SPECIAL TOOLS
ENGINE COOLING14-4
MB991955
A: MB991824
B: MB991827
C: MB991910
D: MB991911
E: MB991825
F: MB991826MUT-III sub assembly
A: Vehicle
communication
interface (V.C.I.)
B: MUT-III USB cable
C: MUT-III main
harness A (Vehicles
with CAN
communication
system)
D: MUT-III main
harness B (Vehicles
without CAN
communication
system)
E: MUT-III
measurement
adapter
F: MUT-III trigger
harnessChecking the A/T
(Diagnosis display using the
MUT-III) Tool Number Name Use
MB991910
MB991826
MB991955
MB991911
MB991824
MB991827
MB991825
A
B
C
D
E
F
DO NOT USE
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
possibly 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 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. 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
maximum 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 MUT-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
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.
CHARGING SYSTEM
ENGINE ELECTRICAL16-7
REGULATED VOLTAGE TESTM1161001100354
This test determines whether the voltage regulator
correctly controlling the alternator output voltage.
1. Always be sure to check the following before the
test.
•Alternator installation
•Check that the battery installed in the vehicle is
fully charged.
(Refer to GROUP 54A − Battery − On-vehicle
Service − Charging P.54A-4).
•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
2. Turn the ignition switch to the "LOCK" (OFF)
position.
3. Disconnect the negative battery cable.
4. Use the special tool Alternator test harness
(MB991519) to connect a digital voltmeter
between the alternator "S" terminal and earth
[Connect the (+) lead of the voltmeter to the "S"
terminal, and then connect the (-) lead of the
voltmeter to a secure earth or to the battery (-)
terminal].
5. 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
possibly not found the problem that the output
current is dropping due to the insufficient
connection between terminal "B" and the output
wire.
6. Reconnect the negative battery cable.
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. Turn the ignition switch to the "ON" position and
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 "S" terminal and the battery (+)
terminal.
9. Turn all lamps and accessories off.
10.Start the engine.
11.Increase the engine speed to 2,500 r/min.
12.Read the value displayed on the voltmeter when
the alternator output current alternator becomes
10 A or less.
13.If the voltage reading conforms to the value in the
voltage regulation, then the voltage regulator is
operating normally.
AK300727AB
BatteryIgnition switch
Engine-ECU
Engine-A/T-ECU Ammeter (clamp-type)Load
Black MB991519
Voltmeter (digital-type) Red
YellowBlueAlternator B
FR
L
S
G
IGNITION SYSTEM
ENGINE ELECTRICAL16-33
SPARK PLUG CHECK AND CLEANING
<4G6>
M1163004300353
CAUTION
When pulling off the spark plug cable from the
plug always hold the cable cap, not the cable.
1. Remove the spark plug cables.
2. Remove the spark plugs.
CAUTION
•Do not attempt to adjust the gap of the iridium
plug.
•Always use a plug cleaner and finish cleaning
within 20 seconds. Do not use wire brushes.
Otherwise, the iridium and platinum tip may
be damaged.
3. Check the plug gap and replace if the limit is
exceeded.
Standard value: 1.0 − 1.1 mm
Limit: 1.3 mm
CAUTION
Be careful not to allow foreign matter in
cylinders.
4. Clean the engine plug holes.
5. Install the spark plugs.
CAMSHAFT POSITION SENSOR CHECKM1163004400219
Check the camshaft position sensor circuit if
self-diagnosis code No. P0340 is shown.
(Refer to GROUP 13A − Troubleshooting −
Inspection chart for diagnosis code <4G1> P.13A-15
or GROUP 13B − Troubleshooting − Inspection chart
for diagnosis code <4G6> P.13B-15 ).
CRANK ANGLE SENSOR CHECKM1163004500272
Check the crank angle sensor circuit if self-diagnosis
code No. P0335 is shown.
(Refer to GROUP 13A − Troubleshooting −
Inspection chart for diagnosis code <4G1> P.13A-15
or GROUP 13B − Troubleshooting − Inspection chart
for diagnosis code <4G6> P.13B-15 ).
DETONATION SENSOR CHECKM1163002900047
Check the detonation sensor circuit if self-diagnosis
code No. P0325 is shown.
(Refer to GROUP 13A − Troubleshooting −
Inspection chart for diagnosis code <4G1> P.13A-15
or GROUP 13B − Troubleshooting − Inspection chart
for diagnosis code <4G6> P.13B-15).
IGNITION SECONDARY VOLTAGE
WAVEFORM CHECK USING AN
OSCILLOSCOPE
M1163001700170
MEASUREMENT METHOD
1. Clamp the secondary pickup around the spark
plug cable.
NOTE: .
•The peak ignition voltage will be reversed
when the spark plug cables No. 2 and No. 4,
or No. 1 and No. 3 cylinders are clamped.
•Because of the two-cylinder simultaneous
ignition system, the waveforms for two
cylinders in each group appear during
waveform observation (No. 1 cylinder - No. 4
cylinder, No. 2 cylinder - No. 3 cylinder).
However, waveform observation is only
applicable for the cylinder with the spark plug
cable clamped by the secondary pickup.
•Identifying which cylinder waveform is
displayed can be difficult. For reference,
remember that the waveform of the cylinder
attached to the secondary pickup will be
displayed as stable.
2. Clamp the spark plug cable with the trigger
pickup.
NOTE: Clamp the trigger pickup to the same
spark plug cable clamped by the secondary
pickup.
AKX00383
AL
Platinum
tipIridium
tip
IGNITION SYSTEM
ENGINE ELECTRICAL16-34
STANDARD WAVEFORM
Observation Conditions
Observation Conditions (The only change from above condition is the pattern selector.)Function Secondary
Pattern height High (or Low)
Pattern selector Raster
Engine revolutions Curb idle speed
Pattern selector Display
AKX00278
kV
0 Secondary
ignition voltage
wave patternIgnition voltage
(point D)Spark line (point A)
Dwell sectionWave dampling reduction section (point B)
Point C
Time
AD
IGNITION SWITCH
CHASSIS ELECTRICAL54A-21
4. Select "Immobilizer," press "YES".
5. Select "Special Func", press "YES".
If diagnosis code No.11 exists, "Can't execute" will
be displayed. Check for diagnosis code
No.11(Refer to P.54A-9.)
6. Select "key ID register", press "YES".7. Input the password. Use the "UP" and "DOWN"
keys to change the current password digit to a
value between 0 and 9. Use the "LEFT" and
"RIGHT" keys to move to a different password
digit. Press the "YES" key to accept the password.
If an incorrect password is input five times in a
row, this screen is displayed and the
immobilizer-ECU switches to unauthorized
operation, start-prevention mode.
NOTE: Four separate digits must be input to
make up the password.
8. Press the "YES" key to start key ID registration.
9. This will be displayed when the key ID registration
is successful. If an error occurs during key ID
registration, the message "Can't execute" will be
displayed. If the key has already been registered,
"Key ID has been registered" will be displayed.
AC000523AC
AC000530AC
AC000518AC
ACX01558AG
ACX01626AC
ACX01561AD
ACX01562AC
IGNITION SWITCH
CHASSIS ELECTRICAL54A-22
10.The number of keys currently registered will be
displayed. To register an additional key, replace
the ignition key with the next key to be registered
within five seconds and then press the "YES" key.
Key ID registration screen will be displayed, then
register another key.
If key ID registration is complete, press the "NO"
key.
NOTE: A maximum of eight different keys can be
registered.
11.This completes the registration operation. Turn
the ignition switch "LOCK" (OFF) and leave it off
for approximately ten seconds.
12.Check that the engine can be started with each of
the ignition keys.
13.Check that the immobilizer system diagnosis
code and MPI system diagnosis code did not set.
14.Turn the ignition switch to "LOCK" (OFF) position.
15.Disconnect MUT-II.
Registration of additional keys with the
MUT-II
Additional key(s) can be registered with the MUT-II
while keeping all existing key data.
CAUTION
To prevent damage to MUT-II, always turn the
ignition switch to "LOCK" (OFF) position before
connecting or disconnecting MUT-II.
NOTE: To register additional keys with the MUT-II,
no registered keys must be lost.1. Connect MUT-II (MB991502) to the 16-pin
diagnosis connector.
2. Turn the ignition switch to "ON" position.
3. At "System Select," press "YES"
4. Select "Immobilizer," press "YES".
5. Select "Special Func", press "YES".
If diagnosis code No.11 exists, "Can't execute" will
be displayed. Check for diagnosis code
No.11(Refer to P.54A-9.)
ACX01563ACAC304777
Steering shaft
AB
MB991502
AC000522AD
AC000523AC
AC000530AC