General Notes on Fuel Injection

General Notes On Fuel Injection
- The Engine Control Module (ECM) is equipped with an On Board Diagnostic (OBD) Always check the DTC memories of all control modules via the automatic test sequence before performing repairs or troubleshooting. This is necessary because different control modules are connected to each other via the CAN-bus. Vacuum hoses and connections should also be checked (unmetered air).
- Fuel hoses in engine compartment may only be secured with spring-type clamps. The use of clamping collars or screw clamps is not permitted.
- Always switch off ignition before disconnecting battery Ground (GND) strap. If a coded radio is installed, obtain code before disconnecting battery.
- Components marked with * are checked via On Board Diagnostic (OBD).
- Components marked with ** can be checked via output Diagnostic Test Mode (DTM).
- For the electric components to work properly, a voltage of at least 11.5 V is required.
- Do not use any silicone sealant. Traces of silicone components which are sucked into the engine are not burned there, and they damage the oxygen sensor.
- If the engine only starts briefly and then turns off again after troubleshooting, repair or checking of the components, it may be that the immobilizer is blocking the Engine Control Module (ECM). DTC memory must then be checked and if necessary, control module must be adapted.
- It is possible that the control module will recognize a malfunction and store a DTC during some tests. Therefore, after all tests and repairs have been performed, DTC memory should be checked and erased if necessary.
- Airbag-equipped vehicles have a fuel crash shut-off This is intended to reduce the risk of vehicle fire following a crash by switching off the Fuel Pump (FP) via the Fuel Pump (FP) relay.
- When the driver-side door is opened, the Fuel Pump (FP) is activated for 2 seconds so that pressure builds in the fuel system. This ensures a more comfortable start behavior.