High Pressure Area Safety Precautions

High Pressure Area Safety Precautions

Special tools, testers and auxiliary items required
- Assembly tool T10118

Procedure

CAUTION:
The fuel injection system is divided into a high pressure section (maximum approximately 120 bar) and a low pressure system (approximately 6 bar):
- Before opening high pressure area - e.g. removing high pressure pump, fuel rail, fuel injectors, fuel lines or fuel pressure sensor G247 - fuel pressure in high pressure area must be reduced to a residual pressure of approximately 6 bar. The procedure for this is as follows.







- Remove electrical connector - 1 - from fuel pressure regulator valve N276 using assembly tool T10118.
- Allow engine to idle approximately 10 seconds.

NOTE:
- When fuel pressure regulator valve N276 electrical connector is disconnected during idle, pressure in high pressure area decreases to approximately 6 bar.
- After high pressure has been released, high pressure system must be opened, otherwise the pressure increases again due to the warming of the fuel.

- Switch off ignition.

CAUTION:
Fuel lines are pressurized.
- Wear protective goggles and protective clothing to prevent injuries and contact with skin.
- Before opening the high pressure system, place a cloth around the connection.

- Place a clean cloth around the connection point and carefully open to release the residual pressure of approximately 6 bar. Escaping fuel must be absorbed.

NOTE: By separating connections, DTCs are stored to memory. After assembling, check the fault memory and erase, if necessary.

- Check engine control module DTC memory and erase all DTC entries which may have occurred during the assembly "Guided Function".

NOTE: If DTC memory was erased, generate readiness code "Guided Function".