Injection valves provide each cylinder with the required fuel and simultaneously atomise the fuel so that it can burn most effectively in the combustion chamber. Scroll through this page and find out how injection valves work and potential fault symptoms. You will also find useful tips for performing troubleshooting work on injection valves with the engine running and switched off.

If the above-mentioned defect is detected, it may be related to a problem with the keyless central locking system. Because of water ingress and corrosion affecting the door handle switches, the receiver detects an opening request and sends this signal to the body control unit.

On the above-mentioned vehicles, bulbs for halogen headlamps can be replaced as follows:

• Switch off the ignition
• Disconnect the headlamp from the power supply by unplugging the electrical supply line

Vehicles with an adjustable or sliding sunroof are affected. When the sunroof is opened, water can penetrate into the vehicle interior.

Tyre pressure is an essential safety factor of a vehicle. The most common tire damage can be traced back to a gradual pressure loss. This is often noticed by the driver of the vehicle when it is too late. Insufficient tyre pressure causes increased fuel consumption and poor driving characteristics.

The following symptoms may occur in the above-mentioned vehicles due to faulty engine control unit software:

• Engine cuts out after cold start
• Engine cuts out when disengaging the clutch in coasting mode

The following symptoms may occur in the above-mentioned vehicles due to faulty ESP/ABS control unit software.

Sufficient coolant liquid amount is prerequisite for flawless operating of engine. On this page, we show you the functions of the coolant, the ideal mixing ratio and how to determine the antifreeze content in coolant.

In the above-mentioned vehicles, the engine may cut out again shortly after starting at low outside temperatures (-10 °C). This is often the case when the vehicle has been parked overnight.

With the above-mentioned vehicle, it may happen that the vehicle interior monitoring system, every so often, triggers the vehicle alarm. A faulty ultrasonic sensor of the vehicle interior’s lamp unit is a possible cause.

The classic low beam is in fact a compromise solution, and it's not without its weaknesses. Thanks to its new light functions, the Advanced Front Lighting System (AFS) eliminates the rigid boundaries of the low beam, thereby significantly improving visibility in the dark and in poor weather.

In the above-mentioned vehicles, a software error may cause one headlamp to remain sporadically on after the lights have been switched off.