I have a 2005 CAT D6N LGP. The machine started and went into reverse but when I put it in forward it would not move at all. All the lights on dash were flashing. We found a blown trans fuse (15 amp) and replaced it but going through the same procedure it blew again.
As it's an electrical problem the first thing that will be needed is the machine Serial Number in order to locate the correct electrical schematic.
ALY01471
OK, got the right one. There are 3 different ones for ALY depending on S/N so it's good that you gave the full one and not just the prefix. So if I understand you correctly if you select reverse in the transmission it works fine in any of the three speeds but if you select any forward speed it blows the power train electronics fuse #14.? At the back of the machine is the 15-pin harness connector (1) for the transmission. Disconnect it and try the transmission in forward speeds again. I know the transmission will not engage, I'm just interested to know if it still blows the fuse.
Not sure about all three speeds. I had a mechanic that determined it was the fuse. We assumed we had the problem solved. I put it in reverse 1 to line up the final drive to drain. After going to far I put in forward and it blew fuse again. The mechanic may be 2 weeks out getting back which is why I’m trying to fix myself.
I will locate the harness this afternoon and get back Thank you for your help
Update. Mechanic was able to make it out today unexpectedly. We narrowed the short down to the parking brake switch. Install new switch soon. Hopefully that solves the problem. Thank you for your help.
It seems strange to me that a shorted switch would cause the fuse to blow only in one direction and not the other. Please give some feedback if the replacement switch fixes the problem.