How to test each sensor and wiring harness of common rail diesel engine?

The role of the diesel engine common rail high pressure sensor can greatly reduce the change of the diesel engine fuel supply pressure with the engine speed, thus reducing the defects of the traditional diesel engine. As the country has become more and more strict with the emission of diesel engines, electronically controlled high-pressure common rail diesel engines are increasingly used in agricultural machinery. So how to test each sensor and wiring harness of common rail diesel engine?

 

The relevant functions of each sensor of the common rail diesel engine and the response after failure are as follows:

 

Function: Provide the pressure in the common rail pipe, which is one of the most critical sensors in the common rail system.

 

After the failure, the system responds: the pressure limiting valve is opened, the return oil heats up, and it limps home.

 

1. Coolant temperature sensor

Function: Provide coolant temperature, which is related to intake air heating state and thermal protection function.

System response after failure: limp home

 

2. Oil pressure temperature sensor

Function: Provide oil pressure and temperature parameters

System response after failure: oil pressure alarm

 

3. Intake pressure temperature sensor

Function: Provide intake pressure and temperature parameters

System response after failure: diesel engine emits black smoke, white smoke, and limps home

 

4. Crankshaft speed sensor

Function: Provide crankshaft position signal, speed signal

System response after failure: difficult to start, smoke

 

5. Camshaft speed sensor

Function: Provide cylinder judgment signal and speed signal

System response after failure: start difficult, limp home

The function of each sensor of common rail diesel engine and its response after failure are as above.