Safety precautions

To reduce the risk of personal injury and/or damage to the fuel injection and ignition system, always observe the following:

• Do not touch or pull off ignition wires when engine is running or turning at starting RPM.
• Always switch ignition off before disconnecting or reconnecting wires for the injection and ignition system, including high voltage wiring and test leads.
• If engine is to be cranked at starting RPM without starting (e.g. for compression testing), disconnect connector from ignition coils and from fuel injectors.
• It is possible that the control module will recognize a malfunction and store a DTC during some tests. After completing all tests and repairs, DTC memory should therefore be checked and erased if necessary. Readiness code must be generated after DTC memory is erased. See READINESS CODE, GENERATING .
• Always switch ignition off before cleaning engine.
• The battery should only be disconnected and reconnected when the ignition is turned off, since otherwise the Engine Control Module (ECM) can be damaged.