JLG Telehandler 33231 Fault Code: UGM Output Drivers - Right Stabilizer Up Valve - Open Circuit
UGM Output Drivers - Right Stabilizer Up Valve - Open Circuit · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
Fault code 33231 sets when the UGM (upper ground module) detects an open circuit on the right stabilizer up valve output, but only when stabilizers are enabled in the machine setup menu. The controller responds by shutting down all four stabilizer valve outputs (right up, right down, left up, left down) and the fault stays latched until the machine is power cycled.
High severity. This code disables all stabilizer functions at once, which can stop leveling and outrigger operations mid-task. It is not an immediate engine or structural safety event, but a machine that relies on stabilizers should not be used for lift or platform work until this is fixed.
What does JLG Telehandler error code 33231 mean?
Fault code 33231 is logged by the UGM (upper ground module) when it detects an open circuit on the output that drives the right stabilizer up valve. This only applies on machines where the stabilizers have been configured in the machine setup menu.
When the UGM sees this open circuit, it does not just disable the one valve. It deactivates all four stabilizer valve outputs: right stabilizer up (J2-3), right stabilizer down (J2-15), left stabilizer up (J2-10), and left stabilizer down (J2-21). This means the whole stabilizer system goes offline together, not just the one leg with the wiring problem.
The indicator for this fault is listed simply as machine system distress, meaning the machine will flag a general distress condition on the operator display rather than a narrowly worded stabilizer message.
What triggers a JLG Telehandler 33231 code?
The stabilizers must be configured (enabled) in the machine setup menu, and the UGM must detect an open circuit condition at the right stabilizer up valve output for the fault to set.
Common causes of 33231
- A broken, disconnected, or corroded wire in the circuit feeding the right stabilizer up valve
- A failed or damaged connector pin at the valve or at the UGM output (J2-3)
- A bad solenoid coil on the right stabilizer up valve that presents as an open circuit
- A wiring harness fault upstream or downstream of the valve, such as a chafed or cut wire causing loss of continuity
How to troubleshoot JLG Telehandler 33231: first checks
- Inspect the wiring harness and connectors running to the right stabilizer up valve for visible damage, corrosion, or loose pins
- Check the connector at the UGM output J2-3 for proper seating, corrosion, or bent pins
- Verify continuity through the right stabilizer up valve coil and its wiring back to the UGM
- Confirm in the machine setup menu that stabilizers are configured as expected for this machine, since the fault only applies when stabilizers are enabled
- Check the other three stabilizer valve circuits (J2-15, J2-10, J2-21) since they are all deactivated together, which can help you tell whether the problem is isolated to one valve or part of a shared harness issue
How the code clears
This fault latches until the machine is power cycled. After making a repair, cycle machine power off and back on to attempt to clear the fault code. No separate reset procedure is listed for this code beyond the power cycle.
Frequently asked questions
What does fault code 33231 mean on a JLG telehandler?
It means the UGM (upper ground module) has detected an open circuit on the output that drives the right stabilizer up valve. This only triggers on machines where stabilizers are configured in the setup menu.
Why did all my stabilizer functions stop working, not just the right up valve?
When this fault sets, the UGM deactivates all four stabilizer valve outputs together: right stabilizer up, right stabilizer down, left stabilizer up, and left stabilizer down. This is a built-in safety response, not a separate failure in each valve.
Will turning the machine off and on clear code 33231?
A power cycle is the listed way this fault clears. If the underlying wiring or valve problem is still present, the fault will likely return once the UGM detects the open circuit again.
Can I keep operating the telehandler with this fault active?
Since all stabilizer outputs are disabled when this fault is active, any work that depends on stabilizers should not be attempted until the open circuit is found and repaired.
What usually causes an open circuit on a stabilizer valve output?
Common causes include damaged or corroded wiring, a bad connector pin at the valve or at the UGM output, or a failed solenoid coil that no longer completes the circuit.
Does this fault code apply to machines without stabilizers?
No. The fault only sets on machines where the stabilizers have been configured in the machine setup menu. If stabilizers are not configured, this fault condition does not apply.
Where do I start looking for the open circuit?
Start at the right stabilizer up valve connector and its wiring, then check the connector at the UGM output labeled J2-3, checking for corrosion, loose pins, or damaged wire before moving to a full continuity test.