Temperature Sensor (Outside) - Testing
TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERSDATE: April 1990
REF.NO. MBNA 54/33
SUBJECT:
UNNECESSARY REPLACEMENT OF OUTSIDE TEMPERATURE SENSOR
ALL MODELS
Recent inspections of outside temperature sensors returned under warranty revealed that 40% were replaced unnecessarily.
Prior to replacing an outside temperature sensor, perform the following test procedure:
1. Measure resistance of sensor (B14) at connection to temperature gauge (see Data table for values).
2. If obtained resistance value agrees with specified value, check sensor wire for intermittent faults (flex the wire to check for faults).
3. If no faults are found, Do Not replace the temperature sensor.
4. Refer to Troubleshooting chart for further diagnosis.
Resistance Data
Sensor Temperature Resistance (Ohms)
32 °F (0 °C) 9800 +/- 100
68 °F (20 °C) 3750 +/- 70
104 °F (40 °C) 1600 +/- 40
