If you’re here, you probably see a ‘Stop Vehicle Leave Engine Running’ or ‘Stop Vehicle Shift to ‘P’ Leave Engine Running’ message on your dashboard.
This article will help you understand what this means and how to fix it!
The ‘Stop Vehicle Leave Engine Running’ message is triggered by a weak battery. It will disappear after stopping the vehicle and leaving the engine running for 10 to 30 minutes. If it does not disappear, the alternator is defective.
What causes a ‘Stop Vehicle Leave Engine Running’ message?
The ‘Stop Vehicle Leave Engine Running’ message is triggered by a low-voltage battery. Therefore, it is caused by a weak battery or a defective alternator (which charges the battery).
Your Mercedes is asking you to stop the vehicle and leave the engine running so that the battery can be recharged. If you continue driving without stopping, you risk engine damage.
The message can appear on multiple Mercedes-Benz models, including the C300, GLC 300, and E300.
You may also see any of the following messages, which are highly related or equal to ‘Stop Vehicle Leave Engine Running’:
- Stop Vehicle Shift to ‘P’ Leave Engine Running: Equal to ‘Stop Vehicle Leave Engine Running.’
- 12 V Battery See Operator’s Manual: The engine is off, and the battery charge level is too low.
- Battery icon + ‘See Operator’s Manual’: The battery is not being charged.
- Red battery icon + ‘Stop Vehicle See Operator’s Manual’: The battery is no longer being charged, and the battery charge level is too low.
What to do when you see ‘Stop Vehicle Leave Engine Running’
Here is what you should do when you see a ‘Stop Vehicle Leave Engine Running’ message:
- Stop vehicle. If you’re driving, find a safe place to pull over.
- Leave the engine running. As the message suggests, keep the engine running.
- Wait until the message disappears. Depending on the state of your battery and alternator, you must keep your engine running for 10 to 30 minutes. Once the message disappears, you can safely continue driving.
This is the procedure from the official Mercedes-Benz owner’s manual:
How to fix ‘Stop Vehicle Leave Engine Running’
A ‘Stop Vehicle Leave Engine Running’ message can be a one-time occurrence with no underlying issues. But more often than not, your Mercedes will have a weak battery or a faulty alternator.
Generally, a Mercedes battery only lasts for about four years. A Mercedes alternator lasts for about seven years.
To find which of the two is the culprit in your car, you will have to test them.
You can test your Mercedes battery using a multimeter (a device used to measure electrical voltage, current, and resistance).
Here is a step-by-step process to test your Mercedes battery:
- Safety first: Make sure the car is off and the keys are out of the ignition.
- Locate the battery: Open the hood and locate your Mercedes battery. It’s usually easy to find:
- Check for visible issues: Before using the multimeter, visually inspect the battery for any signs of damage or corrosion on the terminals.
- Set up your multimeter: Set your multimeter to the DC Voltage setting, marked as “V” with a straight line (for direct current voltage).
- Connect the multimeter: Attach the red lead of the multimeter to the positive terminal of the battery (usually marked with a + sign or red in color) and the black lead to the negative terminal (marked with a – sign or black in color).
- Read the voltage: A healthy Mercedes battery should show a voltage between 12.6 to 12.7 volts. If it’s below 12.4 volts, the battery is weak and may have triggered the ‘Stop Vehicle Leave Engine Running’ message. If it’s below 12.0 volts, the battery definitely needs a replacement.
Tip: You can learn how to replace a Mercedes battery by yourself here!
If your battery is good, then you probably have a defective alternator.
Here is how to test your Mercedes alternator:
- Start the engine: Turn on the engine. Keep the car in Park (or Neutral if it’s a manual transmission) and apply the parking brake.
- Reconnect the multimeter: Like with the battery test, connect the red lead to the battery’s positive terminal and the black lead to the negative terminal.
- Check voltage with the engine running: With the engine on, your multimeter should now show a higher voltage. Typically, this should be between 13.7 to 14.7 volts.
- Load test: Turn on your car’s headlights, air conditioning, and radio. The voltage should remain stable (within the 13.7 to 14.7 volts range). If it drops significantly, your alternator does not supply enough power and is defective.
If you find that the alternator is defective, you should have it replaced.
If you continue driving with a defective alternator, you will see the ‘Stop Vehicle Leave Engine Running’ message frequently, as well as other Mercedes fault codes, such as ‘PRE-SAFE Functions limited.’
With the steps we’ve outlined, you can confidently assess and address the issue.
Testing the battery and alternator might seem a bit technical, but it’s quite doable with a bit of patience and the right tools.
And remember, if at any point things seem overwhelming, there’s no shame in seeking help from a professional.
Let us know your experience in the comments below; we would highly appreciate it!