Ignition system

A check for cylinder leakage (also called "leak down") can be carried out instead of a compression test. Cylinder leakage test

Fig 1: Identifying Low & High Voltage Circuit Caution

Courtesy of VOLVO CARS OF NORTH AMERICA.

CAUTION:

The ignition system operates at high ignition charges and produces dangerous voltages in both the low and high voltage circuits.

There is dangerous voltage throughout the entire ignition system including connectors etc.