JLG Scissor Lift 59 Fault Code: Auto Calibration Bosch-EDC Pumps Faulty Operation
Auto Calibration Bosch-EDC Pumps Faulty Operation · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
Fault code 59 (SPN / FMI 13) is set when the Bosch-EDC actuator cannot complete automatic equalization or when the actuator reference values are input incorrectly. It locks out engine stop/start control and prevents the governor from being used until the actuator is recalibrated.
High severity. The engine stop/start function is locked and the governor cannot be used until this fault is cleared, so the machine is not safe to run normally until the EDC actuator is checked and recalibrated.
What does JLG Scissor Lift error code 59 mean?
Fault code 59 relates to the Bosch-EDC (Electronic Diesel Control) actuator that controls engine governing on the JLG scissor lift's diesel engine. This actuator has to complete an automatic equalization process so the controller knows its true position feedback across its range of travel.
When the controller cannot complete this equalization, or when the reference values fed back from the actuator do not match what is expected, it sets fault 59 and flags it under the Actuator fault group with SPN / FMI 13.
The remarks listed for this code make the impact clear: the engine stop/start function gets locked out, the governor cannot be taken into use, and the EDC actuator has to go through calibration again before normal operation can resume.
Common causes of 59
- No automatic actuator equalization possible, meaning the calibration routine cannot complete successfully.
- Incorrect input of the actuator reference values, meaning the feedback values programmed into the controller do not match what the actuator is actually reporting.
How to troubleshoot JLG Scissor Lift 59: first checks
- Check the EDC actuator itself for mechanical binding, damage, or wear, and replace it if required.
- Check the feedback cable running to and from the actuator for damage, loose connections, or corrosion.
- Check the fault limits and reference values stored for the feedback signal against what they should be.
- Program the fault limits for feedback and save the values if they are found to be incorrect.
- Cycle the ignition off and on again after making corrections, then check the system again.
How the code clears
No standalone clearing step is listed beyond the repair sequence. After checking and, if needed, replacing the actuator and feedback cable, and after checking or reprogramming the fault limits and reference values, switch the ignition off and on again and check the system. If it is still faulty, carry out the automatic equalization again and set the fault limits again.
Frequently asked questions
What does fault code 59 mean on a JLG scissor lift?
It means the Bosch-EDC actuator could not complete its automatic equalization, or the actuator reference values were entered incorrectly. This is logged as SPN / FMI 13 under the Actuator fault group.
Can I still start the engine with fault code 59 active?
No. The remarks for this fault state that engine stop/start is locked and the governor cannot be taken into use until the EDC actuator calibration issue is resolved.
What is EDC on this machine?
EDC stands for Electronic Diesel Control, the Bosch system that governs engine speed through an electronic actuator instead of a purely mechanical linkage.
How do I clear fault code 59?
Check the actuator and feedback cable, verify and reprogram the fault limits and reference values if needed, then cycle the ignition off and on. If the fault returns, run the automatic equalization again and reset the fault limits.
Do I need to replace the actuator to fix this code?
Not necessarily. The listed fix starts with checking the actuator and feedback cable and only calls for replacement if the actuator is found faulty. Many cases may trace back to incorrect reference values or fault limits rather than a bad actuator.
Is fault code 59 dangerous to ignore?
It is not described as an immediate safety hazard to bystanders, but since it locks the engine stop/start function and disables the governor, the machine cannot be operated normally until it is corrected, so it should be treated as a stop-work issue.