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Exhaust Temperature Sensor: Description and Operation




GF14.40-D-3016HU Component Description For Temperature Sensor Upstream of SCR Catalytic Converter

- with CODE (MG5) Engine OM 642 DE 30 LA, 140 kW (190 hp) 3800 rpm
- with CODE (MH1) Low-emission engine EPA 10/CARB
- with CODE (ZU7) National version for Canada

- with CODE (MG5) Engine OM 642 DE 30 LA, 140 kW (190 hp) 3800 rpm
- with CODE (MH1) Low-emission engine EPA 10/CARB
- with CODE (ZU8) National version for USA





Location

4 Selective Catalytic Reduction (SCR) catalytic converter

B16/12 Temperature sensor upstream of SCR catalytic converter

The temperature sensor upstream of the SCR catalytic converter is located in the exhaust system upstream of the SCR catalytic converter.

Task

The temperature sensor upstream of the SCR catalytic converter detects the current exhaust temperature upstream of the SCR catalytic converter.

Body

The temperature sensor upstream of SCR catalytic converter consists of a metallic housing with a positive temperature coefficient (PTC) precision resistor.

Function

The installed PTC precision resistor changes its electrical resistance according to the exhaust temperature. The electrical resistance increases as temperature increases.

The change in resistance results in a voltage signal, which is used by the CDI control unit (N3/30) to compute the exhaust temperature.