LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 1999 >> C43 >> Repair and Diagnosis >> External Pages >> Different car >> Section 35 (Manual A/C-Heater Systems - Ml 320, Ml 430 & Ml 55) >> System Tests >> Electrical Tests >> In-Vehicle Temperature Sensor

In-Vehicle Temperature Sensor

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2001 Mercedes-Benz ML55, 2001 Mercedes-Benz ML430, 2001 Mercedes-Benz ML320, 2000 Mercedes-Benz ML55, and 2000 Mercedes-Benz ML430. However, it is still accessible from the selected car via links, so may be relevant.
  1. Connect socket box to A/C push button control unit and wiring harness. See CONNECTING TEST EQUIPMENT  . Connect voltmeter positive lead to socket box terminal No. 12 and negative lead to terminal No. 9.
  2. Turn ignition on. Turn temperature control knob to Red range detent. Voltage should be 1.9 volts at 68°F (20°C). If voltage is as specified, go to next step. If voltage is not as specified, check in-vehicle temperature sensor circuits. See WIRING DIAGRAMS  . Repair as necessary. If circuits are okay, replace in-vehicle temperature sensor.
  3. Turn ignition off. Disconnect test cable from A/C push button control unit. Connect ohmmeter positive lead to socket box terminal No. 2 and negative lead to terminal No. 12. Measure temperature sensor resistance at specified temperatures. See IN-VEHICLE TEMPERATURE SENSOR RESISTANCE  table.
  4. If resistance is not as specified, check wiring harness and connectors between A/C push button control unit, in-vehicle temperature sensor, blend air flap actuator position sensor and temperature regulator switch. Repair as necessary.
IN-VEHICLE TEMPERATURE SENSOR RESISTANCE

Sensor Temperature - °F (°C) Ohms
68 (20) 2100
77 (25) 1700
104 (40) 900
scientia non olet · About LEMON Manuals