0858
B11/4 (Coolant temperature sensor) : Short circuit to positive / Open circuit (P0117)
Possible cause:
- B11/4 (Coolant temperature sensor)
Affected functions:
- Engine cooling
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Test 1: Check component B11/4 (Coolant temperature sensor).
1. Check component B11/4 (Coolant temperature sensor).
Test 1.1: Check component B11/4 (Coolant temperature sensor) using actual value.
Test 1.2: Check signal lines on component B11/4 (Coolant temperature sensor).
Test 1.3: Check internal resistance of component B11/4 (Coolant temperature sensor).
1.1. 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° C]: [3.45...3.32] V
- Voltage[30° C]: [2.93...2.82] V
- Voltage[40° C]: [2.41...2.32] V
- Voltage[50° C]: [1.93...1.86] V
- Voltage[60° C]: [1.51...1.46] V
- Voltage[70° C]: [1.18...1.13] V
- Voltage[80° C]: [0.90...0.87] V
- Voltage[90° C]: [0.70...0.67] V
- Voltage[100° C]: [0.54...0.25] V
- Voltage[110° 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
- Line from component B11/4 (Coolant temperature sensor) to component N3/10 (ME-SFI [ME] control unit)
- B11/4 (Coolant temperature sensor)
End of test
1.2. 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
1.3. 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° C): [3030...3130]ohms
- Resistor(30° C]: [1950...2050]ohms
- Resistor(40° C): [1275...1375]ohms
- Resistor(50° C): [850...950]ohms
- Resistor(60° C): [600...650]ohms
- Resistor(70° C): [420...460]ohms
- Resistor(80° C): [305...335]ohms
- Resistor(90° C): [220...240]ohms
- Resistor(100° C): [160...180]ohms
- Resistor(110° C): [120...140]ohms
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
- B11/4 (Coolant temperature sensor)
End of test