Headlamp cleaning systems improve visibility in the dark and prevent dazzling of oncoming traffic through stray light. On this page, find out about the structure of headlamp cleaning systems and how they work.

The ABS/ESP control lamp may light up sporadically on the above-mentioned vehicles. Error codes such as U0077, U0073, U0401 are stored in the error memory of the control unit.

Faulty injection valves could be a possible cause. After visually inspecting the wiring harness and plug connections, the fault memory of the engine control unit should be read out and deleted if necessary.

Vehicles equipped with an electromechanical parking brake can be set to maintenance mode as follows.
Before the brake pads on the rear axle brake callipers can be replaced, the electric actuator motors must be retracted.

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.

If the performance of the air-conditioning system is inadequate when outside temperatures are high, a faulty evaporator temperature sensor (see illustration example) may be the cause. Incorrectly measured values can cause the evaporator to freeze and block the air flow.

When manoeuvring/parking or driving over bumps, the above-mentioned vehicles may make crackling and/or clicking noises. Searching for the cause of this can sometimes be very difficult.

The following problem is observed in the vehicles mentioned above: Vehicle steering sluggish. The reason for this is an insufficient plug connection between the steering angle sensor and the wiring harness (see figure).

Vehicle headlamps focus the light beams generated by the light source onto the road. On this page, find out about the structure of headlamps, and what lighting technology concepts and legal regulations there are, amongst other things. Here you can also find useful practical tips for dealing with plastic cover lenses.

A defective plastic hose of the vent valve on the engine (Fig. 1) can be the cause of rough engine running in the above-mentioned vehicle. Sucking in "false air" can also cause problems with the exhaust emission test.

If the above-mentioned defect is detected, it may be related to a defect in the vacuum system responsible for controlling the turbocharger.

If problems occur with the above-mentioned vehicle after the cooling system has been repaired or opened (high engine temperature, poor heater performance), the cooling system has probably not been bled or vented in accordance with the manufacturer's specifications.