LSS Platform Overload Detected, All Functions Cut

Common Symptoms

• Platform LCD scrolls fault code 6029-15 and displays an overload warning
• All boom and platform functions cut out immediately, machine will not move
• Alarm horn sounds continuously from the ground control station
• Platform and ground control indicator lights flash or go solid red
• Machine was carrying a load or personnel when the cutout occurred
• Boom was in an extended or elevated position when functions stopped
• Functions do not restore after releasing controls, machine stays locked out

Probable Causes (Ranked by Likelihood)

• Actual weight in the platform, including tools, materials, and personnel, exceeds the rated platform capacity for the current boom position and extension Very Likely
• LSS load cell or pressure transducer on the platform or jib has failed or is reading high due to damage, corrosion, or water intrusion Likely
• LSS calibration has drifted or was corrupted, causing the ADE controller to see an overload at actual weights below rated capacity Likely
• Damaged or pinched wiring harness to the load cell, causing incorrect voltage signal to the ADE controller Possible
• Platform or jib mechanical contact with an obstruction is adding an external downward force that the LSS interprets as overload Possible
• ADE controller software fault or stored fault from a previous overload event that did not clear properly Less Likely
• Hydraulic pressure sensor feeding load data to the ADE controller is out of range due to contamination or internal failure Less Likely

Step-by-Step Diagnostic Procedure

1. Step 1. Remove all personnel and all materials from the platform before doing anything else. Confirm the platform is completely empty and the machine is on firm, level ground.

2. Step 2. Cycle the key switch to OFF, wait 10 seconds, then key back to RUN. Check the platform LCD. If 6029-15 clears with an empty platform, an actual overload caused the event. Recalculate your load against the rated capacity chart on the machine decal before reloading.

3. Step 3. If the fault returns or stays active with an empty platform, connect JLG Analyzer software via the data link at the ground controls. Pull live LSS sensor data and compare the reported load value to actual platform weight. A reading more than 50 lbs above actual weight with an empty platform confirms a sensor or calibration problem.

4. Step 4. Inspect the LSS load cell and its wiring harness at the platform rotator and jib head. Look for crushed conduit, chafed insulation, loose connectors, or visible corrosion at the connector pins. Clean any corroded pins with electrical contact cleaner and reseat the connectors.

5. Step 5. With a multimeter set to DC voltage, back-probe the load cell signal wire at the connector closest to the ADE controller. Key the machine to RUN. With an empty platform you should see a reference signal voltage per the JLG service manual for your model, typically in the 0.5-4.5 V range. A reading pinned at 0 V or at supply voltage (5 V or 12 V) confirms an open or shorted sensor circuit.

6. Step 6. Check that the platform structure itself is not contacting any part of the boom, turret, or an external object. Even light contact can add mechanical load that the LSS reads as overload. Visually inspect all clearances with the boom in the position where the fault triggered.

7. Step 7. If the sensor wiring checks out and the live load reading is still wrong, perform an LSS recalibration using JLG Analyzer software via the data link at the ground controls following the calibration procedure in the JLG service manual for your specific model. This step requires the calibration access code and a known reference weight.

8. Step 8. If recalibration does not resolve the fault, replace the LSS load cell. This is a specialty task. Contact your JLG-authorized service shop for load cell swap and post-replacement calibration.

Frequently Asked Questions