
ENGINE ELECTRICAL -Charging System16-7
REGULATED VOLTAGE TEST
B
BlueRed
Ignition
switchLoad
FR
L
S
GMB991519
Alternator
BatteryVoltmeterAmmeter
Yellow
Engine-ECU
Black
This test determines whether the voltage regulator
is correctly controlling the alternator output voltage.
(1) Always be sure to check the following before
the test.
DAlternator installation
DCheck that the battery installed in the
vehicle is fully charged.
(Refer to GROUP 54 - Battery.)
DAlternator drive belt tension
(Refer to GROUP 11 - On-vehicle Service.)
DFusible link
DAbnormal 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) Disconnect the alternator output wire from the
alternator “B” terminal.(6) Connect a DC test ammeter with a range of
0 - 100 A in series between the “B” terminal
and the disconnected output wire. (Connect
the (+) lead of the ammeter to the “B” terminal.
Connect the ( - ) lead of the ammeter to the
disconnected output wire.)
(7) Reconnect the negative battery cable.
(8) Connect a tachometer or the MUT-II. (Refer
to GROUP 11 - On-vehicle Service.)
(9) 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.
(10)Turn all lamps and accessories off.
(11) Start the engine.
(12)Increase the engine speed to 2,500 r/min.
(13)Read the value displayed on the voltmeter when
the alternator output current alternator
becomes 10 A or less.

ENGINE ELECTRICAL -Ignition System16-30
WAVEFORM CHECK USING AN ANALYZER
Ignition Secondary Voltage Waveform Check
MEASUREMENT METHOD
1. Clamp the secondary pickup around the spark plug cable.
NOTE
(1) The peak ignition voltage will be reversed when the
spark cables No. 2 and No. 4, or No. 1 and No.
3 cylinders are clamped.
(2) 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.
(3) 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.

ENGINE ELECTRICAL -Ignition System16-31
STANDARD WAVEFORM
Observation Conditions
FunctionSecondary
Pattern heightHigh (or Low)
Pattern selectorRaster
Engine revolutionsCurb idle speed
kV
Secondary
ignition
voltage
waveformIgnition voltage
(point D)
Dwell
section
Point CSpark line (point A)
Wave damping
reduction section
(point B)
Time
Observation Condition (The only change from above condition is the pattern selector.)
Pattern selectorDisplay
Secondary
ignition
voltage
waveformkV
No. 4 cylinder
No. 2 cylinder
ignition noiseNo. 1 cylinderNo. 3 cylinder
ignition noise
Neutral section 0
2Time

MANUAL TRANSMISSION - Troubleshooting
Code No.21 Wheel speed sensor
Code No.22 Wheel speed sensor
Code No.23 Wheel speed sensor
Code No.24 Wheel speed sensor
A diagnosis code corresponding to the open circuit or short circuit of the wheel
speed sensor is output when one wheel speed sensor has detected a vehicle
speed of above 15 km/h, but any one of the remaining three wheel speed
sensors could not detect the vehicle speed.DWheel speed sensor fault
DRotor fault
DWheel bearing fault
DHarness or connector fault
DABS-ECU fault
D4WD-ECU fault
OKNGYES
NO
OK
Measure at 4WD-ECU connector C-44.
DMeasure the ECU terminal voltage.
DIgnition switch: ON
DRotate the tire corresponding to the measured terminal by
one and a half to one rotate per second.
(1) Voltage between terminal 9 and body earth
(2) Voltage between terminal 6 and body earth
(3) Voltage between terminal 7 and body earth
(4) Voltage between terminal 8 and body earth
OK:Changes at 0 V↔5VCheck the following connector:C-44
NG→Repair
Check the following connectors:
NG→Repair
MUT-IIDiagnosis Code
DAre the ABS Diagnosis Code Numbers.11, 12, 13, 14, 21,
22, 23, and 24 output?Refer to GROUP 35B - Troubleshooting.
NG
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions.)
OK
Check the harness between 4WD-ECU and ABS-ECU.
DCheck for open circuit, ground, and short-circuit of the
output line.
NG→Repair
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
NG→Replace the 4WD-ECU
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions.)

MANUAL TRANSMISSION - Troubleshooting
OK OK NG
OK NG
OK OK
OK
NG
Measure at 4WD-ECU connector C-44.
DDisconnect the connector and measure at the harness
side.
(1) Resistance between terminals 9 and 22 (vehicle speed
sensor
(2) Resistance between terminals 6 and 19 (vehicle speed
sensor
(3) Resistance between terminals 7 and 20 (vehicle speed
sensor
(4) Resistance between terminals 8 and 21 (vehicle speed
sensor
OK:1.2 - 1.6 kΩCheck the wheel speed sensor.
(Refer to GROUP 35B - Wheel Speed Sensor.)
NG→Replace
Check the installation of the wheel speed sensor.
NG→Repair
Check the wheel speed sensor and rotor
(Refer to GROUP 35B - Wheel Speed Sensor.)
NG→Repair
Check the wheel beearing. (Refer to GROUP 26 - On-vehicle
Service, and GROUP 27B - Rear Hub Assembly.)
NG→RepairOK
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions.)
Check the following connectors:
C-146, C-111, C-128, A-43
C-146, C-111, C-136, C-147
NG→Repair
Check the harness between the 4WD-ECU and each wheel
speed sensor.
DCheck for open circuit, grounding, and short circuit of the
output line.
DCheck for open circuit and damage of the earth line
NG→Repair
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
NG→Replace the 4WD-ECU.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions) OK
Check the following connector:C-44
NG→Repair
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
NG→Replace the 4WD-ECU
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions.)
Check the wheel speed sensor output voltage. (Refer to
P.22A-44.)

MANUAL TRANSMISSION - Troubleshooting
Code No.25 Wrong-diameter tireProbable cause
Code No.25 is output as wrong-diameter tire when one of the four vehicle
speeds is outside the range of specified values in respect to the average of the
four vehicle speed sensors, when the vehicle speed is above 20 km/h with the
steering wheel in the straight ahead position.
However the warning lamp does not light up.DTire fault
DWheel speed sensor fault
DRotor fault
DWheel bearing fault
DHarness or connector fault
DABS-ECU fault
D4WD-ECU fault
OK NG
OK
Check the following connector:C-44
NG→Repair
Check the following connectors:
NG→Repair OKYES
OK
OK
Check the wheel speed sensor and rotor.
(Refer to GROUP 35B - Wheel Speed Sensor.)
NG→Repair
Check the wheel speed sensor output voltage. (Refer to
GROUP 35B - On-vehicle Service.)OK
Check the wheel speed sensor installation.
NG→Repair
NG
OK
Check the wheel beearing. (Refer to GROUP 26 - On-vehicle
Service, and GROUP 27B - Rear Hub Assembly.)
NG→Repair
OK
Check the following connectors:
C-146, C-111, C-128, A-43
C-146, C-111, C-128, C-136
NG→Repair NG
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions.)
Measure at 4WD-ECU connector C-44.
DMeasure the ECU terminal voltage.
DIgnition switch: ON
DRotate the tire corresponding to the measured terminal by
one and a half to one rotate per second.
(1) Voltage between terminal 9 and body earth
(2) Voltage between terminal 6 and body earth
(3) Voltage between terminal 7 and body earth
(4) Voltage between terminal 8 and body earth
OK:Changes by 0 V↔5V.
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
NG→Replace the 4WD-ECU.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions)
Refer to GROUP 35B - Troubleshooting. (Refer to Diagnosis
Code No.11, 12, 13, 14, 21, 22, 23, and 24.)
Are all four wheels mounted to normal tires?
NO→Repair
Check the harness between the ABS-ECU and each wheel
speed sensor.
DCheck for open circuit and ground of the output line.
DCheck for open circuit and damage of the earth line.
NG→Repair
OK
Check the harness between the 4WD-ECU and
ABS-ECU.
DCheck for open circuit, ground and damage of
the power line.
NG→RepairOK

MANUAL TRANSMISSION - Troubleshooting
OK OK NG
OK NG
OK OK
OK
NG
Measure at 4WD-ECU connector C-44.
DDisconnect the connector and measure at the harness
side.
(1) Resistance between terminals 9 and 22 (vehicle speed
sensor
(2) Resistance between terminals 6 and 19 (vehicle speed
sensor
(3) Resistance between terminals 7 and 20 (vehicle speed
sensor
(4) Resistance between terminals 8 and 21 (vehicle speed
sensor
OK:1.2 - 1.6 kΩCheck the wheel speed sensor.
(Refer to GROUP 35B - Wheel Speed Sensor.)
NG→Replace
Check the installation of the wheel speed sensor.
NG→Repair
Check the wheel speed sensor and rotor.
(Refer to GROUP 35B - Wheel Speed Sensor.)
NG→Repair
Check the wheel beearing. (Refer to GROUP 26 - On-vehicle
Service, and GROUP 27B - Rear Hub Assembly.)
NG→RepairOK
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions)
Check the following connectors:
C-146, C-111, C-128, A-43
C-146, C-111, C-136, C-147
NG→Repair
Check the harness between the 4WD-ECU and each wheel
speed sensor.
DCheck for open circuit and ground of the output line.
DCheck for open circuit and damage of the earth line.
NG→Repair
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
NG→Replace the 4WD-ECU.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions) OK
Check the following connector:C-44
NG→Repair
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
NG→Replace the 4WD-ECU.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions)
Check the wheel speed sensor output voltage. (Refer to
P.22A-44.)

MANUAL TRANSMISSION - Troubleshooting
Code No.26 Wheel speed sensor system (faulty output
signal)Probable cause
Code No.26 is output as output signal error of the wheel speed sensor when
one wheel speed is outside the specified range at the vehicle speed of above
20 km/h.
However, warning lamp will light up.DTire fault
DWheel speed sensor fault
DRotor fault
DWheel bearing fault
DHarness or connector fault
DABS-ECU fault
D4WD-ECU fault
OK NG
OK
Check the following connector:C-44
NG→Repair
Check the following connectors:
NG→Repair OK
Check the harness between the 4WD-ECU and ABS-ECU.
DCheck for open circuit, ground and damage of the power
line.
NG→RepairYES
OK OK
Check the wheel speed sensor and rotor.
(Refer to GROUP 35B - Wheel Speed Sensor.)
NG→RepairCheck the wheel speed sensor output voltage. (Refer to
GROUP 35B - On-vehicle Service.)OK
Check the installation of the wheel speed sensor.
NG→Repair
NG
OK
Check the wheel beearing.
(Refer to GROUP 26 - On-vehicle Service, and GROUP 27B
- Rear Hub Assembly.)
NG→Repair
OK
Check the following connectors:
C-146, C-111, C-128, A-43
C-146, C-111, C-128, C-136
NG→Repair NG
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions)
Measure at 4WD-ECU connector C44.
DMeasure the ECU terminal voltage.
DIgnition switch: ON
DRotate the tire corresponding to the measured terminal by
one and a half to one rotate per second.
(1) Voltage between terminal 9 and the body earth
(2) Voltage between terminal 6 and body earth
(3) Voltage between terminal 7 and body earth
(4) Voltage between terminal 8 and body earth
OK:Changes at 0 V↔5V.
MUT-IIData List
DNo.01 Vehicle speed sensor
DNo.02 Vehicle speed sensor
DNo.03 Vehicle speed sensor
DNo.04 Vehicle speed sensor
OK:The speed meter display and MUT-IIdisplay match.
NG→Replace the 4WD-ECU.
OK→Intermittent malfunction (Refer to GROUP 00 - Points to
Note for Intermittent Malfunctions)Check the harness between the ABS-ECU and each wheel
speed sensor.
DCheck for open circuit, ground, and short circuit of the
output line.
DCheck for open circuit and damage of the earth line.
NG→Repair YES
NO
Refer to GROUP 35B - Troubleshooting.
Are the four wheels mounted to normal tires.
NO→RepairMUT-IIDiagnosis Code
DAre the ABS Diagnosis Code Nos.11, 12, 13, 14, 21, 22,
23, 24 output?