Problem Reports
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1994 Mercedes-Benz S500 Problems
Squeaking/Worn Brake Pads May Require Rotor Replacement Also
The brakes may begin to squeak at about the 50 percent wear point. This is due to the size and material used for the brake pads and rotors. The brake rotor surfaces become uneven, causing a lip to form at the outer edge. This will generally require replacement of the rotors when the pads are worn (pad life varies depending on driving style and terrain).
The Differential May Develop Leaks From the Seals or Cover
Leaks may develop from the differential cover and/or seals on high mileage or older vehicles. Our technicians recommend a complete reseal of the differential unit if these leaks are addressed.
ABS Modulator Failure Due to Dirty Brake Fluid
As brake fluid becomes dirty over time, it can cause a failure of the anti-lock brake system (ABS) modulator assembly. Our technicians recommend a complete brake system flush every two years to help prevent this issue.
Electrical Issues Due to Degraded Engine Wiring Harness
The engine wiring can degrade because the insulating material falls off leaving the bare wire exposed. This can cause many problems depending on which wires are exposed and what they touch.
Closing Assist/Door Lock Issues Due to Pneumatic System Problems
Problems with the pneumatic system can cause closing assist and door lock issues.
Climate Control System Problems Due to Wear in Climate Control Buttons Contacts
The climate control system can fail or perform erratically due to internal problems with the climate control button electrical contacts. Replacement of the climate control assembly is commonly required to correct this problem.
Excess Free Play in Steering and/or Alignment Issue
One or more of the following steering linkage components may wear prematurely; tie rod ends, drag link, or idler arm. Our technicians remind us the wheel alignment should be checked and adjusted if any of these items are replaced.
Head Light Lenses Become Cloudy/Opaque
Due to exposure to the sun, lenses for head lights may become opaque (cloudy or hazy). This reduces the effectiveness of the lights. Our technicians tell us plastic polishes can improve the clarity of the lenses, but replacement of the lamp housings is the only way to regain the full intensity of the lights.
Coolant Leak Due to Cracked/Broken Heater Core Outlet Housing
A cracked or broken heater core outlet housing can cause a coolant leak near the bulkhead (firewall). Our technicians remind us that coolant leaks should be repaired in order to avoid overheating the engine due to coolant loss.
Erratic Engine Operation and Poor Fuel Economy Due to Faulty Mass Air Flow Sensor
A faulty mass air flow (MAF) sensor can cause erratic/rough engine operation and fuel economy issues. Since this sensor measures the actual amount of air entering the motor, when it fails, the engine control module (ECM) takes the wrong information and delivers incorrect volumes of fuel to the cylinders.
Coolant Hoses May Fail Unexpectedly
The cooling system hoses may fail unexpectedly. The hoses can look good on the outside, but the rubber can degrade and erode on the inside. If not carefully checked, the hoses can burst at any time.
Harsh Ride From Rear Due to Failed Dampening Actuator
Vehicles with automatic level control that ride harshly in the rear (no give in the suspension) may have one or both dampening actuators which have failed. It is commonly recommended the actuators be replaced in pairs.
Engine Oil and Coolant Leaks Resulting in Fulid Intermix
Internal and External engine oil & coolant leaks can develop from the head gasket and/or timing cover gasket; these leaks should be repaired before the engine oil and coolant intermix which can result in severe engine damage.
Throttle Valves May Experience Electrical Failure
The electronic throttle assembly may suffer an electrical failure. It is often cheaper to send the valve to a service center for repair that to purchase a new part.