IGNITION SYSTEM 6F-3
DIAGNOSIS
ConditionPossible CauseCorrection
Engine cranks, but will
not start or hard to startBlown fuse for ignition coil
Loose connection or disconnection of lead wire or
high-tension cord(s)
Faulty high-tension cord(s)
Faulty spark plug(s)
Cracked rotor or cap
Maladjusted signal rotor air gap
Faulty ignition coil
Faulty noise suppressor
Faulty CMP sensor
Faulty igniter
Faulty ECM (or PCM)
Maladjusted ignition timingReplace
Connect securely
Replace
Adjust, clean or replace
Replace
Adjust
Replace
Replace
Replace
Replace
Replace
Adjust
Poor fuel economy or
engine performanceIncorrect ignition timing
Faulty spark plug(s) or high-tension cord(s)
Faulty ECM (or PCM)Adjust
Adjust, clean or replace
Replace
DIAGNOSTIC FLOW TABLE
STEPACTIONYESNO
1Was “Engine Diagnostic Flow Table” in SECTION 6
performed?Go to Step 2.Go to “Engine
Diagnostic Flow
Table” in SECTION 6.
2Ignition Spark Test
1) Check all spark plug for condition and type,
referring to “Spark Plugs” 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 11 on the
next page.Go to Step 3.
3Diagnostic Trouble Code (DTC) Check
1) Check DTC stored in ECM (or PCM), referring to
“Diagnostic Trouble Code (DTC) Check” in
SECTION 6.
Is DTC stored?Go to applicable flow
table corresponding to
that code No. in
SECTION 6.Go to Step 4.
4Electrical Connection and Noise Suppressor Check
1) Check ignition coil for electrical connection and
noise suppressor for conductivity.
Are they good condition?Go to Step 5.Repair or replace.
5High-tension Cord Check
1) Check high-tension cord for resistance, referring
to “High-tension Cords” in this section.
Is check result satisfactory?Go to Step 6.Replace high-tension
cord(s).
6F-4 IGNITION SYSTEM
STEPACTIONYESNO
6Ignition Coil Power Supply and Ground Circuit
Check
1) Check ignition coil power supply (“B/W” wire)
circuit for open and short.
Are circuits in good condition?Go to Step 7.Repair or replace.
7Ignition Coil Check
1) Check ignition coil for resistance, referring to
“Ignition Coil” in this section.
Is check result satisfactory?Go to Step 8.Replace ignition coil
assembly.
8CMP Sensor Check
1) Check CMP sensor and signal rotor, referring to
“Distributor Unit” in this section.
Is check result satisfactory?Go to Step 9 on the
next page.Adjust or replace.
9Ignition Trigger Signal Circuit Check
1) Check ignition trigger signal (“Br / Y” or “Or” wire)
circuit for open, short and poor connection.
Are circuits in good condition?Go to Step 10.Repair or replace.
10Igniter Check
1) Check igniter, referring to “Igniter” in this section.
Is check result satisfactory?Go to Step 11.Replace igniter.
11Ignition Timing Check
1) Check initial ignition timing and ignition timing
advance, referring to “Ignition Timing” in this
section.
Is check result satisfactory?Substitute a known-
good ECM (or PCM)
and then repeat
Step 2.Go to Step 12.
12Ignition Timing Adjustment and Recheck
1) Adjust initial ignition timing, referring to “Ignition
Timing” in this section.
2) Recheck initial ignition timing and ignition timing
advance, referring to “Ignition Timing” in this
section.
Is check result satisfactory?System is in good
condition.Substitute a known-
good ECM (or PCM)
and then repeat
Step 2.
1. Pickup coil
2. Signal rotor
3. Screws
1. Distributor
2. Coupler
3. Ohmmeter
6F-8 IGNITION SYSTEM
DISTRIBUTOR
DISTRIBUTOR CAP AND ROTOR
INSPECTION
Check cap and rotor for crack and their terminals for corrosion and
wear. Replace as necessary.
SIGNAL ROTOR AIR GAP
INSPECTION
1) Remove distributor cap and rotor.
2) Using thickness gauge, measure air gap, between signal rotor
tooth and CMP sensor (generator).
Signal rotor air gap “a”: About 0.2 mm (about 0.008 in.)
3) If gap is out of specification, loose CMP sensor (signal genera-
tor) securing screws. Using blade (–) screw driver, move CMP
sensor (generator) and adjust gap to specification. After adjust-
ment, tighten securing screws and recheck gap.
NOTE:
Check to make sure that CMP sensor (signal generator)
tooth is free from any metal particles.
4) Install distributor cap and rotor.
CMP SENSOR (PICKUP COIL) RESISTANCE
INSPECTION
1) Disconnect distributor lead coupler.
2) Measure resistance of pickup coil by using ohmmeter.
3) If resistance is out of specification, replace CMP sensor (signal
generator) as follows.
Pickup coil resistance:
185 – 275 Ω at – 10C (14F) – 50C (122F)
240 – 325 Ω at 50C (122F) – 100C (212F)
4) Remove distributor cap and rotor.
5) Remove CMP sensor (signal generator) securing screws and
lead wire clamp screws.
6) Replace CMP sensor (signal generator).
7) Adjust signal rotor air gap to specifications as previously out-
lined.
8) Install rotor, distributor cap seal and cap.
1. Cap
2. Cap seal
3. Cap screw
4. Rotor
5. CMP sensor
(Signal generator)
6. Screw
7. Cover
8. Housing
9. O-ring
A: Slot offset
1. Distributor case
2. O-ring3. Distributor coupling
4. Camshaft
6F-10 IGNITION SYSTEM
DISTRIBUTOR UNIT
DISMOUNTING
1) Disconnect distributor lead coupler.
2) Remove distributor cap screws and cap.
3) Remove distributor flange bolts.
4) Pull out distributor housing assembly.
REMOUNTING
NOTE:
Before installing distributor, check to make sure that its
O-ring is in good condition.
If new O-ring is installed, apply oil.
1) Install distributor without cap to camshaft.
Fit the dogs of distributor coupling into the slots of camshaft,
when installing. The dogs of distributor coupling are offset.
Therefore, if the dogs can not shaft by 180 degree and try again.
2) Lightly install flange bolts and prepare for ignition timing adjust-
ment.
3) Check to make sure that rotor is in good condition.
4) Inspect distributor cap and clean or replace as required.
5) Make sure that distributor cap seal is placed properly and install
cap, and then fasten it with screws.
6) Connect distributor lead coupler.
7) Check and adjust ignition timing as previously outlined.
1. ECM (PCM)
2. Ignition coil assembly
for No.1 and No.4 spark plugs
3. Ignition coil assembly
for No.2 and No.3 spark plugs4. CMP sensor
5. CKP sensor
6. MAP sensor
7. ECT sensor
8. IAT sensor9. TP sensor
10. VSS (A / T)
11. Transmission range switch (A / T)
12. High-tension cords
13. VSS (speedometer) (M / T)
14. Data link connector
6F1-2 IGNITION SYSTEM (SFI FOR G13)
GENERAL DESCRIPTION
The ignition system is an electronic (distributorless) ignition system. It consists of the parts as described below and
has an electronic ignition control system.
ECM (PCM)
It detects the engine and vehicle conditions 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 ignitor (power unit) in
the ignition coil assembly.
Ignition coil assembly (including an ignitor)
The ignition coil assembly has a built-in ignitor which turns ON and OFF the current flow to the primary coil accord-
ing to the signal from ECM (PCM). When the current flow to the primary coil is turned OFF, a high voltage is in-
duced in the secondary coil.
High tension cords and spark plugs.
CMP sensor (Camshaft position sensor) and CKP sensor (Crankshaft position sensor)
Using signals from these sensors, ECM (PCM) identifies the specific cylinder whose piston is in the compression
stroke and detects the crank angle.
TP sensor, ECT sensor, MAP sensor and other sensors / switches
Refer to section 6E2 for details.
Although this ignition system does not have a distributor, it has two ignition coil assemblies (one is for No.1 and
No.4 spark plugs and the other is for No.2 and No.3 spark plugs). When an ignition signal is sent from ECM (PCM)
to the ignitor in the ignition coil assembly for No.1 and No.4 spark plugs, a high voltage is induced in the secondary
coil and that passes through the high-tension cords and causes No.1 and No.4 spark plugs to spark simultaneously.
Likewise, when an ignition signal is sent to the ignitor in the other ignition coil assembly, No.2 and No.3 spark plugs
spark simultaneously.
SYSTEM COMPONENTS
1. Ignition switch
2. Main relay
3. Ignition coil assembly
for No.1 and No.4
spark plugs
4. Ignition coil assembly
for No.2 and No.3
spark plugs5. CMP sensor
6. CKP sensor
7. No.1 spark plug
8. No.2 spark plug
9. No.3 spark plug
10. No.4 spark plug11. Sensed information
MAP sensor
ECT sensor
IAT sensor
TP sensor
VSSPark / Neutral position signal
(A / T)
Electric load signal
Engine start signal
IGNITION SYSTEM (SFI FOR G13) 6F1-3
SYSTEM WIRING DIAGRAM
DIAGNOSIS
ConditionPossible CauseCorrection
Engine cranks, but will
not start or hard to
startNo spark
Blown fuse for ignition coil
Loose connection or disconnection of lead
wire or high-tension cord(s)
Faulty high-tension cord(s)
Faulty spark plug(s)
Faulty ignition coil
Faulty CKP sensor or crankshaft timing belt
pulley
Faulty ECM (PCM)
Replace.
Connect securely.
Replace.
Adjust, clean or replace.
Replace ignition coil assembly.
Clean, tighten or replace.
Replace.
Poor fuel economy or
engine performanceIncorrect ignition timing
Faulty spark plug(s) or high-tension cord(s)
Faulty ignition coil assembly
Faulty CKP sensor or crankshaft timing belt
pulley
Faulty ECM (PCM)Check related sensors and
crankshaft timing belt pulley.
Adjust, clean or replace.
Replace.
Clean, tighten or replace.
Replace.
[G10 Engine Model]
1. PCM
2. Camshaft position (CMP) sensor
3. Throttle position (TP) sensor
4. Engine coolant temperature (ECT) sensor
5. Transmission range sensor (shift switch)
6. Output shaft speed sensor (A / T VSS)7. Malfunction indicator lamp (MIL)
8. Data link connector (DLC)
9. Shift solenoid-A
(No.1, Direct clutch solenoid valve)
10. Shift solenoid-B
(No.2, 2nd brake solenoid valve)11. Ignition switch
12. Main relay
13. Inhibitor switch
14. To starter
15. Terminal arrangement of PCM coupler
(Viewed from harness side)
AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC) 7B-5
ELECTRONIC SHIFT CONTROL SYSTEM
7B-6 AUTOMATIC TRANSMISSION (3 A / T) (VEHICLE WITH WU-TWC)
[G13 Engine Model]
1. PCM
2. Camshaft position (CMP) sensor
3. Throttle position (TP) sensor
4. Engine coolant temperature (ECT) sensor
5. Transmission range sensor (shift switch)
6. Output shaft speed sensor (A / T VSS)7. Malfunction indicator lamp (MIL)
8. Data link connector (DLC)
9. Shift solenoid-A
(No.1, Direct clutch solenoid valve)
10. Shift solenoid-B
(No.2, 2nd brake solenoid valve)11. Ignition switch
12. Main relay
13. Inhibitor switch
14. To starter
15. Terminal arrangement of PCM coupler
(Viewed from harness side)