General Safety Guidelines
WARNING:Be alert when working on or near the engine. High ignition secondary voltage can cause serious personal injury and damage vehicle components.
- DO NOT touch or disconnect ignition system wires when the engine is running or being cranked at starting RPM.
- DO NOT operate the starter if the fuel injectors have been removed.
Be sure the ignition is switched OFF, when:
- Disconnecting ignition wires
- Disconnecting fuel injection system wiring
- Connecting or disconnecting test equipment leads
- Disconnecting the battery
- Washing the engine or engine compartment
BEFORE cranking the engine at starting RPM (such as for compression testing) disable the ignition and fuel injection systems:
- Disconnect the ignition coil power output stage.
- Disconnect harness connectors from all fuel injectors.
- After the work is completed, clear Diagnostic Trouble Code (DTC) memory.
CAUTION:
BEFORE disconnecting the battery:
- Stop the engine.
- Be sure the ignition is switched OFF (also applies when connecting the battery). Failure to do so may damage the Engine Control Module (ECM).
- Be sure of the proper radio code (for vehicles equipped with coded anti-theft radio).
Be sure the battery negative (-) cable is disconnected, when:
- Working on the electrical system
- Resistance (spot) welding or electric arc welding anywhere on the vehicle.
When connecting and disconnecting electrical test equipment (LED voltage tester, multimeter, etc.):
- Be sure the ignition is switched OFF
- Use correct adapters from the VW 1594 connector test kit For any work affecting the Engine Control Module (ECM):
- BEFORE disconnecting the ECM harness connector, switch the ignition OFF and WAIT at least 20 seconds. Failure to do so may damage the ECM.
- DO NOT connect any outside voltage source to stimulate an output signal at the ECM.
To prevent damage to electronic components, switch multimeter to correct measuring range before connecting the adapter cable. Observe test conditions and carry out additional work listed in the table.