Component Location Overview - Injection System

Right Side of the Engine Compartment

1. E-box in Plenum Chamber
   • Engine Control Module -J623- with height sensor
   • Removing and installing. Refer to Engine Control Module -J623-, REMOVING AND INSTALLING .
2. Mass Airflow Sensor -G70-
   • Removing and installing. Refer to Mass Airflow Sensor -G70-, REMOVING AND INSTALLING .
3. Camshaft Position Sensor -G40-
   • Component location. Refer to Fig 6.
4. Fuel Temperature Sensor -G81-
   • Component location. Refer to Fig 7.
5. Engine Coolant Temperature Sensor -G62-
   • Component location. Refer to Fig 4.
   • Removing and installing. Refer to Engine Coolant Temperature Sensor -G62-, REMOVING AND INSTALLING .
6. 6 - Bracket to Plenum Chamber Bulkhead
   • Differential Pressure Sensor -G505- - adapt after replacing
   • Exhaust Gas Temperature Sensor 2 -G448- connector (engine code CATA)
   • Heated Oxygen Sensor -G39- connector with Oxygen Sensor Heater -Z19-
   • Exhaust Gas Temperature Sensor 4 -G648- connector
   • Component location. Refer to Fig 19.
7. Fuel Pressure Regulator Valve -N276-
   • Component location. Refer to Fig 6.
   • Cannot be used again
   • The adaptation values must be adapted after replacing the high pressure pump or the Fuel Pressure Regulator Valve -N276-. Refer to "Guided Functions" using the Vehicle Diagnostic Tester.
   • Removing and installing. Refer to Fuel Pressure Regulator Valve -N276-, REMOVING AND INSTALLING .
8. EGR Temperature Sensor -G98- Connector
   • Component location. Refer to Fig 8.
9. Exhaust Gas Temperature Sensor 1 -G235- Connector
   • Component location. Refer to Fig 8.
10. Turbocharger 1 Control Module -J724-
    • Removing and installing. Refer to Turbocharger Control Module 1 -J724-, REMOVING AND INSTALLING .
11. Intake Flap Motor -V157-
    • Cylinder bank 1
    • Intake manifold overview. Refer to OVERVIEW - INTAKE MANIFOLD .
12. Fuel High Pressure Pump
    • Component location. Refer to Fig 15.
    • High pressure pump overview. Refer to OVERVIEW - HIGH PRESSURE PUMP .
    • Removing and installing. Refer to HIGH PRESSURE PUMP, REMOVING AND INSTALLING .
13. Fuel Metering Valve -N290-
    • Component location. Refer to Fig 15.
14. Reduced Oil Pressure Switch -F378-
    • Component locations. Refer to Fig 11
    • Removing and installing. Refer to REDUCED OIL PRESSURE SWITCH -F378-, REMOVING AND INSTALLING .
15. EGR Cooler Pump -V400-
    • Component location. Refer to Fig 10.
16. Pressure Retaining Valve or Restrictor in the Fuel Return Line
    • Component location. Refer to Fig 7.
    • The type of component that was installed is dependent upon the model year
    • The check valve always maintains a residual pressure (control quantity) of approximately 10 bar (145 psi) in the fuel return lines.
    • The restrictor always maintains a residual pressure (control quantity) of approximately 4 bar (58 psi) in the fuel return lines.
    • The Piezoelectric injectors need this control quantity for their function.
    • The check valve or the restrictor can be replaced only with the complete fuel return lines.
    • Bleed the fuel system after replacing. Refer to FUEL TANK, FILLING WITH FUEL AFTER INSTALLING HIGH PRESSURE PUMP 
    • Check pressure retaining valve. Refer to FUEL RETURN CHECK VALVE, CHECKING 
    • Check the restrictor. Refer to RESTRICTOR IN THE FUEL RETURN LINE, CHECKING 
17. Injector
    • Cylinder bank 1
    • Removing and installing. Refer to PIEZOELECTRIC FUEL INJECTORS, REMOVING AND INSTALLING .
18. Engine Coolant Temperature Sensor on Radiator Outlet -G83-
    • Component location. Refer to Fig 3.

Left Side of the Engine Compartment

Component A through N are not shown in the exploded view.

1. Fuel High Pressure Pump
   • With Fuel Metering Valve -N290-
   • Component location. Refer to Fig 15.
   • High pressure pump overview. Refer to OVERVIEW - HIGH PRESSURE PUMP .
   • Removing and installing. Refer to HIGH PRESSURE PUMP, REMOVING AND INSTALLING .
2. EGR Motor -V338-
   • Component location. Refer to Fig 8.
3. EGR Cooler Switch-Over Valve -N345-
   • Component location. Refer to Fig 8.
   • EGR Cooler Switch-Over Valve 2 -N381- installation location. Refer to Fig 9
   • Removing and installing. Refer to EGR COOLER, REMOVING AND INSTALLING .
4. EGR Temperature Sensor -G98-
   • Component location. Refer to Fig 8.
   • Removing and installing. Refer to EGR Temperature Sensor -G98-, REMOVING AND INSTALLING .
5. Intake Flap Motor 2 -V275-
   • Cylinder bank 2
   • Intake manifold overview. Refer to Engine Control Module -J623-, REMOVING AND INSTALLING .
6. Installation Location Inside the Exhaust System
   • Heated Oxygen Sensor -G39- with Oxygen Sensor Heater -Z19-
   • NOx Sensor -G295-
   • Exhaust Gas Temperature Sensor 2 -G448- (engine code CATA)
   • Catalyst Temperature Sensor 1 -G20- (engine code CATA, not installed in all vehicles)
   • Exhaust Gas Temperature Sensor 3 -G495-
   • Component locations. Refer to Fig 17
7. Catalyst Temperature Sensor 1 -G20- Connector
   • Installed only on vehicles with engine code CATA
   • Component location. Refer to Fig 18.
8. Exhaust Gas Temperature Sensor 3 -G495- Connector
   • Component location. Refer to Fig 18.
9. Auxiliary Fuel Pump -V393-
   • The Auxiliary Fuel Pump -V393- is discontinued starting with MY 2011.
   • Component location. Refer to Fig 5.
   • Removing and installing. Refer to Auxiliary Fuel Pump - V393-, REMOVING AND INSTALLING .
10. Fuel Cooler
    • Removing and installing. Refer to FUEL COOLER, REMOVING AND INSTALLING .
11. Fuel Filter
    • Removing and installing. Refer to FUEL FILTER .
12. NOx Sensor -G295-
    • NOx Sensor -G295- installation location. Refer to Fig 17
    • Connector. Refer to Fig 21
    • Removing and installing. Refer to NOx Sensor -G295-, REMOVING AND INSTALLING .
13. Throttle Valve Control Module -J338-
14. Injection units (Piezoelectric injectors)
    • Cylinder bank 2
    • Removing and installing. Refer to PIEZOELECTRIC FUEL INJECTORS, REMOVING AND INSTALLING .
15. Charge Air Pressure Sensor -G31- with Intake Air Temperature Sensor -G42-
    • Component locations. Refer to Fig 16
    • Removing and installing. Refer to Charge Air Pressure Sensor -G31-, REMOVING AND INSTALLING .
16. Fuel Pressure Sensor -G247-
    • With biting edge for sealing
    • Cannot be used again
    • Component location. Refer to Fig 13.
    • Removing and installing. Refer to Fuel Pressure Sensor -G247-, REMOVING AND INSTALLING .
17. Oil Pressure Control
    • Oil Pressure Switch -F22-
    • Oil Pressure Regulation Valve -N428-
    • Component locations. Refer to Fig 12
    • Removing and installing. Refer to OIL PRESSURE SWITCH -F22-, REMOVING AND INSTALLING .
    1. Brake Lamp Switch -F- and Brake Pedal Switch -F47-
       • In footwell at brake pedal
    2. Accelerator Pedal Position Sensor -G79- and Accelerator Pedal Position Sensor 2 -G185-
       • In footwell, at accelerator pedal
       • After replacing, the kick-down switch on vehicles with automatic transmission must be re-adapted.
       • Adapting the kick-down, see Guided Fault Finding.
    3. Starter Relay -J53- and Relay 2 for Starter -J695-
       • Component locations. Refer to the appropriate Wiring Diagram
    4. Automatic Glow Time Control Module -J179-
       • Component locations. Refer to the appropriate Wiring Diagram
    5. Terminal 30 Power Supply Relay -J317-
       • Component locations. Refer to the appropriate Wiring Diagram
    6. Terminal 15 Power Supply Relay -J329-
       • Component locations. Refer to the appropriate Wiring Diagram
    7. Engine Speed Sensor -G28-
       • In the transmission housing above the starter ring gear
       • Connector installation locations. Refer to Fig 14
    8. Glow Plugs
       • Glow Plug 1 -Q10-
       • Glow plug 2 -Q11- with Cylinder 2 Combustion Chamber Pressure Sensor -G678- (single component)
       • Glow Plug 3 -Q12-
       • Glow Plug 4 -Q13-
       • Glow plug 5 -Q14- with Cylinder 5 Combustion Chamber Pressure Sensor -G681- (single component)
       • Glow Plug 6 -Q15-
       • Removing and installing. Refer to GLOW PLUGS, REMOVING AND INSTALLING .
    9. Exhaust Gas Temperature Sensor 1 -G235-
       • Install on the turbocharger. Refer to Fig 23
       • Electrical harness connector. Refer to Fig 8
       • Removing and installing. Refer to Exhaust Gas Temperature Sensor 1 -G235-, REMOVING AND INSTALLING .
    10. Exhaust Gas Temperature Sensor 4 -G648-
        • Component location. Refer to Fig 20.
        • Removing and installing. Refer to EXHAUST TEMPERATURE CONTROL OVERVIEW .
    11. NOx Sensor 2 -G687-
        • Removing and installing. Refer to NOx Sensor 2 -G687-, REMOVING AND INSTALLING .
    12. Reducing Agent Injector -N474-
        • Component location. Refer to Fig 22.
        • Removing and installing. Refer to Reducing Agent Injector -N474-, REMOVING AND INSTALLING .
    13. Fuel Pump Control Module -J538-
        • Only on vehicles from MY 2011
    14. Particulate Filter
        • Installed on the underbody
        • Shared component with a catalytic converter
        • After replacing the particulate filter, perform an adaptation on the engine control module
        • Removing and installing. Refer to PARTICULATE FILTER, REMOVING AND INSTALLING .

An adaptation must be performed after replacing the Differential Pressure Sensor -G505- and/or particulate filter.

1 - Auxiliary Fuel Pump -V393-

2 - Auxiliary Fuel Pump -V393- connector

3 - Fuel supply line via the Auxiliary Fuel Pump -V393- to the high pressure fuel pump

4 - Fuel return line to the fuel cooler

5 - Fuel cooler

6 - Fuel filter

7 - Fuel supply line from the fuel tank

8 - Fuel return line from the high pressure pump

9 - Fuel return line to the fuel tank

1 - Camshaft Position Sensor -G40-

2 - Fuel Pressure Regulator Valve -N276-

1 - Fuel Pressure Regulator Valve -N276-

2 - Fuel Temperature Sensor -G81-

3 - Pressure retaining valve or restrictor in the fuel return line

1 - EGR Temperature Sensor -G98- connector

2 - Exhaust Gas Temperature Sensor 1 -G235- connector

3 - Not installed in this location

4 - EGR Cooler Switch-Over Valve -N345-

5 - EGR Temperature Sensor -G98-

6 - EGR Motor -V338-

• Removing and installing. Refer to OIL PRESSURE SWITCH -F22-, REMOVING AND INSTALLING .

1 - Oil Pressure Switch -F22-

2 - Oil Pressure Regulation Valve -N428-

1 - Fuel supply line to the high pressure pump

2 - Fuel return line to the fuel tank

3 - High pressure fuel line to fuel rail (cylinder bank 1)

4 - High pressure pump, removing and installing. Refer to HIGH PRESSURE PUMP, REMOVING AND INSTALLING .

5 - Fuel Metering Valve -N290-

1 - Exhaust Gas Temperature Sensor 3 -G495-

2 - Catalyst Temperature Sensor 1 -G20- (engine code CATA, not installed in all vehicles)

3 - Exhaust Gas Temperature Sensor 2 -G448- (engine code CATA)

4 - NOx Sensor -G295-

5 - Heated Oxygen Sensor -G39- with Oxygen Sensor Heater -Z19-, Removing and installing. Refer to Heated Oxygen Sensor -G39- WITH Oxygen Sensor Heater -Z19-, REMOVING AND INSTALLING .

1 - For the Catalyst Temperature Sensor 1 -G20- (engine code CATA)

2 - For the Exhaust Gas Temperature Sensor 3 -G495-

1 - Exhaust Gas Temperature Sensor 2 -G448- connector (engine code CATA)

2 - Heated Oxygen Sensor -G39- connector with Oxygen Sensor Heater -Z19-

3 - Differential Pressure Sensor -G505-

4 - Exhaust Gas Temperature Sensor 4 -G648- connector

1 - NOx Sensor -G295- connector