JLG 1930ES Drive Motor Overheating on Ramps
Fault Codes & Symptoms
Drive motor overheats Related symptoms: - Loss of drive power on one side under load - Intermittent drive speed issues - Motor controller fault codes (though none were present here) The left drive motor is getting very hot and the machine loses power when climbing the ramp into our building. It works fine on flat ground.
Confirmed cause: The motor controller was faulty. The internal power driver for one of the motors was failing under heavy load, leading to incorrect phasing and excessive current draw, causing the motor to overheat. Repair performed: Replaced the motor controller. Calibrated the new controller to the machine using the JLG analyzer software. Verification: Operated the machine up and down the same ramp multiple times. Both drive motors now maintain a similar, normal operating temperature under load. Technician notes: - This fault would not have been found without testing the machine under the specific load conditions described by the customer. Swapping connections at the controller is a fast and effective way to isolate a motor or controller issue without needing to swap the heavy motors themselves. - Always perform the controller calibration procedure after replacement to ensure proper machine operation.