Ford F-250 / F-350 / F-450 / F-550 Super Duty Warning Lights: What They Mean

Red: stop or act now

Brake System Warning Lamp

Parking brake is applied, or the vehicle has a brake fault or low brake fluid level.
What to do: Make sure the parking brake is off; if the lamp stays on, have the vehicle checked as soon as possible. PDF page 108

Adaptive Steering Loss

The adaptive steering system integrity cannot be verified.
What to do: Do not drive the vehicle; have the system checked immediately. PDF page 107

Amber: check soon

Adaptive Steering Off

The adaptive steering system is off; the steering wheel may not be straight when driving straight.
What to do: If the message persists, have the vehicle checked as soon as possible. PDF page 107

Adaptive Steering Initialization

System detected a difference between steering wheel angle and road wheel angle and is correcting it; normal operation. PDF page 107

Other warnings and indicators

Engine Coolant Temperature

The engine coolant temperature is high.
What to do: Stop as soon as possible, switch off the engine and let it cool. PDF page 109

Engine Oil

With engine running or while driving, indicates a malfunction.
What to do: Stop safely, switch off the engine, check oil level; if it stays on despite correct level, don't drive and have it checked. PDF page 109

Battery

If lit while driving, it indicates a charging system malfunction.
What to do: Switch off unnecessary electrical equipment and have the system checked immediately. PDF page 108

Water In Fuel

The fuel and water separator holds a significant quantity of water and needs immediate draining.
What to do: Stop safely, shut off the engine, then drain the separator. Never drain it while the engine is running. PDF page 111

Service Engine Soon

Emission control malfunction detected. Flashing means engine misfire may be occurring and could damage the catalytic converter.
What to do: If flashing, drive moderately, avoid heavy acceleration and have it checked immediately. If steady, have it serviced at first opportunity. PDF page 110

Powertrain Malfunction/Reduced Power/Electronic Throttle Control

A powertrain or 4WD fault has been detected.
What to do: Have the vehicle checked as soon as possible. PDF page 110

Anti-Lock Braking System

Lit while driving indicates a malfunction; normal braking continues without ABS unless the brake warning lamp is also on.
What to do: Have the system checked as soon as possible. PDF page 107

Front Airbag

If it fails to illuminate at start, keeps flashing or stays on, there is a malfunction.
What to do: Have the system checked as soon as possible. PDF page 109

Stability Control

Shows the system is active. If it stays on or doesn't light at ignition, there is a malfunction and the system switches off.
What to do: Have the system checked immediately. PDF page 110

Low Tire Pressure Warning

Pressure in one or more tires is below the correct level. Flashing indicates a system malfunction.
What to do: Stop and check tires, inflate to proper pressure; if it flashes, have the system checked as soon as possible. PDF page 109

Transmission Tow/Haul

Tow/haul feature is activated. Steady flashing means possible transmission damage.
What to do: If it flashes steadily, have the system checked immediately. PDF page 110

Diesel Exhaust Fluid

DEF is contaminated, low, or the DEF system has been tampered with. PDF page 108

Check Fuel Cap

The fuel cap may not be properly installed.
What to do: Continued driving may trigger the service engine soon indicator. PDF page 108

Check 4X4

A four-wheel drive fault is present. PDF page 108

Low Fuel Level

The fuel level is low or the tank is nearly empty.
What to do: Refuel as soon as possible. PDF page 109

Door Ajar

The ignition is on and a door is not completely closed. PDF page 109

Tailgate Ajar

The tailgate is not completely closed. PDF page 110

Direction Indicator

Left or right direction indicator or hazard flasher is on.
What to do: If indicators stay on or flash faster, check for a burned out bulb. PDF page 109

Fasten Seatbelt

Reminds you to fasten your seatbelt, with a tone. PDF page 109

Wait To Start

Diesel pre-start system is active when the ignition is switched on.
What to do: Wait until it turns off before starting the vehicle. PDF page 110

Stability Control Off

The stability control system has been switched off. PDF page 110

High Beam

High beam headlamps are on; flashes with the headlamp flasher. PDF page 109

Front Fog Lamps

Front fog lamps are on. PDF page 109

Automatic High Beam

The automatic high beam feature is on. PDF page 107

Green: system on

Adaptive Cruise Control

White when the system is on; green when the adaptive cruise control is engaged. PDF page 107

Summarized in our own words from the 2020 Ford F-250 / F-350 / F-450 / F-550 Super Duty owner's manual (AI-assisted; every light name was matched against its cited page 2026-10-18). Your vehicle may not have every light, and other years can differ. A red warning that stays on usually means stop safely and check: your manual has the final word.