Peugeot 407 (2004 - 2008) warning lights: check engine or AdBlue warning light on

If the AdBlue warning light stays on after refilling your Peugeot 407, the system may not yet have registered the refill, or there may be a fault with the AdBlue dosing system or its electronics. Some vehicles need to be driven for several kilometres before the display updates. In other cases, diagnosis, repair or a supported reset with a tool such as klavkarr may be needed.

See the procedure for resetting the AdBlue warning light on a Peugeot 407.

With klavkarr and its dedicated app, you can access the car's control unit and reset the service reminder after changing the oil, where this function is supported. This prevents the reminder from staying on after maintenance is complete.

It usually indicates an anti-lock braking system fault: a faulty wheel speed sensor, damaged ABS encoder ring, broken wiring or a problem with the hydraulic unit. Electronic diagnostics identify the code stored by the ABS control unit, helping you target further checks and repairs.

See our guide to resetting the ABS warning light on a Peugeot 407.

It indicates a potential engine or emission-control problem, ranging from a minor fault to a more serious malfunction. A diagnostic scan with a klavkarr scanner for Peugeot 407 helps you investigate the cause before deciding what to do.

What exactly is an engine fault?

It can range from a minor issue to a serious malfunction that affects petrol or diesel engine performance or, in the worst case, causes permanent damage.

What should you do if a warning light comes on in your Peugeot 407?

If an engine, airbag, ABS, ESP or other warning light comes on, act cautiously and follow your vehicle handbook. A compatible diagnostic scanner can read the stored fault information and help you investigate the cause.