What does the first three numbers 94u or 95u stand for on the 518 skidder

Give these guys a call..

https://tractorzone.com/family/skidder/john-deere/440a

The error code "ER20" on a Franklin Log Skidder Q90 likely indicates an issue with the transmission. The exact meaning of this error code may vary depending on the specific skidder model and manufacturer, but it typically indicates a problem with the transmission control system or a sensor within the transmission.
If the transmission will not take gear, this is a clear indication that there is a problem that needs to be addressed. The issue could be with the transmission control system, the transmission itself, or even with the engine.
If you're experiencing this issue, it's recommended to have the skidder inspected by a qualified mechanic or dealership as soon as possible. They will be able to diagnose the problem, determine the cause of the error code, and repair the transmission to ensure it is functioning properly.
If the problem is not addressed, it may cause further damage to the transmission and result in more expensive repairs. Additionally, operating a skidder with a transmission issue can also pose a safety risk to the operator and anyone nearby.

will this help.....

https://www.google.com/search?tbm=isch&q=john+deere+440c+diesel+skidder+wiring+diagram&chips=q:john+deere+440c+diesel+skidder+wiring+diagram,online_chips:skidder+heavy&sa=X&ved=0ahUKEwipjong4_PYAhVNxWMKHTioB40Q4lYILigH&biw=1280&bih=609&dpr=1.5#imgrc=OpH3DGyTuFsYVM:

A parts vendor may know how to obtain a service manual for this 2004 equipment.

Examples using https://www.google.com to search the internet.

https://www.forestryconstruction.com/catalog/franklin-skidder-parts

https://app.equipmentwatch.com/model/forestry-equipment/wheel-mounted-grapple-log-skidders/franklin/q80/22694/specs/logged-out?configurationSequence=1&modelYear=2016

http://www.southernloggintimesmagazine.com/Classifieds/SLT_1211_class.pdf



Google

The 12 v circuit is most likely coming off a small transformer that you toasted when you short circuited the lamps. On low voltage like that it usually doesn't have a fuse other than one built inside the transformer.

if your saying that winch will take in and let out ok but wont hold a load in tension , then your winch directional valve or the winch motor is worn out and is allowing oil to pass right thru it regardless of it not being activated as skidder winches don't have a brake like electric winches do it uses the power of the oil locked into motor to hold a load ( that's also why id never stand under a load suspended by one !!!)

contact the manufacturer on line and quote the machine serial number and ask for an engine serial number that engine.

If reversing the lines doesn't help, see if the winch wants a bleed line, back to tank.

pull the secondary clutch apart on the winch and clean with emory cloth or sand paper and u should see a change in this problem