125 Oil Temperature Sensor - Below Limit
P0197
125 Oil Temperature Sensor - Below Limit
Function
The temperature sensor measures the oil temperature via a variable resistor. The oil temperature is used to control camshaft adjustment.
Diagnosis conditions
- Engine running
NOTE: A substitute value of 20 °C is used in the event of a malfunction of the temperature sensor.
P0197 - P0198:
Wiring Diagram
Resistance values
60 °C : 2.8 - 3.5 k ohms
90 °C : 1.0 - 1.3 k ohms
120 °C : 0.4 - 0.6 k ohms
Diagnosis Procedure
1 Check temperature sensor.
1. Connect special tool 9637 to wiring harness (DME control module connector).
2. Connect ohmmeter to pins III/17 and III/5.
Display: 2.8 - 3.5 k ohms at 60 °C
2 Check wiring from DME control module to temperature sensor for continuity.
1. Connect special tool 9637 to wiring harness (DME control module connector).
2. Remove connector of temperature sensor.
3. Connect ohmmeter to pin III/17 (special tool 9637) and pin 3 (temperature sensor connector).
Display: 0 - 5 ohms
4. Connect ohmmeter to pin III/5 (special tool 9637) and pin 1 (temperature sensor connector).
Display: 0 - 5 ohms
3 Check wiring from DME control module to temperature sensor for short to ground.
1. Connect special tool 9637 to wiring harness (DME control module connector).
2. Remove connector of temperature sensor.
3. Connect ohmmeter to pin III/5 and ground.
Display: infinity ohms
If 0 - 5 ohms is displayed, check wiring harness for chafing and pinching damage.
4 Perform adaptation.
1. Switch on the ignition.
2. Wait one minute. Do not press the accelerator.
3. Switch off the ignition for at least 10 seconds.
4. Read out the fault memory.
5 Check wiring from DME control module to temperature sensor for short to B+.
1. Connect special tool 9637 to wiring harness (DME control module connector).
2. Remove connector of temperature sensor.
3. Connect voltmeter to pin III/5 and ground. Switch on the ignition.
Display: 0 V
If battery voltage is displayed, check wiring harness for chafing and pinching damage.