
16-1
GROUP 16
ENGINE
ELECTRICAL
CONTENTS
CHARGING SYSTEM . . . . . . . .
16-2
GENERAL INFORMATION . . . . . .
16-2
SERVICE SPECIFICATIONS. . . . .16-3
SPECIAL TOOL . . . . . . . . . . . . . . .16-3
ON-VEHICLE SERVICE. . . . . . . . .16-3
ALTERNATOR OUTPUT LINE VOLTAGE
DROP TEST . . . . . . . . . . . . . . . . . . . . . 16-3
OUTPUT CURRENT TEST . . . . . . . . . . 16-5
REGULATED VOLTAGE TEST . . . . . . . 16-7
WAVEFORM CHECK USING AN
OSCILLOSCOPE . . . . . . . . . . . . . . . . . . 16-9
ALTERNATOR ASSEMBLY . . . . .16-12
REMOVAL AND INSTALLATION
<4G1> . . . . . . . . . . . . . . . . . . . . . . . . . . 16-12
REMOVAL AND INSTALLATION
<4G6> . . . . . . . . . . . . . . . . . . . . . . . . . . 16-13
DISASSEMBLY AND REASSEMBLY . . 16-15
INSPECTION . . . . . . . . . . . . . . . . . . . . . 16-17
STARTING SYSTEM . . . . . . . . .16-19
GENERAL INFORMATION . . . . . .
16-19
SERVICE SPECIFICATIONS. . . . .16-20
STARTER MOTOR ASSEMBLY . .16-21
REMOVAL AND INSTALLATION
<4G1> . . . . . . . . . . . . . . . . . . . . . . . . . . 16-21
REMOVAL AND INSTALLATION
<4G6> . . . . . . . . . . . . . . . . . . . . . . . . . . 16-22
STARTER MOTOR ASSEMBLY
INSPECTION . . . . . . . . . . . . . . . . . . . . . 16-23
DISASSEMBLY AND REASSEMBLY . . 16-26
INSPECTION . . . . . . . . . . . . . . . . . . . . . 16-27
IGNITION SYSTEM . . . . . . . . . 16-30
GENERAL INFORMATION . . . . . .
16-30
SERVICE SPECIFICATIONS . . . . .16-31
SPECIAL TOOL . . . . . . . . . . . . . . .16-31
ON-VEHICLE SERVICE . . . . . . . . .16-32
IGNITION COIL (WITH BUILT-IN
POWER TRANSISTOR) CHECK . . . . . . 16-32
RESISTIVE CORD CHECK . . . . . . . . . . 16-32
SPARK PLUG CHECK AND
CLEANING <4G1> . . . . . . . . . . . . . . . . . 16-32
SPARK PLUG CHECK AND
CLEANING <4G6> . . . . . . . . . . . . . . . . . 16-33
CAMSHAFT POSITION SENSOR
CHECK . . . . . . . . . . . . . . . . . . . . . . . . . . 16-33
CRANK ANGLE SENSOR CHECK . . . . 16-33
DETONATION SENSOR CHECK . . . . . 16-33
IGNITION SECONDARY VOLTAGE
WAVEFORM CHECK USING AN
OSCILLOSCOPE . . . . . . . . . . . . . . . . . . 16-33
IGNITION COIL RELAY CHECK . . . . . . 16-37
IGNITION COIL . . . . . . . . . . . . . . . .16-38
REMOVAL AND INSTALLATION
<4G1>. . . . . . . . . . . . . . . . . . . . . . . . . . . 16-38
REMOVAL AND INSTALLATION
<4G6>. . . . . . . . . . . . . . . . . . . . . . . . . . . 16-39
CAMSHAFT POSITION SENSOR .16-40
REMOVAL AND INSTALLATION . . . . . . 16-40
CRANKSHAFT POSITION SENSOR16-41
REMOVAL AND INSTALLATION
<4G1>. . . . . . . . . . . . . . . . . . . . . . . . . . . 16-41
REMOVAL AND INSTALLATION
<4G6>. . . . . . . . . . . . . . . . . . . . . . . . . . . 16-42
DETONATION SENSOR . . . . . . . .16-43
REMOVAL AND INSTALLATION . . . . . . 16-43

CHARGING SYSTEM
ENGINE ELECTRICAL16-2
CHARGING SYSTEM
GENERAL INFORMATIONM1161000100522
The charging system uses the alternator output to
keep the battery charged at a constant level under
various electrical loads.
OPERATION
Rotation of the excited field coil generates AC
voltage in the stator.
This alternating current is rectified through diodes to
DC voltage having a waveform shown in the
illustration.The average output voltage fluctuates slightly with
the alternator load condition.
When the ignition switch is turned on, current flows in
the field coil and initial excitation of the field coil
occurs.
When the stator coil begins to generate power after
the engine is started, the field coil is excited by the
output current of the stator coil.
The alternator output voltage rises as the field
current increases and it falls as the field current
decreases. When the battery voltage (alternator "S"
terminal voltage) reaches a regulated voltage of
approximately 14.4 V, the field current is cut off.
When the battery voltage drops below the regulated
voltage, the voltage regulator regulates the output
voltage to a constant level by controlling the field
current.
In addition, when the field current is constant, the
alternator output voltage rises as the engine speed
increases.
SYSTEM DIAGRAM
ALTERNATOR SPECIFICATIONS
AKX00183
Voltage
Time
Approximately
14.4 V
AC
AK400308
Alternator
B
Stator coil
Engine-ECU
Engine-A/T-ECU
G
S
L
FR <4G1>
Voltage regulatorCharge warning lightIgnition switch
Battery Field coil
+
–
AB
Item 4G1 4G6
Type Battery voltage sensing
Rated output V/A 12/80 12/110
Voltage regulator Electronic built-in type

CHARGING SYSTEM
ENGINE ELECTRICAL16-3
SERVICE SPECIFICATIONSM1161000300258
SPECIAL TOOLM1161000600163
ON-VEHICLE SERVICE
ALTERNATOR OUTPUT LINE VOLTAGE DROP TESTM1161000900346
This test determines whether the wiring from the
alternator "B" terminal to the battery (+) terminal
(including the fusible line) is in a good condition or
not.
1. Always be sure to check the following before the
test.
•Alternator installation•Drive belt tension
(Refer to GROUP 11A − On-vehicle Service
<4G1> P.11A-7 or GROUP 11C − On-vehicle
Service <4G6> P.11C-7.)
•Fusible link
•Abnormal noise from the alternator while the
engine is running Item Standard value Limit
Alternator output line voltage drop (at 30 A) V
−maximum 0.3
Regulated voltage ambient
temperature at voltage regulator V−20°C14.2 − 15.4
−
20°C 13.9 − 14.9
−
60°C 13.4 − 14.6
−
80°C 13.1 − 14.5
−
Output current
−70 % of normal output current
Tool Number Name Use
MB991519 Alternator test harness Checking the alternator
("S" terminal voltage)
AK203361AD
AlternatorAmmeter (clamp-type)
Voltmeter (digital-type)
"B" terminalBattery

CHARGING SYSTEM
ENGINE ELECTRICAL16-6
7. Connect a tachometer or the MUT-II/III (Refer to
GROUP 11A − On-vehicle Service − Idle speed
check <4G1> P.11A-11 or GROUP 11C −
On-vehicle Service − Idle speed check <4G6>
P.11C-11).
8. Leave the hood open.
9. Check that the reading on the voltmeter is equal
to the battery voltage.
NOTE: If the voltage is 0 V, the cause is probably
an open circuit in the wire or fusible link between
the alternator "B" terminal and the battery (+)
terminal.
10.Turn the light switch on to turn on headlamps and
then start the engine.
11.Immediately after setting the headlamps to high
beam and turning the heater blower switch to the
high revolution position, increase the engine
speed to 2,500 r/min and read the maximum
current output value displayed on the ammeter.
Limit: 70 % of normal current outputNOTE: .
•For the nominal current output, refer to the
Alternator Specifications.
•Because the current from the battery will soon
drop after the engine is started, the above step
should be carried out as quickly as possible in
order to obtain the maximum current output
value.
•The current output value will depend on the
electrical load and the temperature of the
alternator body.
•If the electrical load is small while testing, the
specified level of current may not be output
even though the alternator is normal. In such
cases, increase the electrical load by leaving
the headlamps turned on for some time to
discharge the battery or by using the lighting
system in another vehicle, and then test again.
•The specified level of current also may not be
output if the temperature of the alternator body
or the ambient temperature is too high. In such
cases, cool the alternator and then test again.
12.The reading on the ammeter should be above the
limit value. If the reading is below the limit value
and the alternator output wire is normal, remove
the alternator from the engine and check the
alternator.
13.Run the engine at idle after the test.
14.Turn the ignition switch to the "LOCK" (OFF)
position.
15.Remove the tachometer or the MUT-II/III.
16.Disconnect the negative battery cable.
17.Disconnect the ammeter and voltmeter.
18.Connect the negative battery cable.

STARTING SYSTEM
ENGINE ELECTRICAL16-20
STARTER MOTOR SPECIFICATIONS
SERVICE SPECIFICATIONS
M1162000300068
Item 4G1 4G6
Type Reduction drive with planetary
gearReduction drive with planetary gear
Rated output kW/V 1.2/12 1.4/12
Number of pinion teeth 8 8
Item Standard value Limit
Pinion gap mm 0.5 − 2.0
−
Commutator run-out mm
−0.05
Commutator diameter mm 29.4 28.8
Undercut depth mm 0.5 0.2

STARTING SYSTEM
ENGINE ELECTRICAL16-23
STARTER MOTOR ASSEMBLY INSPECTIONM1162001100205
PINION GAP ADJUSTMENT
1. Disconnect the field coil wire from the M-terminal
of the magnetic switch.
2. Connect a 12-volt battery between the S-terminal
and M-terminal.
CAUTION
This test must be performed quickly (in less than
10 seconds) to prevent the coil from burning.
3. Set the switch to "ON", and the pinion will move
out.
4. Check the pinion-to-stopper clearance (pinion
gap) with a feeler gauge.
Standard value: 0.5 − 2.0 mm5. If the pinion gap is out of specification, adjust by
adding or removing gasket(s) between the
magnetic switch and front bracket.
MAGNETIC SWITCH PULL-IN TEST
1. Disconnect the field coil wire from the M-terminal
of the magnetic switch.
CAUTION
This test must be performed quickly (in less than
10 seconds) to prevent the coil from burning.
2. Connect a 12-volt battery between the S-terminal
and M-terminal.
3. If the pinion moves out, the pull-in coil is good. If it
doesn't, replace the magnetic switch.
AK300648AB
<4G1>
Switch
S
M
Wire
Battery Starter
motor B
AKX01238
<4G6>
B MS
batterySwitch
Starter
motorWire
AG
AKX00198
Stopper
Pinion gap Pinion
AC
AKX00199
AK300649AB
<4G1>
S
M
Wire
Battery Starter
motor B
AKX01242
<4G6>
S
B M
Battery
Starter
motorWire
AF

STARTING SYSTEM
ENGINE ELECTRICAL16-24
MAGNETIC SWITCH HOLD-IN TEST
1. Disconnect the field coil wire from the M-terminal
of the magnetic switch.
CAUTION
This test must be performed quickly (in less than
10 seconds) to prevent the coil from burning.
2. Connect a 12-volt battery between the S-terminal
and body.
3. Manually pull out the pinion as far as the pinion
stopper position.
4. If the pinion remains out, everything is in order. If
the pinion moves in, the hold-in circuit is open.
Replace the magnetic switch.
FREE RUNNING TEST
1. Place the starter motor in a vise equipped with
soft jaws and connect a fully-charged 12-volt
battery to the starter motor as follows:
2. Connect a test ammeter (100-ampere scale) and
carbon pile rheostat in series between the battery
(+) terminal and starter motor terminal.
3. Connect a voltmeter (15-volt scale) across the
starter motor.
4. Rotate the rheostat to full-resistance position.
5. Connect the battery cable from the battery (-)
terminal to the starter motor body.
6. Adjust the rheostat until the battery voltage shown
on the voltmeter is 11 V.
7. Confirm that the maximum amperage is within the
specifications and that the starter motor turns
smoothly and freely.
Current:
<4G1> maximum 95 Amps
<4G6> maximum 90 Amps
AK300650AB
<4G1>
S
BMWire
Battery Starter
motor
AKX01244
<4G6>
S
B M
Battery
Starter
motorWire
AF
AK300651AB
<4G1>
S
A M
V BCarbon-pile rheostat
Battery
VoltmeterAmmeter
Starter
motor
AKX01246
<4G6>
S
M
BAmmeter
Carbon-pile
rheostat
Battery
Starter
motor
Voltmeter
AF
A
V

IGNITION SYSTEM
ENGINE ELECTRICAL16-31
IGNITION COIL SPECIFICATION
SPARK PLUG SPECIFICATIONS
SERVICE SPECIFICATIONS
M1163000300180
IGNITION COIL
SPARK PLUG
RESISTIVE CORD
SPECIAL TOOL
M1163000600288
Item Specification
Type Molded 2-coil
Items 4G1 4G66
NGK BKR6E-11 IGR6A11
DENSO K20PR-U11
−
CHAMPION RC8YC4
−
Item Standard value
Secondary coil resistance kΩ8.5 − 11 . 5
ItemsStandard value Limit
Spark plug gap mm 4G1 1.0 − 1.1
−
4G6 1.0 − 1.1 1.3
Item Standard value Limit
Resistance kΩ
−Maximum 19
Tool Number Name Use
MD998773 Detonation sensor
wrenchDetonation sensor
removal and installation