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Why does my Mercedes say Stop Vehicle Leave Engine Running?

Why does my Mercedes say Stop Vehicle Leave Engine Running?

Stop vehicle leave engine running is a sign on the dashboard screen when the Mercedes battery drops the voltage below 12 volts. A battery with several internal defects triggers this warning frequently. 

Why does my Mercedes say, Stop Vehicle Leave Engine Running? You can see a warning sign, “Stop Vehicle Leave Engine Running,” on your Mercedes dashboard due to a malfunctioning battery with no charge, broken old battery, excessive power drain, and unknown current draw. It can also happen due to a broken charge supplier and internal circuit heat. 

Insufficient internal charge of the battery can cause this notification. The following are some reasons for this warning.

Malfunctioning battery with no charging

The auxiliary battery of the Mercedes gets the electric energy from the engine. Therefore, it can work at the standard efficiency level.

It can hold a maximum amount for charge in standard working conditions. However, lack of maintenance and water loss reduces its charging ability.

It lacks the standard saturated charge for optimized functionality. A sign appears on the dashboard screen, which shows the faults of the battery. 

You can solve the problem with compressive troubleshooting. Also, service it after 8 to 10 months and clean its cells.

Maintenance and repair can improve its charge-holding capacity. In severe conditions, replace the Mercedes battery with a new option. 

For replacement, park the car and pull the emergency brakes. For the swap, open the hood and find it. 

Remove its cables with a 10mm socket and pull the upper mounts. Detach the lower mounts with a correctly sized socket of 13mm.

Pull the negative wire and loosen the 10mm mounting bolts. Pull the wires and remove the clamps. 

Remove the battery from the car hood and adjust the new equipment on the mounting tray. Readjust the mounting bracket and reassemble the connecting wires. 

Broken battery

The average lifespan of a Mercedes Benz battery is around 4.5 to 4.9 years. With adequate maintenance, their life expectancy increases. 

Due to pressure of load pressure, the battery cracks and leads to power drainage. However, it can regulate several charge cycles. 

Due to higher temperatures, their insulation cracks and causes wattage leaks. Cold temperatures can crack their bodies and damage the overall equipment. 

The incorrect installation and built-in defects are prominent reasons for its cracks. In addition, it breaks due to short-distance driving, frequent stops, and low operating temperatures.

It can cause sign which requires troubleshooting and repair. For repairs, you can add sealing material to the cracks. Hide the holes and reduce the power leakage. 

Also, repair the broken terminals and connectors by replacing them. For this procedure, pull the old wired and check the style and layout of the terminals. 

With a soft duster, wipe the surrounding connectors. Cut the wires and their strips with a sharp cutter. 

With shrinking, combine the cords and connect them with the mounting point. 

More use and excessive power drain 

The power drainage increases due to the excessive use of electric appliances inside the Mercedes Benz. As a result, it can drain more amperes from the equipment and triggers the sign. 

The additional use of charging ports and US inlets can drain the power at a higher speed. In addition, several people leave their radio and sound system ON for several hours, which affects the drain pattern. 

The excessive use of lights causes the defect of the auxiliary battery due to abnormal drainage. To reduce the power drainage and remove the sign, reduce electric power consumption. 

Turn off the electric amenities and stabilize the power flow. In addition, use the headlights for a short span and turn them off when you are not using them. 

Provide different intervals to your infotainment equipment. It can reduce the current consumption, optimize the ampere flow, and improves life expectancy.

Unknown current draw 

Sometimes, the power drainage increases without a known cause which results in the notification. Different things can trigger the excessive current draw.

Mercedes Benz has glove lights that turn off when you close the door. Due to their internal damage, they do not switch off, and power keeps flowing through them.

They can absorb a small amount of voltage due to their layout. However, the continuous power draw for more than 5 to 6 hours results in drainage.

The lights underneath the hood and headlights remain ON. These are unknown power consumers, which can pop up the warning.

However, you can resolve this problem by checking the amenities which consume more current. Then, unplug the other devices and remove the chargers from the ports.

During park conditions, turn off the cabin lights and external headlamps. Open the hood and check the lights and unplug their source of power.

Close the doors according to standard instructions and lock them to remove the input signals that keep the lights on. 

Broken or corroded charge supplier

The Mercedes Benz battery comprises a tiny device that can charge them. The alternator breaks due to current surges.

With internal faults, it cannot provide enough charge to the battery. In addition, the moisture causes corrosion over the alternator, which cannot convert the horsepower into the current.

As a result, the auxiliary equipment does not get enough energy for charging and performance. It drains the battery at accelerations and results in premature faults.

You can repair the corroded diode with cleaning and maintenance. However, its replacement is a better solution to stabilize its performance.

You can find the alternator on the lower side of the engine cylinders, which are on the passenger side. Untighten its three mounting bolts with a socket.

With the vacuum lines, the valve connects with the engine. Pull the valve from the bracket and remove the air hose.

Approach the flexible clip that holds the harness with it. Hold it firmly and cut it with a sharp tool.

Loosen the upper bolts and unscrew them manually. Remove the broken alternator and slide in the new option.

Adjust the leads and tighten the nuts with the threading technique. Rearrange the covers and re-tighten the nuts.

Against the cover, adjust the four bolts with threads. With a wrench, tighten them and fix their position. 

Internal heat of circuit 

The Mercedes Benz battery comprises a current regulator inside the system that controls the voltage flow. It prevents extra power drainage due to its functions. 

Due to a malfunctioning ampere regulator, you can see the sign on the screen. In addition, excessive heat and pressure can burn the regulator.

It cannot stabilize the electricity flow inside the vehicle. In addition, due to circuit heat, the equipment resistance reduces, which affects the voltage.

It reduces its lifespan and requires replacement. Remove the sign by replacing it with the following method. You can find it on the upper side of the alternator. 

Adjust the car in park mode and switch off the current flow. Find the battery inside the trunk and remove its connectors.

Assess the cover of the regulator; untighten the 11mm and 15mm nuts. Detach the screws and assess the current regulator. On the mounting spot, loosen the three different bolts. 

Hold the carbon leads, push them inside and slide the new ampere regulator. With a Philips screwdriver, tighten all the screws.

With a ratchet, adjust the rear cover and readjust everything. 

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