Checking the fuel lines

• To expose the heater and access the fuel lines:
  • For cars manufactured up to w38 2001 inclusive, see Engine coolant heater, replacing
  • For cars manufactured from w39 2001 inclusive, see Engine coolant heater, replacing .

  Check the fuel lines for damage and leaks between their connection point to the engine fuel system and the heater via the fuel pump (FP).

  Check the fuel lines for blockages.

Was a fault detected? 

• YES 

  Refer to Verification 

• NO 

  Refer to Checking components