Having trouble with parking brake on 544H. The machine would apply parking brake randomly. I have checked all connections for corrosion and broken wires. I have used related threads to diagnose this issue checking volts and resistance accordingly. I had determined the TCU to be the issue and replaced it with a new one from the dealer. The machine was used the day before and drove into the shop to have the TCU replaced. After the TCU was installed I turned on the key and the display showed 0FNR. There is no change when moving the shift lever FWD or REV, nor when switching between gears. My question is... does the new TCU need to be calibrated or programmed thru the dash and if so what is the procedure?
I have never experienced a TCU that came preprogrammed from Deere. After you get the TCU programmed check/replacing your brake accumulator will likely solve your issue.
TCU's for JD wheel loaders are pre-programmed because they are not from Deere. When the TCU is replaced the monitor has to be reprogrammed. See attachment.
Thank you for the information mg2361, went thru the steps and the loader is working properly and park brake has not acted up.