The JCB 155 backhoe loader instrument cluster provides essential feedback for safe and efficient operation. Understanding these indicators helps you monitor machine health and respond to issues promptly.
JCB 155 Warning Light Symbols
| Symbol | Name | Color | What it means | What to do |
|---|---|---|---|---|
| Master Warning (Stop) | RED | A critical fault has been detected on your JCB 155, such as engine shutdown or major hydraulic failure. | Stop the machine immediately, engage parking brake, and consult the fault code display. | |
| Master Caution | AMBER | A non-critical system anomaly is present on the JCB 155; check other warning lights for details. | Review other illuminated indicators and operate cautiously until the issue is resolved. | |
| Check Engine (MIL) | AMBER | The engine management system has detected a fault in the JCB 155's emissions or performance systems. | Reduce load and schedule a diagnostic scan at the nearest JCB dealer. | |
| Engine Oil Pressure | RED | Engine oil pressure in your JCB 155 is below safe operating level, risking severe engine damage. | Shut off engine immediately, check oil level, and inspect for leaks. | |
| Battery / Charging | RED | The JCB 155's charging system is not maintaining battery voltage; alternator or wiring may be faulty. | Turn off non-essential loads and have the charging system tested. | |
| Coolant Temperature | RED | Engine coolant temperature in the JCB 155 has exceeded safe limits, risking overheating. | Idle engine, check coolant level, and inspect for blockages in the radiator. | |
| Transmission Temp | AMBER | Transmission fluid temperature in the JCB 155 is higher than normal; prolonged operation may cause damage. | Reduce load and allow the transmission to cool before continuing heavy work. | |
| Brake System | RED | A fault in the JCB 155's brake system has been detected, potentially reducing stopping ability. | Stop safely, check brake fluid level, and inspect brake lines for damage. | |
| Parking Brake | AMBER | The parking brake on your JCB 155 is engaged; disengage before moving the machine. | Release the parking brake lever fully before attempting to drive. | |
| Glow Plug / Preheat | AMBER | The glow plugs are active in your JCB 155 to aid cold starting; wait for the light to turn off before cranking. | Turn the key to the preheat position and wait until the indicator extinguishes. | |
| Water in Fuel | AMBER | Water has accumulated in the fuel filter/water separator of your JCB 155, which can cause injection issues. | Drain the water separator bowl immediately to prevent fuel system damage. | |
| Low Fuel | AMBER | Fuel level in the JCB 155 is low; refuel soon to avoid running out during operation. | Add diesel fuel from a clean source to the tank. | |
| High Beam | BLUE | High beam headlights are activated on your JCB 155; use only when appropriate for visibility. | Toggle high beam switch as needed for working conditions. | |
| Hydraulic System | RED | A critical hydraulic system fault has been detected on the JCB 155, such as low pressure or overheat. | Stop operations and inspect hydraulic oil level and hoses for leaks. | |
| Hydraulic Oil | AMBER | Hydraulic oil level or temperature in the JCB 155 is outside normal range; check fluid condition. | Park on level ground, check hydraulic oil level, and add JCB-approved fluid if low. | |
| Air Filter | AMBER | The engine air filter on your JCB 155 is restricted; performance may be reduced. | Clean or replace the air filter element according to maintenance schedule. | |
| Service / Hour Meter | AMBER | Scheduled maintenance is due on the JCB 155 based on operating hours. | Refer to the operator manual for required services and perform them promptly. | |
| Work Lights | GREEN | Work lights are active on your JCB 155, providing illumination for night or low-light operation. | No action needed; switch off when not required to save battery. | |
| Beacon / Rotating Light | GREEN | The rotating beacon on your JCB 155 is operating, indicating the machine is active. | Ensure beacon is used in accordance with site safety rules. | |
| Swing / Slew Lock | AMBER | The swing lock is engaged on your JCB 155; the backhoe boom cannot rotate. | Release the swing lock before attempting to slew the backhoe. | |
| Differential Lock | AMBER | The differential lock is engaged on your JCB 155, providing maximum traction in low-grip conditions. | Disengage the differential lock when driving on hard surfaces to avoid driveline damage. | |
| PTO Engaged | GREEN | The power take-off is engaged on your JCB 155, driving an attached implement. | Disengage PTO when not in use to reduce wear. | |
| Low Oil Level | AMBER | Engine oil level in the JCB 155 is below the recommended range; top up soon. | Add engine oil of the correct grade to bring level to full mark. | |
| Brake Fluid Level | RED | Brake fluid level in the JCB 155 is critically low, indicating a leak or worn pads. | Inspect brake system for leaks and top up fluid; have brakes serviced. | |
| Door Open | AMBER | The cab door of your JCB 155 is not fully closed; secure it to prevent dust ingress. | Close and latch the cab door properly. |
25 symbols shown. Icons follow ISO 2575 dashboard standards; exact graphics vary by model year.
Most Important Warning Lights
Engine Overheat
Common causes
- Coolant leak
- Radiator blockage
- Faulty thermostat
What to do
Stop the JCB 155 immediately, allow engine to cool, then check coolant level and radiator fins. If persistent, contact JCB service.
Hydraulic System Failure
Common causes
- Low hydraulic oil
- Pump failure
- Hydraulic hose burst
What to do
Park the machine safely, shut off engine, check oil level and look for external leaks. Do not operate until repaired.
Brake System Malfunction
Common causes
- Low brake fluid
- Brake line damage
- Worn brake pads
What to do
Immediately stop the JCB 155 in a safe area. Check brake fluid reservoir and inspect lines; do not use machine until brakes are operational.
Transmission Overheat
Common causes
- Excessive load
- Low transmission fluid
- Cooler blockage
What to do
Reduce load and let transmission cool. Check fluid level and condition; clean transmission cooler fins if needed.
Low Engine Oil Pressure
Common causes
- Low oil level
- Oil pump failure
- Clogged oil filter
What to do
Stop the engine immediately! Check oil level and add if low. If light remains, do not restart—tow to JCB dealer.
Frequently Asked Questions
What should I do if the Master Warning (Stop) light comes on while operating my JCB 155?
Bring the machine to a complete stop as soon as safely possible, engage the parking brake, and note any fault codes displayed. Do not continue operation until the issue is resolved by a qualified technician.
Why is the Water in Fuel light illuminated on my JCB 155?
This indicates water has separated in the fuel/water separator. Drain the separator bowl immediately to prevent injection pump damage. Check for contaminated fuel sources.
The Check Engine light is on but the machine runs fine. Can I continue working?
You may continue operating the JCB 155, but reduce load and schedule a diagnostic. Prolonged operation may lead to reduced performance or emissions issues.
How do I know if the glow plug light is working properly on my JCB 155?
Turn the key to the preheat position; the amber glow plug light should illuminate and then turn off after a few seconds. If it flashes or stays on, have the glow plug system checked.
What does the differential lock indicator mean?
It shows the differential lock is engaged on your JCB 155 for better traction. Disengage it when traveling on hard surfaces to avoid driveline strain.
The service hour meter light is on. What maintenance does my JCB 155 need?
Refer to the operator's manual for the specific service interval. Typical actions include engine oil/filter change, hydraulic fluid check, and greasing of pivot points.