The evaporator temperature sensor can fail, causing the AC compressor not to cycle. If the AC compressor does not turn on, the AC system will not blow cold air. If the compressor is stuck on, the air will be very cold at first, before warming up.
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Newest reported Mercedes-Benz S430 4MATIC problems
The engine may develop a stalling and/or no start condition due to a failed crankshaft position sensor.
The center console armrest can break. Replacement is commonly the recommended repair.
Analog Tele Aid units are no longer supported and must be updated to digital, preferably at a dealership or a well-equipped independent shop. The update and all related factors should be completed at the same time.
An engine Oil leak may develop from the PCV vent housing on the valve cover and/or the inspection plate on the front of the engine.
The rubber bond in the harmonic balancer can decay, which causes the balancer to move and work its way toward the timing cover. If the balancer comes into contact with the timing cover while the engine is running, it will fracture and damage the cover and potentially other surrounding parts. The harmonic balancer should be inspected at every service.
The electrical connector at the automatic transmission may leak fluid into the wiring harness. If not repaired, the oil will migrate through the wiring harness and damage the transmission control module. A new harness and control module may be necessary to correct this problem.
CD changers, command units, voice control units, PSE units, and Tele Aid units are prone to failure, especially in early models.
The relay which turns the airmatic suspension pump on may fail causing the pump to run continuously. This can result in failure of the pump motor or a dead battery as the pump motor will continue to run after the car is turned off. Also, Worn airmatic pump mount bushings can causes noises in the front axle while driving on bumpy roads or a buzzing noise while the pump is running.
Due to the size and material used on the brakes of these vehicles, the brakes may start to squeak around the 50 percent wear point. The brake rotor surfaces become uneven, causing a lip to form at the outer edge of the rotor. Because of this, the rotors are usually replaced when the pads are worn (pad life varies depending on driving style and terrain).
High mileage or older vehicles commonly develop leaks from the differential seals and/or cover. Our technicians recommend a complete reseal of the differential unit whenever these leaks are repaired.
An engine oil leak may develop from the oil level sensor. Replacement of the leaking sensor will commonly correct this concern.
A door control module/actuator may fail. Our technicians recommend finding an expert to repair them. Taking the door trim panels off requires expert knowledge because they can break and the pieces are very expensive.