2001 SUZUKI GRAND VITARA Owners Manual

6F2-2 IGNITION SYSTEM (FOR H27 ENGINE)
General Description
The ignition system is a direct ignition system. It consists of the parts as described below and has an electronic
ignition control system.
•ECM (or PCM)
It detects the engine condition through the signals from the sensors, determines the most suitable ignition
timing and time for electricity to flow to the primary coil and sends a signal to the igniter (in ignition coil
assembly).
•Ignition coil assembly (including an igniter and an ignition coil)
The ignition coil assembly has a built-in igniter and ignition coil which turns ON and OFF the primary current
of the ignition coil according to the signal from ECM (or PCM). When the ignition coil primary current is
turned OFF, a high voltage is induced in the secondary wiring. One ignition coil is in charge of ignition of one
cylinder only.
•Spark plug and noise suppressor
•CMP sensor, TP sensor, ECT sensor, IAT sensor, VSS, knock sensor and MAF sensor
For their details, refer to Section 6E2.
This ignition system does not have a distributor and high-tension cords but each cylinder has an ignition coil
assembly (igniter and ignition coil) and the secondary voltage which occurred in the ignition coil is sent to the
spark plug directly. Also, the signal(s) are sent from the CMP sensor to ECM (or PCM) so as to control each igni-
tion coil independently through the igniter (in ignition coil assembly).
Components
NOTE:
For other components not found in this figure, refer to Section 6E2.
1. Ignition coil assembly (igniter and ignition coil)
2. CMP sensor
3. Noise suppressor
4. ECM (or PCM)
5. Spark plug

IGNITION SYSTEM (FOR H27 ENGINE) 6F2-3
System Wiring
NOTE:
For ECM (PCM) terminal assignment, refer to Section 6E2.
1. To ignition switch 8. Ignition coil assembly (For No.3 cylinder)
2.“IG COIL METER” fuse 9. Ignition coil assembly (For No.4 cylinder)
3. ECM (or PCM) 10. Spark plug
4. CMP sensor 11. Ignition coil assembly (For No.5 cylinder)
5. Noise suppressor 12. Ignition coil assembly (For No.6 cylinder)
6. Ignition coil assembly (For No.1 cylinder) 13. To main relay
7. Ignition coil assembly (For No.2 cylinder) 14. Sensed information

6F2-4 IGNITION SYSTEM (FOR H27 ENGINE)
Diagnosis
Diagnostic Flow Table
Condition Possible Cause Correction
Engine cranks, but will
not start or hard to
start (No spark)Blown fuse for ignition coil assembly Replace.
Loose connection or disconnection of lead wire Connect securely.
Faulty spark plug (s) Replace.
Faulty ignition coil assembly (s) Replace.
Faulty CMP sensor Replace.
Faulty ECM (or PCM) Replace.
Maladjusted ignition timing Adjust.
Poor fuel economy or
engine performanceIncorrect ignition timing Adjust.
Faulty spark plug(s) Replace.
Faulty ignition coil assembly (s) Replace.
Faulty CMP sensor Replace.
Faulty ECM (or PCM) Replace.
Faulty knock sensor Replace.
Step Action Yes No
1Was “ENGINE DIAGNOSTIC FLOW TABLE” in
Section 6-1 performed?Go to Step 2. Go to “ENGINE DIAG-
NOSTIC FLOW TABLE” in
Section 6-1.
2 Ignition Spark Test
1) Check all spark plug for condition and type,
referring to “SPARK PLUG” in this section.
2) If OK, perform ignition spark test, referring
to “IGNITION SPARK CHECK” in this sec-
tion.
Is spark emitted from all spark plugs?Go to Step 8. Go to Step 3.
3 Diagnostic Trouble Code (DTC) Check
1) Check DTC stored in ECM (or PCM), refer-
ring to “DIAGNOSTIC TROUBLE CODE
(DTC) CHECK” in Section 6E2.
Is DTC stored?Go to applicable flow table
corresponding to that
code No. in Section 6E2.Go to Step 4.
4 Electrical Connection Check
1) Check ignition coil assemblies for electrical
connection.
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. Repair or replace.
6 Ignition Coil Assembly Check
1) Substitute a known-good ignition coil
assembly and then repeat Step 2.
Is check result of Step 2 satisfactory?Malfunction of ignition coil
assembly.Go to Step 7.

IGNITION SYSTEM (FOR H27 ENGINE) 6F2-5
REFERENCE
Oscilloscope waveforms of CMP sensor REF signal and No.1
ignition trigger signal are as shown in figure when connecting
oscilloscope between terminal C51-1-13 of ECM (PCM) connec-
tor connected to ECM (PCM) and ground, and between terminal
C51-2-28 and ground. 7 CMP Sensor Check
1) Check CMP sensor.
Refer to Step 6 or 7 of “DTC P0340 DIAG.
FLOW TABLE” in Section 6-1.
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 TIM-
ING 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
1. REF signal of CMP sensor
2. No.1 ignition trigger signal
3. Primary coil current flow time

6F2-6 IGNITION SYSTEM (FOR H27 ENGINE)
Ignition Spark Check
1) Remove surge tank cover.
2) Disconnect injector coupler (1).
3) Remove spark plug and check it for condition and type, refer-
ring to “SPARK PLUG” in this section.
4) If OK, connect ignition coil coupler to ignition coil assembly
and connect spark plug to ignition coil assembly. Ground
spark plug.
5) Crank engine and check if each spark plug sparks.
If no spark is emitted, inspect the related parts as described
under “DIAGNOSIS” in this section.
6) After checking, install spark plug, referring to “SPARK PLUG”
in this section.
7) Connect injector coupler (1).
8) Install surge tank cover.
Ignition Timing Check and Adjustment
1) Start engine and warm it up to normal operating tempera-
ture.
2) Make sure that all of electrical loads except ignition are
switched off.
3) Check to be sure that idle speed is within specification.
Refer to Section 6E2.
4) Connect SUZUKI scan tool to DLC (1) with ignition switch
OFF, restart engine and fix ignition timing by using fixed
spark mode of SUZUKI scan tool.
Special tool
(A) : SUZUKI scan tool WARNING:
Without disconnection of injector coupler, combustible
gas may come out from spark plug holes during this test
and may get ignited in engine room.
NOTE:
Before starting engine, place transmission gear shift
lever in “Neutral” (shift selector lever to “P” range for A/T
model), and set parking brake.

IGNITION SYSTEM (FOR H27 ENGINE) 6F2-7
5) Set timing light to ignition harness for No.1 cylinder.
6) Using timing light, check that timing observed from viewpoint
is within specification.
Initial ignition timing of viewpoint
(when it is fixed by SUZUKI scan tool) :
5 ± 1° BTDC
Ignition order :
1-6-5-4-3-2
Special tool
(A) : 09930-76420
7) If ignition timing is out of specification, loosen flange bolt,
adjust timing by turning CMP sensor (1) while engine is run-
ning, and then tighten bolt (2).
Tightening torque
CMP sensor bolt (a) : 15 N·m (1.5 kg-m, 11.0 lb-ft)
8) After tightening bolt (2), recheck that ignition timing is within
specification.
9) After checking and/or adjusting, end fixed spark mode of
SUZUKI scan tool.
10) With engine idling (closed throttle position and vehicle
stopped), check that ignition timing is about BTDC 12-16°
(shown in the figure). Also, check that increasing engine
speed advances ignition timing.
If above check results are not satisfactory, check input sig-
nals related to this system.
1. Timing mark on crankshaft pulley
NOTE:
In this state, ignition timing may vary more or less of ini-
tial ignition timing but it is nothing abnormal.
1. Timing mark on crankshaft pulley

6F2-8 IGNITION SYSTEM (FOR H27 ENGINE)
On-Vehicle Service
Ignition Coil Assembly (Igniter and Ignition
Coil)
REMOVAL
1) Remove ignition coil cover.
2) Disconnect ignition coil coupler.
3) Remove ignition coil bolt (1), and then pull out ignition coil
assembly (2).
INSPECTION
Check ignition coil assembly for the following :
•Damage
•Deterioration
•Terminal for corrosion
INSTALLATION
Install in reverse order of removal.
Spark Plug
REMOVAL
1) Remove ignition coil cover.
2) Disconnect ignition coil coupler.
3) Remove ignition coil bolt (1), and then pull out ignition coil
assembly (2).
4) Remove spark plug (3).

IGNITION SYSTEM (FOR H27 ENGINE) 6F2-9
INSPECTION
Inspect them for electrode wear, carbon deposits and Insulator
damage.
If any abnormality is found, replace them with specified new plug.
Spark plug air gap “a” :
1.0 – 1.1 mm (0.039 – 0.043 in.)
Spark plug type :
DENSO K20PR-U11/SK16PR11
NGK BKR6E-11/*IFR5J11
INSTALLATION
1) Install spark plug (3) and tighten them to specified torque.
Tightening torque
Spark plug (a) : 25 N·m (2.5 kg-m, 18.0 lb-ft)
2) Install ignition coil assembly (2) securely.
3) Tighten ignition coil bolt (1), and then connect ignition coil
coupler.
4) Install ignition coil cover.CAUTION:
When servicing the iridium/platinum spark plugs (slender
center electrode type plugs), do not touch the center
electrode to avoid damage to it. The electrode is not
strong enough against mechanical force as it is slender
and its material is not mechanically tough.
NOTE:
Under –25°C (–13°F), it is highly recommended to use the
spark plugs with an asterisk (*) for better engine starting
performance.