Drive with caution
Engine
Engine Management (Check Engine)
The engine ECU has logged a fault that can affect emissions, efficiency or driveability. The cause must be read from the diagnostic port.
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A calm, plain-English guide to the warning lights you might see on your dashboard — what they mean, how serious they are, whether you can keep driving, and the one-tap booking button if you can't.
Drive with caution
Brakes
ABS — Anti-Lock Braking
The Anti-lock Braking System is disabled. Normal brakes still work, but the vehicle may lock wheels under heavy braking.
Drive with caution
Safety
Airbag / SRS
The Supplemental Restraint System has logged a fault. One or more airbags or pre-tensioners may not deploy in a collision.
Drive with caution
Emissions
DPF — Diesel Particulate Filter
Soot in the filter is above the regeneration threshold. Continued short journeys will block it permanently.
Do not drive
Engine
Oil Pressure
Engine oil pressure has dropped below safe operating level. The engine can seize within minutes if you keep driving.
Drive with caution
Electrical
Battery / Charging
The alternator is not charging the battery. The vehicle is now running on stored battery only.
Do not drive
Brakes
Brake System
Low brake fluid, parking brake left on, or a fault detected in the braking system.
Drive with caution
Tyres
Tyre Pressure Monitoring (TPMS)
One or more tyres has lost pressure, or the TPMS system has detected an issue.
Drive with caution
Emissions
AdBlue / Diesel Exhaust Fluid
AdBlue level is low or the SCR system has a fault. Once the tank is empty, the engine will not restart.
Do not drive
Hybrid / EV
Hybrid System (Red Triangle)
A fault in the hybrid drive system has been detected. Power may cut at any moment.
Drive with caution
Hybrid / EV
EV Charging / High-Voltage Battery
The high-voltage battery system has flagged a charge fault or temperature warning.
Drive with caution
Powertrain
Transmission / Gearbox
The gearbox or transmission control unit has detected a fault. The vehicle may go into limp mode (3rd gear only).
Do not drive
Cooling
Cooling System / Coolant Temperature
Engine coolant temperature is above safe range. Continued driving will warp the head and destroy the engine.
Important
LONS AI™ provides guidance, not a diagnosis. If a red warning light is showing, the safest action is always to pull over, switch off and call us on 0117 427 3457. Recovery is available 24/7.