AC200625
Cylinder block
drain plug
AC
ON-VEHICLE SER VICE
ENGINE COOLING14-22
5.App l y the designa ted sealant to t he scre w area of
th e cylin der block drain plu g , and then tighten to
th e st and ard torq ue.
Sp e c ified s ealant: 3 M Nut Loc king Part
No. 4171 o r e quivale n t
Ti ghtenin g torque:
40 ± 5 N⋅m <4G1>
44 ± 5 N⋅m <4G6>
6.Securely tighten t he drain plug of t he radiator .
7.Reinst all the ra diato r con denser t ank.
CAUTION
Do not use alcohol or methanol anti-freeze or any
engine coolants mixed with alcohol or methanol
anti-freeze. The use of an improper anti-freeze
can cause corrosion of the aluminium compo
-
nents.
AC303612AB
MB991871
AIR HOSE
8. By referring to the section on coolant, select an
appropriate concentration for safe operating
temperature within the range of 30 to 60%. Use
special tool LLC changer (MB991871) to refill the
coolant. A convenient mixture is a 50% water and
50% antifreeze solution (freezing point:
−31°C).
Recommended antifreeze: DIAQUEEN SUPER LONG LIFE COOLANT or equivalent
Quantity:
5.0 L <4G1>
7.0 L <4G6>
NOTE: For how to use special tool MB991871,
refer to its manufacturer’s instructions.
9. Reinstall the radiator cap.
10.Start the engine and let it warm up until the thermostat opens.
11.After repeatedly revving the engine up to 3,000 r/min several times, then stop the engine.
12.Remove the radiator cap after the engine has become cold, and pour in coolant up to the brim.
Reinstall the cap.
CAUTION
Do not overfill the radiator condenser tank.
13.Add coolant to the radiator condenser tank between the "F" and "L" mark if necessary.
CONCENTRATION MEASUREMENT
M1141001100352
Measure the temperature and specific gravity of the
engine coolant to check the antifreeze concentration.
Standard value: 30 − 60% (allowable concentra-
tion range)
Recommended antifreeze: DIAQUEEN SUPER
LONG LIFE COOLANT or equivalent
CAUTION
If the concentration of the anti-freeze is below
30%, the anti-corrosion property will be
adversely affected. In addition, if the concentra
-
tion is above 60%, both the anti-freezing and
engine cooling properties will decrease, affecting
the engine adversely. For these reasons, be sure
to maintain the concentration level within the
specified range.
COOLING FAN MOTOR DRIVE CONTROL
UNIT CHECK
M1141006100250
1. Remove the cooling fan motor drive control unit connector.
AC103195
Y1716AU
1
23
AC
Cooling fan motor
drive control unit
2. Turn the ignition switch to the "ON" position, and
measure the voltage between terminal 1 and 3 at
the harness side connector.
Standard value: system voltage
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 ASSEMB LY . . . . .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
AKX00183
VoltageTime
Approximately
14.4 V
AC
Rota tion of the excited fi eld coil gene rates AC volt-
age in the sta t or .
This alternatin g cur r ent is rectified throu gh diodes to
DC volt
age h a ving a waveform sh own in t he illustra
-
tion.
The average outpu t volt a ge flu c tua t es slightly with
the alternato
r load con d ition.
When the ign i tion switch is t u rned on, current flows in
the field coil and initial e
x cit a tion of the field coil
occurs.
When the st ator coil beg ins to gen erate p o wer af ter
the eng
ine is st a r ted, th e fie l d coil is excited by th e
output
curren t of th e st ator coil.
The alternator outpu t volt a ge rises as th e fie l d cur-
rent increa ses and it falls a s the field cu rrent
decre
ases. Whe n the b a ttery volt a ge (alternato r "S"
terminal volt
ag e) reaches a regulated volt ag e of
approximately 14.4
V , the field current is cut o f f.
When th
e batte ry volt age drop s be low the regulated
volt
ag e, the volt ag e regulator re gulat es th e outp u t
volt
ag e to a const ant level by contro lling the field cur
-
rent.
In addition, when th e fie l d current is const a n t, the
altern
ator ou tput volt age rise s as the e ngine spe ed
increase
s .
SYSTEM DIAGRAM
AK400308
Alternator
B
Stator coil
Engine-ECU
Engine-A/T-ECU
G
SL
FR
<4G1>
Voltage regulator Charge warning lightIgnition switch
Battery
Field coil
+
–
AB
AL TERNA T O R SPECIFICA T IONS
Item4G14G6
Ty p eBattery voltage sensing
Rated output V/A12/8012/110
Voltage regulatorElectronic built-in type
CHARGING SYSTEM
ENGINE ELECTRICAL16-4
2. Turn the ignition switch to the "LOCK" (OFF)
position.
3. Disconnect the negative battery cable.
4. Connect a clamp-type DC test ammeter with a
range of 0
− 120 A to the alternator "B" terminal
output wire.
NOTE: The way of disconnecting the alternator
output wire and of connecting the ammeter is pos
-
sibly not found the problem that the output current
is dropping due to the insufficient connection
between terminal "B" and the output wire.
5. Connect a digital-type voltmeter between the
alternator "B" terminal and the battery (+)
terminal. [Connect the (+) lead of the voltmeter to
the "B" terminal and the connect the (-) lead of the
voltmeter to the battery (+) cable].
6. Reconnect the negative battery cable.
7. Connect a tachometer or the M.U.T.-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. Start the engine.
10.With the engine running at 2,500 r/min, turn the
headlamps and other lamps on and off to adjust
the alternator load so that the value displayed on
the ammeter is slightly above 30 A.
Adjust the engine speed by gradually decreasing
it until the value displayed on the ammeter is 30
A. Take a reading of the value displayed on the
voltmeter at this time.
Limit: maximum 0.3 V
NOTE: When the alternator output is high and the
value displayed on the ammeter does not
decrease until 30 A, set the value to 40 A. Read
the value displayed on the voltmeter at this time.
When the value range is 40 A, the limit is maxi
-
mum 0.4 V.
11.If the value displayed on the voltmeter is above
the limit value, there is probably a malfunction in
the alternator output wire, so check the wiring
between the alternator "B" terminal and the
battery (+) terminal (including fusible link).
If a terminal is not sufficiently tight or if the
harness has become discolored due to
overheating, repair and then test again.
12.After the test, run the engine at idle.
13.Turn off all lamps and the ignition switch.
14.Remove the tachometer or the M.U.T.-II/III.
15.Disconnect the negative battery cable.
16.Disconnect the ammeter and voltmeter.
17.Connect the negative battery cable.
CHARGING SYSTEM
ENGINE ELECTRICAL16-6
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 (+) ter
-
minal.
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 output
NOTE: .
•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 dis
-
charge the battery or by using the lighting sys-
tem 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 M.U.T.-II/III.
16.Disconnect the negative battery cable.
17.Disconnect the ammeter and voltmeter.
18.Connect the negative battery cable.
CHARGING SYSTEM
ENGINE ELECTRICAL16-8
If the voltage is not within the standard value,
there is a malfunction of the voltage regulator or of
the alternator.
14.After the test, lower the engine speed to the idle speed.
15.Turn the ignition switch to the "LOCK" (OFF) position.
16.Remove the tachometer or the M.U.T.-II/III.
17.Disconnect the negative battery cable.
18.Disconnect the ammeter and voltmeter.
19.Connect the alternator output wire to the alternator "B" terminal.
20.Remove the special tool, and return the connector
to the original condition.
21.Connect the negative battery cable.
Voltage Regulation Table
Standard value:
Inspection terminalVoltage regulator ambient
temperature
°C
Voltage V
Terminal "S"−2014.2 − 15.4
2013.9 − 14.9
6013.4 − 14.6
8013.1 − 14.5