Cooling fan won't turn off - Code P0128
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2011 E350 Coupe
Cooling fan won't turn off - Code P0128
I have a 2011 E350 Coupe with 129,000km
Last spring I had engine code P0128 come up. Took it to my mechanic, everything looked fine so he just cleared it and said come back if it lights up again. 3 months later I had the same code come up, cleared it and didn't see it again for a few months.
A couple of weeks ago I noticed my cooling fan was running more than normal. Shortly after P0128 came back. At that point I had the coolant thermostat changed as that seemed likely to be the issue, however that did not solve the problem, the fan still runs too much. The code has not come back yet. I left without the mechanic figuring out what the issue still was because it was end of day and we were waiting for other unrelated parts anyway. I'm going back tomorrow and want to see if anyone else has had this issue and can point to what it could be.
Some things I've noticed that might point to something more specific:
- If the ambient temperature is below ~10C (50F), fan seems to run normally and engine gets to temperature as normal
- If the ambient temperature is above ~10C (50F), fan will run too loud
- If the ambient temperature is above ~15C (60F), fan will be screaming and the engine will take too long to heat up. At highway speeds the coolant temp will also actually fluctuate between ~80-90 quite frequently.
A couple of other issues I'm getting fixed that I don't think are related but mentioning just in case:
- Intake manifold lever that controls the flaps is broken so I'm getting that replaced
- There is a squeak when turning left and sometimes when idling that sounds like a bearing on an accessory pulley or something is on its way out. Not sure though could be wrong.
Thanks for any help..
Last spring I had engine code P0128 come up. Took it to my mechanic, everything looked fine so he just cleared it and said come back if it lights up again. 3 months later I had the same code come up, cleared it and didn't see it again for a few months.
A couple of weeks ago I noticed my cooling fan was running more than normal. Shortly after P0128 came back. At that point I had the coolant thermostat changed as that seemed likely to be the issue, however that did not solve the problem, the fan still runs too much. The code has not come back yet. I left without the mechanic figuring out what the issue still was because it was end of day and we were waiting for other unrelated parts anyway. I'm going back tomorrow and want to see if anyone else has had this issue and can point to what it could be.
Some things I've noticed that might point to something more specific:
- If the ambient temperature is below ~10C (50F), fan seems to run normally and engine gets to temperature as normal
- If the ambient temperature is above ~10C (50F), fan will run too loud
- If the ambient temperature is above ~15C (60F), fan will be screaming and the engine will take too long to heat up. At highway speeds the coolant temp will also actually fluctuate between ~80-90 quite frequently.
A couple of other issues I'm getting fixed that I don't think are related but mentioning just in case:
- Intake manifold lever that controls the flaps is broken so I'm getting that replaced
- There is a squeak when turning left and sometimes when idling that sounds like a bearing on an accessory pulley or something is on its way out. Not sure though could be wrong.
Thanks for any help..
Last edited by MSTRMOO; Nov 6, 2018 at 04:04 PM.
