Coolant thermostat - fault code description, ME-SFI - AD07.61-P-4000-76M

		Coolant thermostat
1	Fault code (Fault code according to OBD)	P202C (P0128)
2	Fault storage	After expiry of test duration and fault
	Actuation of the engine diagnosis indicator lamp (EURO4) or CHECK ENGINE (MIL)	no activation Following two successive driving cycles with faults
3	Checking frequency	After the cold start
4	Checked signal or status	The increase in temperature after a cold start is compared to a stored temperature model.
5	Fault setting conditions	Coolant temperature less than +75°C, although it must be well above +86°C according to the temperature model.
	Checking duration	10 to 30 min
6	Check prerequisites	Lambda control enabled Coolant temperature at engine start less than +65°C Coolant temperature at engine start greater than -10°C Intake air temperature higher than -10°C No coolant temperature sensor fault or charge air temperature sensor fault Stationary heater off Travel at maximum 46 % idle speed and maximum 12% overrun fuel shutoff.