JLG 450A Control Issues: 2000 Ford Dual Fuel Gas/Propane Platform Controls Not Workin

[MikePhua]

A user is experiencing control issues with a 2000 JLG 450A aerial platform, equipped with a Ford dual fuel system (gas and propane). Specifically, the platform controls do not work, while the ground controls function fine. This issue is preventing the platform from operating properly, though ground operators are able to use the platform without problems. Given the dual fuel system, the problem could be linked to the fuel system, the electrical system, or a specific control fault.
Symptoms
The user reports that the platform's controls (onboard) are not responding. The operator is unable to control the elevation, movement, or other functions using the platform’s onboard controls. However, the ground control system is still operating as expected. This suggests an issue with the platform’s electrical or control system, which might not be communicating properly.
Potential Causes

1. Electrical Wiring Issues
   The issue could stem from electrical connections between the platform and ground control system. If the wires or connectors are loose, corroded, or damaged, it could prevent signals from the platform controls from being sent or received properly. This issue would affect only the platform controls, while ground controls would remain unaffected.
   
2. Faulty Control Board
   If the control board or main circuit board that governs the platform controls is malfunctioning, this could be the cause of the issue. Circuit board components can wear out over time, especially in older equipment, leading to problems with signal transmission and control functions.
   
3. Fuel System Issues
   Since the JLG 450A is a dual-fuel machine, either the gas or propane system could be malfunctioning. If there’s an issue with the fuel supply or the fuel switching mechanism, it could affect the power supply to the control systems, causing them to malfunction. It's essential to check if both fuel systems are working properly and supplying the correct power.
   
4. Mode Switch Malfunction
   Many aerial platforms feature a mode switch that allows operators to switch between ground control and platform control. If this switch or its sensors fail, the platform control may not engage, leaving ground control as the only functional option.
   

Potential Solutions

1. Check Electrical Wiring
   The first step is to check the wiring and connections between the platform controls and the ground control system. Inspect all terminals for loose connections, corrosion, or visible damage. Ensuring that all electrical connections are secure and intact could resolve the issue.
   
2. Inspect the Control Board and Switches
   If the wiring appears to be in good condition, the next step is to inspect the control board or circuit board. Look for any signs of damage, such as burnt components or faulty connections. Additionally, check the switches and buttons on the platform controls for any physical malfunctions.
   
3. Examine the Fuel System
   Since this is a dual-fuel machine, check both the gas and propane fuel systems to ensure they are functioning correctly. Inspect the fuel lines, valves, and switches for any blockages or issues. If the fuel system is malfunctioning, it could disrupt the power supply to the controls, so addressing this issue may resolve the problem.
   
4. Check the Mode Switch
   If the platform has a mode switch that toggles between ground control and platform control, make sure the switch is operating properly. If the switch or associated sensors are faulty, it could prevent the platform’s controls from activating. Replacing or repairing this switch may restore full functionality.
   

Conclusion
The issue with the JLG 450A platform controls is likely caused by electrical issues, a faulty control board, a malfunctioning fuel system, or a faulty mode switch. By systematically checking the electrical connections, control board, fuel system, and mode switch, users can identify the root cause of the problem and restore the platform’s functionality. Prompt resolution of the issue will ensure the platform is safe and effective to use for its intended tasks.