JLG Telehandler 2346 Fault Code: Ground Controls - Boom Angle Sensor - Not Responding
Ground Controls - Boom Angle Sensor - Not Responding · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
Fault 2346 sets when the JLG telehandler controller commands the main lift up or lift down valve at 900 mA or more for 4 seconds with the engine running, but the boom angle sensor shows no appreciable change (less than 0.5 degrees, adjustable in constant data) at that input. The system treats this as a machine system distress condition, freezes the displayed boom angle at 99, blocks calibration, and restricts lift up function until the machine is power cycled.
High severity. The controller locks out or derates lift up function and ignores platform hydraulic requests until power is cycled, which affects normal boom operation. It is not an immediate engine or occupant hazard by itself, but it removes a safety-relevant feedback signal used for lift control, so it should be diagnosed before continued lift use.
What does JLG Telehandler error code 2346 mean?
Fault code 2346 means the ground controls module commanded the boom to move using the main lift up or main lift down valve, but the boom angle sensor did not report any meaningful movement back to the controller. The controller expects the angle reading to change once the lift valve is actively driven with enough current for long enough. If it does not, the controller assumes the sensor or its signal path is not responding.
Because boom angle is used for lift capacity calculations and safety interlocks, the controller reacts by freezing the displayed angle at a fixed placeholder value of 99, refusing any attempt to calibrate the sensor, and ignoring hydraulic function requests coming from the platform module. It will also either shut off lift up entirely (if a platform is attached or platform mode is active) or reduce the maximum lift up rate using a preset derate value, depending on the machine's configuration.
This fault will not appear while the boom angle sensor calibration procedure is actively running, since calibration itself involves moving the boom without stable angle feedback.
What triggers a JLG Telehandler 2346 code?
The fault sets when either the main lift up valve (J2-11) or the main lift down valve (J2-22) is actively driven at a current of at least 900 mA for a period of 4 seconds, with the engine running, while the boom angle sensor input shows no appreciable change, defined as less than 0.5 degrees movement (this threshold is adjustable in the constant data tables). The fault is latched until the machine is power cycled and will not be reported during boom angle sensor calibration.
Common causes of 2346
- Boom angle sensor has failed internally and no longer produces a changing signal when the boom moves.
- Wiring or connector fault between the boom angle sensor and the ground controls module, including corrosion, a loose pin, or a broken wire, preventing the signal from updating.
- Mechanical linkage or mounting issue at the sensor, such as a slipped, disconnected, or worn linkage, so the sensor itself does not move even though the boom does.
- Main lift up or lift down valve is mechanically stuck or the boom is physically restricted from moving, so there is no actual angle change even though the valve is commanded.
- Sensor calibration data is corrupted or lost, causing the module to misread the sensor even if the sensor itself is functioning.
How to troubleshoot JLG Telehandler 2346: first checks
- With the machine safely shut down, inspect the wiring harness and connectors at the boom angle sensor for corrosion, looseness, or damage, and repair or clean as needed.
- Check the physical linkage or mounting of the boom angle sensor to confirm it moves freely and stays connected as the boom is raised and lowered.
- Verify the main lift up valve (J2-11) and main lift down valve (J2-22) connectors and wiring are intact and that the valves are not mechanically stuck.
- With the engine running and a helper watching the display, carefully command a small lift up or lift down movement and confirm whether the displayed boom angle changes at all or stays fixed at 99.
- Check for any other active faults related to the boom angle sensor or ground controls module that might point to a shared wiring or power supply issue.
- Confirm the machine is not currently in boom angle sensor calibration mode, since the fault is suppressed during that procedure and a stuck calibration attempt can mask the real issue.
How the code clears
This fault latches until the machine is power cycled. After completing repairs, cycle the key off and back on to clear the fault, then verify the boom angle display no longer shows the fixed value of 99 and that lift up function has returned to normal. If the fault resets immediately, recheck the sensor signal and wiring before returning the machine to service. No separate clearing step or reset procedure is listed beyond the power cycle.
Frequently asked questions
What does JLG fault code 2346 mean?
It means the ground controls module tried to move the boom using the lift up or lift down valve but the boom angle sensor did not show any meaningful change in reading, so the controller assumes the sensor is not responding.
Why does my JLG telehandler display show boom angle 99?
When fault 2346 is active, the controller displays a fixed placeholder boom angle value of 99 on the operator's cabin display instead of the real angle, since it can no longer trust the sensor reading.
Can I still use the boom after fault 2346 sets?
Lift up function is either shut off completely, if a platform is attached or platform mode is active, or reduced using a preset derate value. Hydraulic requests from the platform module are also ignored until the fault is cleared.
Why won't the boom angle sensor calibrate after this fault?
The controller disallows calibration while fault 2346 is active and will show a boom angle calibration fail message. The sensor issue causing the fault needs to be fixed first.
How do I clear fault code 2346 on a JLG telehandler?
The fault is latched until the machine is power cycled. Cycle the key off and back on after repairs are made and confirm the boom angle display and lift up function return to normal.
Will this fault show up during boom angle sensor calibration?
No. The fault is specifically suppressed during the boom angle sensor calibration procedure, since normal angle feedback is not expected during that process.
What are the most likely causes of a boom angle sensor not responding fault?
The most common causes are a failed sensor, damaged or corroded wiring or connectors between the sensor and controller, a disconnected or slipped sensor linkage, or a mechanically stuck lift valve or restricted boom that prevents actual movement.