Moving this from another thread- hope it helps someone-
Bought this in early 2020 with 1100-odd hours - ran fine until a month ago when DFI light came on and mule had zero power. Sounds like it's idling just fine but in truth it's idling on one cylinder, the front one.
I can't get the DealerMode to throw any blinks from the DFI light to diagnose, I cleaned the not-so-dirty battery terminals till they were copper-shiny and did make a bit of difference, the DFI light was off for a short time but now it's back on steady after startup. Spark tester in between sparkplug and sparkplug lead shows good fire on front coil but none on rear. I had the plug out and laying on metal to look for spark when running and I saw a single spark. Can't find any documentation as to whether ECU disables the fuel injection when something's out of whack and DFI light on, or if it disables spark, or if DFI light is on because of failed rear coil.
So I decided to try to extract the rear coil-
The rear coil is of course notoriously hard to get to; the service manual says to remove the starter- but get to it I did, with no starter removal - you have to unplug the leads, then using an 8mm box-end wrench, you can loosen the driver-side mounting bolt -the harder of the two to get to - I was then barely able to get my index and social fingers in there to loosen most of the rest of the way, and then finished the job of removal with some long-reach needle nose pliers once I could get on the threads of the bolt. The passenger side is easier because there's more room. I loosened that bolt with a ratchet then was able to get my thumb and finger on it for removal.
Testing the coil windings for resistance shows the following:
Primary reads 0.9 ohms wherein the manual lists acceptable readings of 1.9 to 2.5 ohms
Secondary reads 18.85k ohms, the manual states 10.4-15.6k ohms
Not really that far out of line, but out on both sides - guess a new coil is in the future.
As to reinstall - I believe what I'm going to do is to mount the new coil further to the rear -on top of the gearbox. Plenty of room there and easy to reach if needed.
Guess I'll hook the rear coil up to front leads and see if machine will run on front cylinder using that coil. If not then for sure it's the coil. Even if it does run, the extra length of the coil leads might be pushing the sensed resistance too high which is why DFI light is coming on.
Stay tuned-
Bought this in early 2020 with 1100-odd hours - ran fine until a month ago when DFI light came on and mule had zero power. Sounds like it's idling just fine but in truth it's idling on one cylinder, the front one.
I can't get the DealerMode to throw any blinks from the DFI light to diagnose, I cleaned the not-so-dirty battery terminals till they were copper-shiny and did make a bit of difference, the DFI light was off for a short time but now it's back on steady after startup. Spark tester in between sparkplug and sparkplug lead shows good fire on front coil but none on rear. I had the plug out and laying on metal to look for spark when running and I saw a single spark. Can't find any documentation as to whether ECU disables the fuel injection when something's out of whack and DFI light on, or if it disables spark, or if DFI light is on because of failed rear coil.
So I decided to try to extract the rear coil-
The rear coil is of course notoriously hard to get to; the service manual says to remove the starter- but get to it I did, with no starter removal - you have to unplug the leads, then using an 8mm box-end wrench, you can loosen the driver-side mounting bolt -the harder of the two to get to - I was then barely able to get my index and social fingers in there to loosen most of the rest of the way, and then finished the job of removal with some long-reach needle nose pliers once I could get on the threads of the bolt. The passenger side is easier because there's more room. I loosened that bolt with a ratchet then was able to get my thumb and finger on it for removal.
Testing the coil windings for resistance shows the following:
Primary reads 0.9 ohms wherein the manual lists acceptable readings of 1.9 to 2.5 ohms
Secondary reads 18.85k ohms, the manual states 10.4-15.6k ohms
Not really that far out of line, but out on both sides - guess a new coil is in the future.
As to reinstall - I believe what I'm going to do is to mount the new coil further to the rear -on top of the gearbox. Plenty of room there and easy to reach if needed.
Guess I'll hook the rear coil up to front leads and see if machine will run on front cylinder using that coil. If not then for sure it's the coil. Even if it does run, the extra length of the coil leads might be pushing the sensed resistance too high which is why DFI light is coming on.
Stay tuned-
