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Oscilloscope Patterns and Waveforms




- Ignition coil primary signal
- Ignition power transistor control signal

MEASUREMENT METHOD
1. Disconnect the ignition power transistor connector, and connect the special tool (test harness: MB99l 348) in between. (All terminals should be connected.)
2. Connect the analyzer special patterns pickup to the ignition power transistor connector terminal 2 (No. 2 - No. 3) and terminal 7 (No. 1 - No. 4) respectively.

ALTERNATE METHOD (TEST HARNESS NOT AVAILABLE)
1. Connect the analyzer special patterns pickup to ECM terminal 10 and connection terminal 23 respectively.





STANDARD WAVE PATTERN (OBSERVATION CONDITIONS)
Function Special patterns
Pattern height Low
Pattern selector Display
Engine RPM Approx. 1,200 RPM