The Mercedes Sprinter coolant warning light is informing the driver that the engine coolant temperature is too high. The red symbol is a priority warning and requires immediate attention.
Mercedes Sprinter Coolant Warning Light Comes on While Driving
If the engine coolant temperature warning light comes on while you are driving, being sure to safely observe road and traffic conditions, stop the vehicle as soon as it’s safe to do so and switch off the engine. Continual driving and ignoring the warning light may result in engine failure and expensive repairs.
Usual reasons for the Mercedes Sprinter engine coolant warning light are:
- Low coolant levels – this may be caused by a leak at the coolant reservoir or connecting lines, radiator, water pump etc. Check in the engine bay and under the vehicle engine for any signs of escaping fluids. If the coolant tank requires frequent topping up with water, this is an indication of a leak.
- Sensors – The Mercedes Sprinter coolant temperature sensor sends information to the engine control unit (ECU) and the temperature gauge. It’s not uncommon for the sensor to malfunction, resulting in inaccurate information being sent to the ECU.
Checking Coolant Levels
Stop the vehicle on level ground and away from traffic. The Mercedes Sprinter cooling system is pressurised, particularly when the engine is warm. When opening the cap on the coolant expansion tank, there is a risk of scalding by hot coolant spraying out. The coolant temperature must be below 50 °C (122 °F).
Always allow the engine to cool before opening the cap and ideally wear hand and eye protection when opening the cap. Open the cap slowly at half-turn to allow the pressure to escape.
Once any high pressure has exited the tank, turn the cap fully to remove it. If coolant levels reach the maximum mark on the coolant tank, there is sufficient coolant.
If coolant requires topping up. always use Mercedes-Benz approved corrosion inhibitor and antifreeze to prevent damage to the cooling system.
Mercedes Sprinter Coolant Warning Light Comes on After Restart
If the Mercedes Sprinter engine has been switched off and then restarted after a short period, the high temperature engine coolant dashboard light comes on, it’s usually due to being subjected to extreme loads and harsh driving conditions such as steep gradients.
If the warning light comes on after restart (but it wasn’t on when driving), run the engine for approximately 1 minute at idling speed. If the warning light goes out, continue your journey.
Mercedes Sprinter Dashboard Warning Lights
For all other warning lights and symbols, see Mercedes Sprinter dashboard warning lights.