Suzuki 2000 Grand Vitara SQ416, Service Manual

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YH4
GRAND
VITARA
6F2-4 IGNITION SYSTEM (FOR J20 / H25 ENGINES)
DIAGNOSIS
Condition Possible Cause Correction
Engine cranks, but will not
start or hard to start No spark
Blown fuse for ignition coil assembly
Loose connection or disconnection of lead
wire
Faulty spark plug(s)
Faulty ignition coil assembly(s)
Faulty CMP sensor
Faulty ECM (or PCM)
Maladjusted ignition timing
Replace
Connect securely
Adjust, clean or replace
Replace
Replace
Replace
Adjust
Poor fuel economy or engine
performance
Incorrect ignition timing
Faulty spark plug(s)
Faulty ignition coil assembly(s)
Faulty CMP sensor
Faulty ECM (or PCM)
Adjust
Adjust, clean or replace
Replace
Replace
Replace
DIAGNOSTIC FLOW TABLE
STEP ACTION YES NO
1 Was “Engine Diagnostic Flow Table” in SECTION 6
or 6-1 performed? Go to Step 2. Go to “Engine Diag-
nostic Flow Table” in
SECTION 6 or 6-1.
2
Ignition Spark Test
1) Check all spark plug for condition and type, refer-
ring to “Spark Plug” in this section.
2) If OK, perform ignition spark test, referring to
“Ignition Spark Check” in this section.
Is spark emitted from all spark plugs?
Go to Step 8 on the
next page. Go to Step 3.
3 Diagnostic Trouble Code (DTC) Check
1) Check DTC stored in ECM (or PCM), referring to
“Diagnostic Trouble Code (DTC) Check” in
SECTION 6E1 or 6E2.
Is DTC stored?
Go to applicable flow
table corresponding
to that code No. in
SECTION 6E1 or
6E2. Go to Step 4.
4 Electrical Connection Check
1) Check ignition coil assemblies for electrical con-
nection.
Are they connected securely?
Go to Step 5. Connect securely.
5 Ignition Coil Assembly Power Supply, Ground and
Trigger Signal Circuits Check
1) Check these circuits for open and short.
Are circuits in good condition? Go to Step 6 on the
next page. Repair or replace.