Mitsubishi Eclipse 1990 Service Manual page 641

Wave pattern observation points
Point: Condition of wave pattern build-up section and maximum voltage (Refer to abnormal wave pattern
examples 1 and 2.)
Condition of wave pattern build-up section and maximum voltage
Rises from approx.
to
rectangular wave
Rectangular wave at power voltage
--- Normal wave pattern
-- Normal wave pattern
approx. at the top-right
Examples of abnormal wave
Revision
Probable cause
Normal
Open-circuit in ignition primary circuit
Ignition power transistor malfunction
Example 1
Wave pattern during engine cranking
of problem
Open-circuit in ignition primary circuit
Wave pattern
Top-right part of the build-up section cannot
voltage value is approxiinatety
Example 2
Wave pattern during engine cranking
Cause of problem
Malfunction in ignition power transistor
Wave pattern characteristics
Power voltage results when the ignition power transistor
is ON.
, ,
too