The most common problem that triggers "stop vehicle leave engine running" a malfunction on a Mercedes-Benz is due to a discharged battery.
This error message can affect any 2015 and newer Mercedes-Benz model, including C300, GLC300, E300, C200, C43 AMG, C250, C180, etc.
One or more error messages on instrument cluster:
- Stop vehicle Leave Engine Running
- 12 Volt Battery See Operator's Manual
- Shift to P, Leave Engine Running
If the car is not driven regularly or only on short journeys, it is very common to get the "Stop vehicle leave engine running" error.
The battery symbol and an exclamation mark are displayed on the instrument cluster when the battery voltage drops below 12.5 volts.
When the stop vehicle leave engine running message comes up, various convenience features may be turned off to conserve battery power.
What to do when the "Stop vehicle leave engine running" comes on?
When the error message "stop vehicle leave engine running" shows on the instrument cluster of a Mercedes-Benz, find a safe location to park and let the engine running in Park.
The warning message typically resets in about ten to twenty minutes. During this time, minimize the use of chargers, vehicle lights, blower fans, heated seats, etc., so that the error resets quickly.
Do not leave the vehicle running and unattended.
If you keep getting a "stop vehicle leave engine running" warning too frequently, you may need to replace the main or auxiliary battery. For more help, see the troubleshooting tips below.
Stop Vehicle Leave Engine Running Wait Transmission Cooling
This error message comes up when the transmission and transmission fluid is overheating, which is very common if you use your Mercedes-Benz to tow.
Pullover as soon as it is safe to do so and allow the engine to idle. Wait for the warning message to clear before resuming driving.
Do not drive with the Stop Vehicle Leave Engine Running Wait Transmission Cooling warning on, or you risk causing damage to the automatic transmission.
This error is caused due to one of the following:
- Keeping ignition on with the engine turned off.
- Keeping the radio on but the engine off.
- Leaving the lights on
- Parasitic draw draining the battery when the vehicle is parked
- The battery is no longer holding a charge; test and replace the battery.
- Too many electronic consumers connected to the auxiliary outlets
- Defective alternator or voltage regulator
- Loose battery connection or ground
- Serpentine belt damaged or off.
- Transmission overheating
A weak battery is one of the most likely issues. A possible solution is to charge the battery with a 12-volt trickle charger. You don't need to keep the engine running. This method is recommended if the vehicle is parked at home for an extended time.
Connect a charger to the battery positive and negative jump-starting posts in the engine bay.
If your battery is under the rear seat or trunk area, use the positive terminal and ground in the engine bay to charge the battery installed under a seat or trunk.
Another option is to disconnect the battery, remove it from the car and charge it.
If the error message keeps coming up too frequently, locate the battery, and check the negative and positive connections for corrosion.
If corrosion is present at the battery posts, use a battery terminal brush to clean them.
Also, perform a charging system test. Auto parts stores such as AutoZone or Advanced Auto Parts offer free charging system tests.
If you have difficulty narrowing down this problem, it could be a parasitic draw, loose connection, or a defective SAM (Signal Acquisition Module) module.
The next step in troubleshooting this problem is to perform a full system scan of all the modules on your Mercedes-Benz.
For this step, you will need a scanner that can read Mercedes-Benz modules. Generic OBD2 scanners are not much help, but few popular scanners such as iCarsoft for MB and Foxwell for Benz.