Have you delved into the owner's manual for your mower? In the manual, the Protection Loop (part 141940) seems to be indicated as an "either/or" type item in the hour meter circuit. So, it may be that either the tractor has an hour meter, or it has the Protection Loop. I see no correlation at all between the Protection loop and the ammeter. Does the fuse blow when the key switch is in both operating positions (RUN + LIGHTS and RUN - NO LIGHT)? This problem you describe (suddenly blowing fuses) has appeared in the forum in the past, but if I recall correctly, there were reasons other than a protection loop component involved in those failures. Watching the video you linked to made smile when the guy walked from the Kohler powered tractor over to the Briggs powered tractor and pointed to "a diode" used on that tractor. The diode he pointed out on the Briggs is the OEM Briggs rectifying diode for the Briggs 3 amp charging system, no relation to anything regarding a protection loop. And looking at the owner's manual for your tractor, I see that it has the Kohler 15 amp alternator charging system. I then referred to the Kohler service manual and the 15 amp system used on CV 16's has a combo rectifier/voltage regulator instead of having any separate diodes, or in other words.......the diodes are "built into" the regulator module. So, if I was trying to find the culprit, I would be checking out the key switch first to determine if it had suffered an internal failure that is allowing the Battery Positive feed circuit to short to ground inside the switch. The key switch is comprised of both battery hot circuits and is also equipped with a grounding circuit. I have seen numerous cases of key switches failing internally with the symptoms you report. If it was me doing the testing, I would pull the multi wire connector loose from the key switch and use a jumper wire to jump from the battery hot terminal (RED wire that is hot) in the connector (marked B on the switch) over to terminal A1 in the connector. Making that jump duplicates the action of turning the key to the run position. If you are able to jump between the B wire and the A1 wire without the fuse blowing......replace the key switch. This post was edited by mownie on Wed, May 14, 14 at 11:56

They run main power cables up the trunk to distribute power out to the various levels of the tree. Most of the light strings say no more than three plugged end to end. Inside the plug part are tiny fuses to protect against overload. There are usually extra fuses packed with the new strings of lights.

Has anyone run into this problem? My board keeps blowing the 3 amp fuse on the main board and I'm not sure why it would do that. I can't find anything about it on the web or in the books.

In a car, it's pretty obvious because other fuses are there with less ambiguous values. By the way, the colors are meaningless. While manufacturers will make different valued fuses in different colors, there's no standard for this.