Differential Pressure Sensor -G505-, CHECKING

Function

Exhaust Gas Temperature Sensors are positive temperature coefficient (PTC) sensors. They measure the temperature of the exhaust gas. The ECM uses the signals from Exhaust Gas Temperature Sensors to calculate the amount of contamination in the diesel particulate filter, also to protect the turbocharger from unacceptably high exhaust gas temperatures. The diesel particulate filter contamination status is calculated using these signals from the Exhaust Gas Temperature Sensors, together with the signals from; Exhaust Pressure Sensor 1 -G450-, Differential Pressure Sensor -G505-, Exhaust Pressure Sensor 2 -G451-, Mass Airflow Sensor -G70-, and Heated Oxygen Sensor -G39-. The signal also serves as component protection in order to protect the diesel particulate filter and turbocharger from excessively high exhaust gas temperatures.

Special tools and workshop equipment required 

• Multimeter
• Wiring Diagram
• Scan Tool

Test Requirements 

• Fuses OK
• Battery voltage OK
• Switch OFF all electrical and electronic accessories
• Vehicles with Auto. Transmission, ensure Selector Lever position is in "P".
• Vehicles with Man. Transmission, ensure Shifter Lever position is in "N" with Parking Brake applied
• Coolant Temperature: ≥ 80 °C
• Observe all safety precautions: SAFETY PRECAUTIONS 

Test Procedure