Skyjack SJ4740 Will Not Lift, Pothole Guard Fault

Confirmed cause: The main chassis wiring harness for the left pothole guard was damaged internally. The wires were broken inside the protective loom about 12 inches from the switch connector, likely due to fatigue from years of vibration. Repair performed: A new section of wire was spliced into the harness to bypass the damaged section. The new connections were made using sealed heat-shrink butt connectors, and the repaired section was protected with new convoluted tubing and secured to the chassis. Verification: After the repair, the machine was started. The lift function operated normally. Lowering the platform caused the pothole guards to deploy as expected. Driving the machine with the platform raised now correctly functions at a reduced speed. No alarms were present. Technician notes: - This fault can be intermittent at first if the wires are only partially broken. - Always check both pothole guard switches; this fault was on the left side, but the right side could also be a cause. - The lack of a specific fault code on this model for this condition can be misleading. The system simply sees an unsafe state (pothole guards down) and prevents lifting, without logging a specific component fault.