Checking the Primary Ignition Circuit in Conventional Ignition Systems

To check, you must use a universal measuring device. Connect and disconnect the device only with the ignition off.



SEQUENCE OF WORK

1. The primary winding of the ignition coil is energized at the contact «15» / «+». Through the primary winding, voltage is supplied from the contact «4» to the power module in the control unit. Ignition voltage (approx. 30,000 V / 30 kV) is fed through high-voltage wires from the ignition coil to the ignition distributor and there «distributed» to the spark plugs of the respective cylinders.

2. To measure voltage, connect a measuring device between the contact «15» / «+» and contact «masses». The voltage supply from the battery is good if there is a constant voltage of at least 11.5 V. If the measured voltage is lower or not at all, the following reasons are possible:

• breakage of the control wire to the ignition switch;
• faulty ignition switch (as a rule, in this case, the starter does not work either);
• an open in the connection between the ignition switch and the universal electrical connector.