How to open the hood on a Mercedes Benz c300?

This blog will explain the procedure to open the hood on the Mercedes Benz C 300 and answer the following questions: what to do after opening the hood of a Mercedes Benz C 300? What are the common problems with the hood in the Mercedes Benz C300? 

How to open the hood on a Mercedes Benz C 300?

To open the engine hood on a Mercedes Benz C 300 follow the steps given below:

• Unlock the vehicle and open the driver-side door.
• Locate the red hood release lever below the dashboard.
• Pull the release lever downwards, and the engine hood will pop up.
• Close the driver’s door and move towards the front of the car.
• slightly lift the hood and push the safety lever inside and then lift the hood completely.

The hood release mechanism in the Mercedes C 300 uses two spring-loaded mechanical latches. The tow hooks located on the underside of the hood lock in the latches when the hood is in the closed position.

A cable is connected to both the latches and the hood release lever located under the driver-side dashboard panel. Both the latches are released simultaneously when the hood release lever is pulled.

The hood is supported by two pneumatic struts located on the rear side. The hood of the Mercedes Benz C 300 can be opened in two positions. The first position is the default stop in the struts and the hood remains open at a 60-70 degree angle.

The second position is the service position, it is unlocked after pressing the button on the left-hand side support strut. The button releases the mechanical lock in the strut and the hood can be opened to full 90 degrees and allowing easier access to the engine.

While closing from the second position, the button must be pressed again so that the strut is not damaged. The hood cannot be closed if the position of the mechanical stop in the strut is not correct. 

To close the hood on the Mercedes Benz C 300, lower the hood to about 8 inches or 20 cm from the closed position and then let it fall down into the mechanical latches. There is no need to apply force while closing, the weight of the hood will close it completely. 

Check if the hood can be lifted slightly, if the hood moves upwards then open and close it again with a little bit more force to engage correctly. It should lock in both the engine hood latches.

What to do after opening the hood on the Mercedes Benz C 300?

The following tasks can be performed after opening the hood on a Mercedes Benz C 300.

• Visual inspection of the engine compartment 

The Mercedes Benz C 300 is powered by a 4-cylinder petrol engine. If there are any external oil and coolant leaks, it is easy to locate. The engine wiring harness can also be inspected for any damage from rodents. 

Performing a periodic visual inspection of the engine compartment can also help to identify any major problems that can lead to expensive engine repairs. It is also a good chance to clean the engine compartment as dead leaves and foliage can accumulate and block the water drains in the cowl top.

• Engine oil level check.

The engine oil level must be checked before starting a long journey, there is an engine oil dipstick in some of the old generation models in the Mercedes Benz C 300. The latest Mercedes Benz C 300 does not use an engine oil dipstick and it can only be checked from the service menu in the instrument cluster.

The engine oil level is measured by an oil level sensor located in the engine oil sump. If the level is low the system will show the engine oil refill quantity. On the engine oil dipstick, the level must be between the minimum and the maximum mark. 

Top up the engine oil by opening the engine oil cap and pouring the required engine oil into the engine. Check the level again after driving for 30 minutes. The correct engine oil level is always determined at the operating temperature of the engine.

• Coolant level

The coolant level in the Mercedes Benz C 300 is checked by opening the coolant level reservoir cap. The coolant reservoir is located on the right-hand side of the engine compartment. The cap of the expansion reservoir must be only opened when the engine is cool and the temperature is below 40 degrees.

The coolant in the reservoir must reach the ‘T’ mark and it covers all the white area in the expansion reservoir. There is a level sensor in the expansion reservoir and it warns the driver when the coolant level is too low.

• Windshield washer fluid.

The windshield washer tank is located on the left-hand of the engine compartment. The cap of the windshield washer tank is marked with blue color. Always use good windshield washer fluid to refill the tank as it helps to clean the dead bugs and dirt from the windshield that normal water cannot do.

A good windshield washer fluid also helps the wiper blades to make better contact with the glass and prevent juddering.

What are the common problems with the hood on a Mercedes Benz C300? 

The common problems with the hood on a Mercedes Benz C300 are explained below:

• Engine hood open warning.

Engine hood open warning message along with an audible tone can come in a Mercedes Benz C 300 even when the engine hood is closed properly. There are two electrical switches in the engine hood latches. If the signal from the electrical switches is not okay, the engine hood opens and the warring can activate in the instrument cluster.

The electrical switches are connected to the front SAM control unit in the Mercedes Benz C 300. In the closed position of the engine hood, the signal from one engine hood must be closed and the other should show open. 

The control unit uses two sensors from a plausibility check and a faulty sensor or open circuit in the electrical light can cause this fault to occur.

• Active bonnet malfunction

This fault message only comes in the Mercedes Benz C 300 that has the optional pedestrian protection system. The engine hood lifters can have an open circuit in the electrical lines or the internal resistance must be greater than 10 ohms.

The engine hood lifters can be replaced to rectify the fault if the electrical lines between the lifters and the SRS control unit are okay.

Conclusion

This blog explained the procedure to open the engine hood on the Mercedes Benz C300. There is a risk of injury and burns after opening the engine hood as certain parts can get very hot. The radiator fan can also turn on to cool the engine. Hence, never wear loose clothing items and avoid opening the engine compartment when the vehicle is running.