Hey guys, I've got an old rusted out 873G that purrs like a kitten. Last week, I lost tilt on the bucket, and about 30 seconds later, I lost the arms. Pedals locked when condition is present. Flashing a code that says problem with release solenoids, check for chafed wires or failed solenoids. Says solenoids are getting less than 4V. The solenoids themselves are functioning, as is evidenced by restarting the machine. I get full function for about 15 seconds, then lose tilt, than 15-30 seconds later, lose the arms. Checked all fuses. None are actually labeled for these functions, but all are good, as I'd expect, given the resettable symptom. I have not yet been able to test for voltage at the solenoids. The pins at the connector are ELO style micro pins and I don't have my DVOM adapters at home, gotta remember to bring them home from work. I did Ohm out the solenoids, and while I have no specs to compare with, they did show low resistance as I would expect, vs open circuit. The fact that these lock out solenoids both operate for a short period tells me that they are ok, but that's not proven. It could be that they are setting threshold faults and the computer is shutting the circuit down as a result. Without a wiring diagram, I am at a bit of a loss. Can anyone direct me to a wiring diagram so that I may properly diagnose this issue? I have, of course, done a visual on the various harnesses in the machine and find no chaffing. Even removed the upper right control panel, where one unlocks the bucket controls, with no issues found. Thanks. Brett
Hello Brett, I don't have any info on the 873 G Series, can't help much there, maybe crewchief888 has more specific info on that machine. But according to the codes that you reported, it's unlikely the problem is with either of the cab control panels, the problem would be between the ECM and the lift/tilt lock solenoids. The ground (earth) for these solenoids could be the problem, but again I don't have any info for that model to help.
Thanks willie. A ground issue is certainly a strong probability. This machine has spent most of it's prior life being towed behind trucks in the snow belt. To say it has rotted would be an understatement. Some parts of the 1/4" steel body are now about 1/32" thick, so grounds are probably compromised. A wiring diagram with ground locations is a must for me to sort this out. I'm an auto tech by trade, and a shop owner by choice. There's nothing I can't fix if I have the relevant info.
if i recall, all the grounds terminate back near the battery/starter. 1st place to start is right at the battery, pull the cables, clean them and battery terminals until they bright and shiny. then retest. small amount of corrosion play havoc on the small amperage draws of the electrical system. the spool lock coils are 12v, and release when the key is on, seat bar down, PTO switch is engaged. they get a signal from the main controller. :drinkup
Fix. Replaced spool lock solenoid for bucket tilt. Original ohmed out at 1.2Ohm, replacement at 6.5Ohm. Apparently 1.2 Ohms is low enough resistance to ground for the computer to assume a short to ground and shut down the circuit.