JLG Telehandler 2345 Fault Code: Ground Controls - Boom Angle Sensor - Out of Range Low
Ground Controls - Boom Angle Sensor - Out of Range Low · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
Fault 2345 sets when the JLG telehandler's ground module (UGM) sees a boom angle sensor signal below 0.6 volts. The machine locks the displayed boom angle at a fixed value of 99, derates lift-up capability, and ignores hydraulic function requests from the platform module until the machine is power cycled.
High severity. This code causes the machine to derate lifting performance and block hydraulic function requests from the platform module. It signals a real system distress condition, so the machine should not be relied on for normal lift work until the sensor circuit is fixed.
What does JLG Telehandler error code 2345 mean?
Fault 2345 means the ground control module (UGM) has detected that the boom angle sensor signal has dropped below 0.6 volts, a level considered out of range low. The boom angle sensor tells the machine's controller what angle the boom is currently at, which is critical information for calculating safe lift capacity and preventing tip-over or structural overload.
When this fault is active, the machine no longer trusts the real boom angle. It substitutes a fixed placeholder value of 99 on the operator's cabin display so the operator and system have a visible flag that the real reading is not available. The controller also reduces (derates) the maximum lift-up capability, and it stops honoring hydraulic function requests coming from the platform module, since it cannot verify boom position safely.
If a calibration procedure is in progress when this condition occurs, that calibration will fail and post a 'calibration: sensor fault' message. This is the ground controls variant of the fault, meaning it is detected by the ground control module rather than the platform module.
What triggers a JLG Telehandler 2345 code?
During operation or during a boom angle sensor calibration, the UGM detects a signal at this input of less than 0.6 volts. The fault latches active until the machine is power cycled, even if the signal returns to a normal range.
Common causes of 2345
- A wiring fault in the boom angle sensor circuit, such as a short to ground, that pulls the signal voltage down below the 0.6 volt threshold.
- A failed or failing boom angle sensor that is no longer outputting a valid signal voltage.
- A loose, corroded, or disconnected connector at the sensor or along the harness back to the ground control module.
- Damage to the sensor harness from vibration, pinching, or exposure to weather and debris over time.
- An internal fault in the ground control module (UGM) input circuit, though this is less common than wiring or sensor issues.
How to troubleshoot JLG Telehandler 2345: first checks
- Inspect the boom angle sensor and its connector for visible damage, corrosion, or looseness. Clean and reseat the connector if needed.
- Trace the sensor wiring harness back toward the ground control module, looking for pinch points, chafing, or exposed wire.
- Check for a short to ground in the sensor signal circuit using a multimeter, since a value below 0.6 volts is what triggers the fault.
- Confirm the sensor is receiving proper supply voltage and that ground connections are clean and tight.
- If the wiring and connectors check out, test or replace the boom angle sensor itself to rule out an internal sensor failure.
- After any repair, power cycle the machine since the fault latches until power is cycled and will not clear on its own.
How the code clears
This fault latches until the machine is power cycled. There is no separate reset procedure listed beyond correcting the underlying voltage condition and cycling power to the machine. Simply restoring a normal signal voltage while the machine stays powered on will not clear the latched fault.
Frequently asked questions
What does fault code 2345 mean on a JLG telehandler?
It means the ground control module detected a boom angle sensor signal below 0.6 volts, which is treated as out of range low. The machine responds by locking the displayed boom angle at 99, derating lift-up capability, and ignoring platform module hydraulic requests.
Why does my JLG display show a boom angle of 99?
A displayed value of 99 is a fixed placeholder the controller assigns when fault 2345 is active. It does not reflect the real boom angle. It is a signal that the boom angle sensor input is out of range low and cannot be trusted.
Will the machine still lift with fault 2345 active?
Lift-up capability is derated by an amount set in the machine's constant data tables, and hydraulic function requests from the platform module are ignored. The machine is not operating normally and should be repaired before returning to full lift work.
How do I clear fault code 2345 after repairing the sensor?
Fix the wiring or sensor issue causing the low voltage signal, then power cycle the machine. The fault latches until power is cycled and will not clear just by restoring a normal signal while the machine stays on.
Can this fault fail a boom angle calibration?
Yes. If a calibration is in progress when the UGM detects the signal below 0.6 volts, the calibration fails and posts a 'calibration: sensor fault' message.
Is fault 2345 the same as a platform side boom angle fault?
No. This is the ground controls version of the boom angle out of range low fault, detected by the ground control module (UGM). A platform side version may exist separately but is not covered by this code.