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Technician Safety Information




Safety Precautions


WARNING!
Fire hazard! Do not smoke, work near heaters or open flame, or have anything nearby that could ignite fuel. The fuel system is under pressure. Before opening, cover connections with a rag, and open carefully to release pressure. Be alert when working on or near the engine and ignition wires. High secondary ignition 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 starter if fuel injectors are removed

Be sure the ignition is switched OFF, when:
- Disconnecting or connecting the battery, ignition wires, or test equipment leads
- Disconnecting fuel injection system wiring
- Washing the engine or engine compartment

BEFORE cranking engine at starting RPM (eg. for compression testing) disable ignition and fuel injection systems:
- Disconnect both ignition coil power output stages, and both Motronic fuses at the E-box in the plenum.
- Disconnect harness connectors from all fuel injectors.
- Afterward, erase 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.