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 signal lines on component B11/4 (Coolant temperature sensor).
Test 2.2: Check internal resistance of component B11/4 (Coolant temperature sensor).
Test 2.3: Check component B11/4 (Coolant temperature sensor) using actual value.
2.1. Check signal lines on component B11/4 (Coolant temperature sensor).
Test sequence
- Switch on ignition.
Status of relevant actual value:
- Coolant temperature sensor ( Signal voltage ):Warning! Communication with ECU required.
Specified value
- If the connection is unplugged at component B11/4 (Coolant temperature sensor), the value is approx. 5 V.
- Bridge pin 1 in pin 2 at the unplugged connection of component B11/4 (Coolant temperature sensor).The value is< 0.5 V.
Question
- Is the actual value o.k.?
YES
The actual value is okay.Further possible causes of fault
- Check internal resistance of component B11/4 (Coolant temperature sensor).
NO
The actual value is not o.k.Possible cause and remedy
- Check lines from component B11/4 (Coolant temperature sensor) to component N3/10 (ME-SFI [ME] control unit).
End of test
2.2. Check internal resistance of component B11/4 (Coolant temperature sensor).
Test prerequisite
- The actual value is not o.k.
Test sequence
- Switch off ignition.
- Disconnect connector at component B11/4 (Coolant temperature sensor).
- Measure resistance with multimeter between pins ( B11/4 ) 1 and ( B11/4 ) 2
Specified values
- Resistor(20锟斤拷 C): [3030...3130]ohms
- Resistor(30锟斤拷 C]: [1950...2050]ohms
- Resistor(40锟斤拷 C): [1275...1375]ohms
- Resistor(50锟斤拷 C): [850...950]ohms
- Resistor(60锟斤拷 C): [600...650]ohms
- Resistor(70锟斤拷 C): [420...460]ohms
- Resistor(80锟斤拷 C): [305...335]ohms
- Resistor(90锟斤拷 C): [220...240]ohms
- Resistor(100锟斤拷 C): [160...180]ohms
- Resistor(110锟斤拷 C): [120...140]ohms
Question
- Are the measurement values OK?
