lights and flashers and found that the fuse had blown again. I've been through this twice now. I've spent and hour or so looking for a pinched wiring harness but have found nothing so far. Looks like this is going to be a challenge to find the problem. Anyone ever seen this? Or know of a particular area for me to look at?

Thanks
Larry

 

[Willl]

I've had the light bulb itself cause fuses to blow, so don't rule that out.

Easy enough to test by just unplugging right at the bulb(s).

 

[deere5205]

I finally got time to find the problem so I thought I'd report what I found incase it can help someone else out. I removed the blown flasher fuse and connected the fuse terminals with my ampmeter so I could momentarily flip the flashers on and see how much current was being drawn. With a schematic in hand I proceeded to unplug parts of the wiring under the dashboard. The flasher circuit is connected to diode packs under the dash. I removed them and tested them with an ohmmeter. I was getting intermittent readings with my ohmmeter and the cover was easy to pop of so I removed it and was able to see cracked solder joints inside. I attached a photo of the diode pack with cover removed. The arrow is pointing to where the solder was cracked along the edge of the little circuit board. This was not the cause if my fuse blowing problem, but I resoldered it anyways. I figure I'm fixing another intermittent problem before I notice the symtoms. Both diode packs under the dash had broken solder joints.

Back to finding my short... I unplugged everything I could under the dash and I removed all the light bulbs in the flashers and found that the wiring going to the lights was still shorted. Examing the wiring, I discovered that the wire had worn through the metal piece that holds the light socket. The wire had no slack and that caused it to be tight against the metal. I found the same problem on both flashers. My fix was to cut the wire, solder in a 3" piece of wire with a plastic tube over the wire so it would no longer rub against the metal. The attached picture shows the location of the short. These are the yellow flashers that are mounted on the roll bar.

 

[Zebrafive]

Thanks for the update. For those who do not have an amp meter, a light can be rigged up in place of a fuse, so you can find a short.