Suzuki Engine 2002 GRAND VITARA SQ625, Service Manual

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6F2-6 IGNITION SYSTEM (FOR J20/H25 ENGINES)
Reference
J20 engine
Oscilloscope waveforms of CMP sensor and No.1 ignition trigger
signal are as shown in figure when connecting oscilloscope
between terminals C51-2-26 and C51-3-26 of ECM (PCM) con-
nectors connected to ECM (PCM), and between terminal C51-2-
24 and ground.
H25 engine
Oscilloscope waveforms of CMP sensor REF signal and No.1
ignition trigger signal are as shown in figure when connecting
oscilloscope between terminal C51-3-10 of ECM (PCM) connec-
tor connected to ECM (PCM) and ground, and between terminal
C51-2-13 and ground.
7 CMP Sensor Check
1) Check CMP sensor.
Refer to Step 6 or 7 of DTC P0340 Diag.
Flow Table in Section 6 or 6-1.
Is check result satisfactory?
Substitute a known-good
ECM (or PCM) and then
repeat Step 2. Tighten CMP sensor bolt
or replace CMP sensor.
8 Ignition Timing Check
1) Check initial ignition timing and ignition tim-
ing advance, referring to “Ignition Timing
Check And Adjustment” in this section.
Is check result satisfactory?
System is in good condi-
tion. Adjust ignition timing or
check ECM (PCM) input
signals related to this sys-
tem.
Step Action Yes No
[A] : Oscilloscope waveforms at specified idle speed
[B] : J20 engine model
[C] : H25 engine model
1. CMP sensor
2. No.1 ignition trigger signal
3. Primary coil current flow time
4. REF signal of CMP sensor