2010 Mercedes Benz C 300 (204.054) V6-3.0L (272.947) Page 996

- Read fault memory from control unit ESP and rectify faults.

End of test

1461

B11/4 (Coolant temperature sensor) : Coolant temperature is too high. (P0116)

Possible cause:

- B11/4 (Coolant temperature sensor)

- Y110 (Three-disk thermostat valve)

- The cooling performance of the engine cooling system is poor.

Affected functions:

- Engine diagnosis

- Engine cooling

-------------------------------------------------

Test 1: The cooling performance of the engine cooling system is poor.

Test 2: Check component B11/4 (Coolant temperature sensor).

Test 3: Check component Y110 (Three-disk thermostat valve).

1. The cooling performance of the engine cooling system is poor.

The cooling performance of the engine cooling system is poor.

2. Check component B11/4 (Coolant temperature sensor).

Test 2.1: Check component B11/4 (Coolant temperature sensor) using actual value.

Test 2.2: Check signal lines on component B11/4 (Coolant temperature sensor).

Test 2.3: Check internal resistance of component B11/4 (Coolant temperature sensor).

2.1. Check component B11/4 (Coolant temperature sensor) using actual value.

Test prerequisite

- The actual value is not o.k.

Test sequence

- Switch on ignition.

Status of relevant actual value:

- Coolant temperature:Warning! Communication with ECU required.

- Coolant temperature sensor ( Signal voltage ):Warning! Communication with ECU required.

Specified values

- Voltage[20锟斤拷 C]: [3.45...3.32] V

- Voltage[30锟斤拷 C]: [2.93...2.82] V

- Voltage[40锟斤拷 C]: [2.41...2.32] V

- Voltage[50锟斤拷 C]: [1.93...1.86] V

- Voltage[60锟斤拷 C]: [1.51...1.46] V

- Voltage[70锟斤拷 C]: [1.18...1.13] V

- Voltage[80锟斤拷 C]: [0.90...0.87] V

- Voltage[90锟斤拷 C]: [0.70...0.67] V

- Voltage[100锟斤拷 C]: [0.54...0.25] V

- Voltage[110锟斤拷 C]: [0.42...0.40] V

Question

- Are the measurement values OK?

YES

The measurement values are OK.End of test

NO

The measurement values are not OK.Possible cause and remedy