JLG 1500SJ Dashboard Warning Lights and Symbols

The JLG 1500SJ instrument cluster provides critical warnings and indicators for safe operation of this telehandler/aerial lift. Understanding these symbols helps prevent costly downtime and ensures operator safety.

How to read the colors: Red symbols indicate immediate stop or serious fault; amber warns of caution or pending issue; green/blue show active systems or normal status.

JLG 1500SJ Warning Light Symbols

SymbolNameColorWhat it meansWhat to do
Master Warning (Stop)REDOne or more critical faults demand immediate shutdown on this JLG 1500SJ.Stop machine, refer to fault codes in display.
Master CautionAMBERNon-critical system issue requires attention on the 1500SJ.Check display for specific caution.
Check Engine (MIL)AMBEREngine control system detected a malfunction affecting JLG 1500SJ performance.Have engine diagnosed by dealer.
Engine Oil PressureREDLow oil pressure may cause severe engine damage on the 1500SJ.Stop engine, check oil level.
Battery / ChargingREDCharging system failure on the JLG 1500SJ; battery voltage out of range.Inspect alternator belt and connections.
Coolant TemperatureREDEngine coolant temperature exceeds safe limit for 1500SJ operation.Stop engine, allow to cool; check coolant level.
Brake SystemREDBrake system fault detected on the JLG 1500SJ; braking may be compromised.Stop machine, inspect brake fluid and system.
PParking BrakeAMBERParking brake is engaged on the 1500SJ; release before driving.Release parking brake to proceed.
Seat BeltREDOperator seat belt is not fastened; mandatory for 1500SJ operation.Fasten seat belt immediately.
Low FuelAMBERFuel level is low on the JLG 1500SJ; refuel soon to avoid engine stall.Add diesel fuel to tank.
High BeamBLUEHigh beam headlights are active on the 1500SJ.Dim when approaching other machines.
Hydraulic OilAMBERHydraulic oil level or temperature is outside normal range for the 1500SJ.Check hydraulic reservoir and system.
Overload / CapacityREDLoad on JLG 1500SJ exceeds rated capacity; stability is at risk.Reduce load immediately; lower lift if possible.
MINLow Oil LevelAMBEREngine oil level is low on the 1500SJ; top up to prevent damage.Add recommended engine oil.
Beacon / Rotating LightGREENBeacon is active; the JLG 1500SJ is visible to surrounding personnel.No action needed; ensures safety.
Swing / Slew LockAMBERTurntable swing lock is engaged on the 1500SJ; travel speed may be limited.Release lock for normal operation.
Work LightsGREENWork lights are switched on for the 1500SJ.Turn off when not needed.

17 symbols shown. Icons follow ISO 2575 dashboard standards; exact graphics vary by model year.

Most Important Warning Lights

Engine Overheat

Common causes

  • Low coolant
  • Radiator blockage
  • Fan belt failure

What to do

Stop the JLG 1500SJ immediately, allow engine to cool, inspect coolant level and radiator fins for debris.

Hydraulic System Failure

Common causes

  • Low hydraulic oil
  • Contaminated fluid
  • Pump failure

What to do

Park the 1500SJ on level ground, check hydraulic oil level and filters; contact service if pump noise persists.

Brake System Malfunction

Common causes

  • Brake fluid leak
  • Worn pads
  • Air in lines

What to do

On the JLG 1500SJ, do not operate; check brake fluid reservoir and inspect lines for leaks; call dealer.

Overload Condition

Common causes

  • Excess weight on forks
  • Improper load distribution
  • Load moment system fault

What to do

Immediately lower the load and reduce weight; never bypass overload system on the 1500SJ.

Engine Oil Pressure Loss

Common causes

  • Low oil level
  • Oil pump failure
  • Clogged filter

What to do

Stop the JLG 1500SJ engine; check dipstick and top up oil; if light remains, tow to service.

Frequently Asked Questions

Why is the master warning light flashing red on my JLG 1500SJ?

This indicates a critical fault; stop the machine immediately and check the display for a specific error code (e.g., engine or hydraulic issue).

Can I continue operating with the amber caution light on?

On the 1500SJ, an amber caution means a non-urgent problem; you can finish the current task but schedule service soon as it may worsen.

How do I reset the overload indicator after reducing load?

The overload lamp on the JLG 1500SJ will automatically turn off once the load is within rated capacity and the lift is lowered; no manual reset needed.

What does the hydraulic oil temperature light mean?

It signals that hydraulic fluid is too hot; reduce heavy lifting cycles and allow the system to cool on the 1500SJ to avoid seal damage.

Why does my seat belt light stay on even when buckled?

Check the buckle latch for debris; if the JLG 1500SJ light persists, the seat belt sensor may need replacement at a dealer.

Is it normal for the glow plug light to flash in cold weather?

Yes, on the 1500SJ the glow plug/preheat indicator flashes during preheating; wait until it turns off before starting the engine.