Mercedes-Benz E320 Problems
RepairPal has identified the most common problems with the Mercedes-Benz E320 based on complaints from actual vehicle owners. We'll tell you what the problem is and what it'll take to fix it.
Brake lamp housings can melt, resulting in a loss of contact for the brake light bulb holder. If this happens, the brake light will not work. Replacement of the damaged lamp housing should correct this problem.
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.
This vehicle has sensotronic brake control (SBC). If the SBC light on the dash illuminates, have the brakes checked. If the SBC is not working, limited brake pressure is delivered to the front brakes, increasing the distance it takes to stop. The SBC hydraulic unit has a specific service life programmed into the control module; follow the manufacturer's recommended service procedure for proper maintenance of the SBC.
A coolant leak may develop form the Radiator due to degradation of its plastic components. Replacement of the failed radiator will be necessary.
PSE system, voice control module, or Tele Aid module failure can cause a lack of audio. These same modules can also cause dead battery conditions when they fail to "time out." Many electronic control modules are active even when the engine is off. If these modules stay active, they will drain the battery, which is why they have a timer built into the modules. The timer shuts down the modules after a preset amount of time (timing out). If a module does not time out, it will stay active and drain the battery.
A squeak from the steering column is often related to a rubber boot in the column or a seal in the power steering rack.
When the engine is running, but the vehicle is not moving, a rattle heard from beneath the vehicle could indicate that one of the exhaust catalytic converters has failed. The substrate (the internal part of the catalyst that reduces emissions) can loosen and bounce around inside the canister section of the converter—the defective unit will need to be replaced. If this problem is ignored, the substrate can break down and reduce to a size that plugs the outlet pipe, which will cause a sudden loss in power.
A rough running motor or lack of power can be caused by a failed distributor cap or rotor, ignition wires (or their resistors), or valve cover gasket leaks. If the valve cover gasket leaks, oil can pool where the ignition wire resistor connects to the spark plug. The resistor can fail and the spark plug may not fire because of a short circuit through the oil.