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Mercedes Benz C250 Thermostat Replacement - Check Engine Light Still On
Hello,
I recently received a code for a faulty thermostat (p0128) on my 2013 C250 Sport. I knew the replacement was needed as I noticed in the winter months that the heater would take forever to warm up and the operating temperature wouldn't raise above 60 degrees. Well anyways, about a week ago when I was driving, the check engine light came on and I used an OBD tool to confirm that it was the thermostat. I then ordered a part online, replaced the thermostat, and the operating temperature seems to be back to normal (80-90) even on warm days. The only problem that I am having now is that the check engine light still shows the code for P0128. I have tried clearing the code with an OBD tool as well as pulling negative and positive off the battery for 30 mins, but neither of those options worked. After that, I went back and check the two pigtails that were pulled off to make sure that they were making contact, as well as checked fluid level and hoses to see if anything was potentially leaking. There was no leak and all the connections and hoses seemed to be situated fine. I know the next thing that I would probably have to try would be to ohms test the coolant temperature sensor, but I shouldn't have to since it was a brand new part and it came as an entire assembly. Has anyone else had a similar problem? And if so how did you go about getting rid of the check engine light?
Hello,
I recently received a code for a faulty thermostat (p0128) on my 2013 C250 Sport. I knew the replacement was needed as I noticed in the winter months that the heater would take forever to warm up and the operating temperature wouldn't raise above 60 degrees. Well anyways, about a week ago when I was driving, the check engine light came on and I used an OBD tool to confirm that it was the thermostat. I then ordered a part online, replaced the thermostat, and the operating temperature seems to be back to normal (80-90) even on warm days. The only problem that I am having now is that the check engine light still shows the code for P0128. I have tried clearing the code with an OBD tool as well as pulling negative and positive off the battery for 30 mins, but neither of those options worked. After that, I went back and check the two pigtails that were pulled off to make sure that they were making contact, as well as checked fluid level and hoses to see if anything was potentially leaking. There was no leak and all the connections and hoses seemed to be situated fine. I know the next thing that I would probably have to try would be to ohms test the coolant temperature sensor, but I shouldn't have to since it was a brand new part and it came as an entire assembly. Has anyone else had a similar problem? And if so how did you go about getting rid of the check engine light?
So , i have the same problem , i change thermostat , and after some minutes ,it came the light engine on , you still have this problem ? How you make it , or what was ?
Hello,
I recently received a code for a faulty thermostat (p0128) on my 2013 C250 Sport. I knew the replacement was needed as I noticed in the winter months that the heater would take forever to warm up and the operating temperature wouldn't raise above 60 degrees. Well anyways, about a week ago when I was driving, the check engine light came on and I used an OBD tool to confirm that it was the thermostat. I then ordered a part online, replaced the thermostat, and the operating temperature seems to be back to normal (80-90) even on warm days. The only problem that I am having now is that the check engine light still shows the code for P0128. I have tried clearing the code with an OBD tool as well as pulling negative and positive off the battery for 30 mins, but neither of those options worked. After that, I went back and check the two pigtails that were pulled off to make sure that they were making contact, as well as checked fluid level and hoses to see if anything was potentially leaking. There was no leak and all the connections and hoses seemed to be situated fine. I know the next thing that I would probably have to try would be to ohms test the coolant temperature sensor, but I shouldn't have to since it was a brand new part and it came as an entire assembly. Has anyone else had a similar problem? And if so how did you go about getting rid of the check engine light?
I'm going to attempt to change my thermostat did you follow a how to or video to change it? The videos I see on YouTube seem to be for models before 2013 is it much different like locations of the thermostat?
I'm going to attempt to change my thermostat did you follow a how to or video to change it? The videos I see on YouTube seem to be for models before 2013 is it much different like locations of the thermostat?
Replacement of the thermostat on the facelift C250 is significantly different from the earlier models. It is buried behind a mass of hoses and connections on the front of the engine. The first picture shows it location with everything in place and the second picture with the air intake hose removed. You can see where the upper radiator hose connects to the thermostat. One lesson I did learn is to remove the hose between the power steering reservoir and the top of the power steering pump. It makes the task much easier. Just remember to drain the reservoir first and be careful removing the end of the hose at the power steering pump as the hose is still full of fluid. I made the mistake of trying to work around this hose but ended up having to remove it it mid-task and managed to bathe the bottom half of the engine in power steering fluid.
Replacement of the thermostat on the facelift C250 is significantly different from the earlier models. It is buried behind a mass of hoses and connections on the front of the engine. The first picture shows it location with everything in place and the second picture with the air intake hose removed. You can see where the upper radiator hose connects to the thermostat. One lesson I did learn is to remove the hose between the power steering reservoir and the top of the power steering pump. It makes the task much easier. Just remember to drain the reservoir first and be careful removing the end of the hose at the power steering pump as the hose is still full of fluid. I made the mistake of trying to work around this hose but ended up having to remove it it mid-task and managed to bathe the bottom half of the engine in power steering fluid.
Great thank you for the tip I will replace the thermostat this Sunday. Happy Holidays!!!
05-31-2019, 04:03 PM
