JLG Telehandler 33193 Fault Code: UGM Output Drivers - Fork Tilt Up Valve - Short to Ground
UGM Output Drivers - Fork Tilt Up Valve - Short to Ground · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
Fault 33193 means the UGM (Universal Ground Module/machine controller) detected a short to ground on the fork tilt up valve output (J2-8) or lost current feedback on the tilt return circuit (J3-6). The controller shuts down the fork tilt up valve output and disables both fork tilt up and down functions. It latches until the machine is power cycled and shows as a machine system distress indicator on the display.
High severity. This fault disables both fork tilt up and down operation, which affects load control on the telehandler. It will not damage the engine or hydraulic system by itself, but losing tilt control mid-task is a real operational and safety concern, so treat it as stop-and-diagnose-soon rather than ignore-it.
What does JLG Telehandler error code 33193 mean?
Fault code 33193 is set by the UGM, the machine's central controller, when it detects an electrical problem on the circuit that drives the fork tilt up valve. Specifically, it sees either a short to ground at output J2-8 (the wire feeding the tilt up valve) or a lost current feedback signal on J3-6 (the tilt return circuit that the UGM uses to confirm the valve is working correctly).
When either condition is detected, the UGM protects itself and the machine by turning off the J2-8 output entirely and disabling the current feedback input. Because tilt up and tilt down share the same feedback and control logic on this circuit, both directions of fork tilt are disabled once this fault sets.
This is reported to the operator as a general machine system distress indicator. The fault does not clear itself: it latches until the machine is power cycled, meaning you have to shut down and restart the machine after the wiring issue is corrected before tilt function can return.
What triggers a JLG Telehandler 33193 code?
The UGM sets this fault when it detects a short to ground at output J2-8 (fork tilt up valve) or when it detects a current feedback lost condition on input J3-6 (tilt return) and internally flags that condition as the cause.
Common causes of 33193
- A short to ground in the wiring harness between the UGM output J2-8 and the fork tilt up valve solenoid, from chafed insulation, pinched wiring, or water intrusion.
- A failed or shorted fork tilt up valve solenoid coil that is drawing current to ground instead of switching cleanly.
- A broken, corroded, or disconnected connection on the current feedback circuit at J3-6 (tilt return), causing the UGM to lose its feedback signal.
- Damaged or corroded connector pins/terminals at the UGM connector or at the valve connector that create an intermittent or direct short to ground.
How to troubleshoot JLG Telehandler 33193: first checks
- Inspect the wiring harness between the UGM (J2-8 output) and the fork tilt up valve for visible chafing, pinch points, or exposed conductor touching ground or the machine frame.
- Check the fork tilt up valve solenoid coil for shorted windings or damage, and inspect its connector for corrosion or moisture intrusion.
- Inspect the current feedback circuit wiring and connector at J3-6 (tilt return) for loose, broken, or corroded connections.
- Check the UGM connector itself for bent, backed-out, or corroded pins on the J2 and J3 connector banks.
- After any repair, power cycle the machine since this fault latches and will not clear on its own even if the underlying short is fixed.
How the code clears
This fault latches until the machine is power cycled. No separate clearing step is listed beyond correcting the short to ground or restoring the current feedback signal and then cycling machine power off and back on.
Frequently asked questions
What does fault code 33193 mean on a JLG telehandler?
It means the machine's controller (UGM) found a short to ground on the fork tilt up valve output circuit, or it lost the current feedback signal used to confirm that circuit is working. Both fork tilt up and down are disabled as a result.
Can I still operate the telehandler with fault 33193 active?
You can generally still drive and use other functions, but fork tilt up and down will be disabled since the UGM has shut down that output and its feedback circuit. Avoid relying on tilt function until the fault is diagnosed and cleared.
Why does fixing the wiring not clear the fault right away?
This fault latches in the controller until the machine is power cycled. Even after the short to ground or feedback issue is repaired, you need to shut the machine off and restart it for the fault to clear and tilt function to return.
What is J2-8 and J3-6 on the JLG UGM?
J2-8 is the UGM output that drives the fork tilt up valve. J3-6 is the current feedback input tied to the tilt return circuit, which the UGM uses to confirm the valve output is functioning. A problem on either can set this fault.
Is this an electrical problem or a hydraulic valve problem?
It can be either. The fault is set by an electrical condition, a short to ground or lost feedback signal, but the root cause can be a wiring short, a failed valve solenoid, or a bad connector, so both the wiring and the valve itself need to be checked.
Does fault 33193 affect anything besides fork tilt?
Based on the actions the controller takes, this fault specifically disables the fork tilt up valve output and the shared tilt return feedback circuit, which disables both fork tilt up and down. No other functions are described as affected.