[Solved] Mercedes C180 Low Coolant
My dad has 2013 Mercedes benz C180 with the 1.6L 4 cylinder turbo engine. He is the original owner from New
it has been serviced every 7000 miles with full synthetic oil.
Recently it has Developed a problem where the coolant warning light comes on when the car is left overnight.
it is not losing coolant as I've checked and the radiator is up the full mark. The car runs perfectly fine it doesn't over heat & the temp gauge stays in the middle all the time. the light only comes on first thing when we start the car after it has been sitting for a long time.
Could it be a weak battery? As I have checked most other things including the head gasket test and nothing show up. and the coolant is fairly new it was changed in 2019.
Maybe the coolant level sensor isn't in the radiator. Maybe it's in the reservoir.
Mercedes put a coolant level sensor on the back side of the reservoir tank. It's on the driver's side. If this sensor goes bad, you have to replace the reservoir tank assembly as the sensor is built in. Check the wiring and the plastic, snap on connector at the tank to make sure it's on good condition and properly connected.
You could check the battery but I doubt if it's that more often it's electronic failure it shouldn't come out with the engine turned off. So for some reason it's still getting power and turning itself on could be real stinker tracing that one down good luck on that
3. And one more thought: if your battery delivers 445 CCA instead of the 800 CCA when charged to (only) 11.5 Volts (which is around the lowest battery voltage I have seen on my cars - the voltage at which my batteries are hardly able to crank anything, especially in cold weather) - maybe the battery is not that bad: maybe it is simply undercharged (being regularily not charged enough) due to your dad not driving his car enough? Could be as simple as that. Just charge the battery to its full voltage and re-test.