Test Magneto Resistance
Ohm test fire coil
Check manufacture specs for resistance readings.Below are two examples.
Example 1
Single fire coil
Set meter to Ohms
Place probes in wires A and B
.32-.42 Ohms reading is satisfactory.
Below enlarged view
Shows start of coil winding (Green wire attaches here)
Example 2
Series double fire coils for single cylinder engine
Check coils as in first example.
read .49-.53 ok
read 0 bad
Test Trigger Coil
Disconnect trigger wireSet meter to continuity.
Attach a probe to the wire coming from the trigger coil.
Find a good ground for the other probe.
A field is created in the crankshaft position sensor when the flywheel magnet passes over it.
This pulse will show up as a meter bounce when the engine is turned over.
How to remove flywheel
