Test requirements:
- Fuses for engine electronics OK
See appropriate System Wiring Diagram article.
- Ground (GND) connections at engine and transmission OK
- Battery voltage at least 12.7 V
- Parking brake engaged.
- Vehicles with automatic transmission: Selector lever in position "P" or "N".
- Electrical consumers switched off (radiator fan must NOT run during test).
- A/C switched off.