Page 746 of 4210
CHG-4
< PREPARATION >
PREPARATION
PREPARATION
PREPARATION
Special Service ToolINFOID:0000000005146548
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Commercial Service ToolINFOID:0000000005146549
Tool number
(Kent-Moore No.)
Tool name Description
—
(—) Model GR-8
Multitasking Battery Diagnostic Sta-
tion Tests batteries, starting and charging sys-
tems.
For operating instructions, refer to diagnostic
station instruction manual.
AWIIA1239ZZ
Tool name
Description
Power tool Loosening bolts and nuts
PBIC0190E
Revision: April 20092010 QX56
Page 748 of 4210

CHG-6
< FUNCTION DIAGNOSIS >
CHARGING SYSTEM
FUNCTION DIAGNOSIS
CHARGING SYSTEM
System DiagramINFOID:0000000005146551
System DescriptionINFOID:0000000005146552
The generator provides DC voltage to operate the vehicle's electrical system and to keep the battery charged.
The voltage output is controlled by the IC regulator.
Component DescriptionINFOID:0000000005146553
ALMIA0207GB
Component part Description
Generator Terminal “1”
Refer to CHG-11, "
Description".
Terminal “2” Refer to CHG-12, "
Description".
Terminal “3” Refer to CHG-13, "
Description".
Terminal “4” Used for the power generation voltage variable control system.
Refer to
CHG-7, "
System Description".
Combination meter (C harge warning lamp) The IC regulator warning function activates to illuminate the
charge warning lamp if any of the following symptoms occur while
generator is operating:
• Excessive voltage is produced.
• No voltage is produced.
IPDM E/R Used for the power generation voltage variable control system.
Refer to
CHG-7, "
System Description".
Revision: April 20092010 QX56
Page 749 of 4210

CHG
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM
CHG-7
< FUNCTION DIAGNOSIS >
C
D E
F
G H
I
J
K L
B A
O P
N
POWER GENERATION VOLTAG
E VARIABLE CONTROL SYSTEM
System DiagramINFOID:0000000005146554
System DescriptionINFOID:0000000005146555
Power generation variable voltage control system has been adopted. By varying the voltage to the generator,
engine load due to power generation of the generator is reduced and fuel consumption is decreased.
NOTE:
When any malfunction is detected in the power generat ion variable voltage control system, power generation
is performed according to the characterist ic of the IC regulator in the generator.
Component DescriptionINFOID:0000000005146556
ALMIA0057GB
Component part Description
Battery current sensor The battery current sensor is installed on the battery cable at the
negative terminal. The battery current sensor detects the charg-
ing/discharging current of the battery and sends a voltage signal
to the ECM according to the current value detected.
ECM The battery current sensor detects the charging/discharging cur-
rent of the battery. The ECM judges the battery condition based on
this signal.
The ECM judges whether to request more output via the power
generation voltage variable control according to the battery condi-
tion.
When performing the power generation voltage variable control,
the ECM calculates the target power generation voltage according
to the battery condition and sends the calculated value as the pow-
er generation command value to the IPDM E/R.
IPDM E/R The IPDM E/R converts the received power generation command
value into a pulse width modulated (PWM) command signal and
sends it to the IC regulator.
Generator (IC regulator) The IC regulator controls the power generation voltage by the tar-
get power generation voltage based on the received PWM com-
mand signal.
When there is no PWM command signal, the generator performs
the normal power generation according to the characteristic of the
IC regulator.
Revision: April 20092010 QX56
Page 750 of 4210

CHG-8
< COMPONENT DIAGNOSIS >
CHARGING SYSTEM PRELIMINARY INSPECTION
COMPONENT DIAGNOSIS
CHARGING SYSTEM PRELIMINARY INSPECTION
Inspection ProcedureINFOID:0000000005146557
1.CHECK BATTERY TERMINALS CONNECTION
Check if battery terminals are clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair battery terminals connection.
2.CHECK FUSE
Check for blown fuse and fusible link.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Be sure to eliminate cause of malfunction before installing new fuse or fusible link.
3.CHECK GENERATOR GROUND TERMINAL CONNECTION
Verify connector E206 terminal 5 (generator ground harness) is clean and tight.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair connection.
4.CHECK DRIVE BELT TENSION
Check drive belt tension. Refer to EM-13, "
Checking Drive Belts".
Is the inspection result normal?
YES >> Inspection End.
NO >> Repair as needed.
Unit Power source (Power supply terminals) Fuse or Fusible Link
Generator Battery (terminal 3)
Fuse 30
Battery (terminal 1) Fusible Link A
Combination meter Ignition switch ON (terminal 2) Fuse 14
Revision: April 20092010 QX56
Page 751 of 4210

CHG
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM OPERATION
INSPECTION
CHG-9
< COMPONENT DIAGNOSIS >
C
DE
F
G H
I
J
K L
B A
O P
N
POWER GENERATION VOLTAGE VARI
ABLE CONTROL SYSTEM OPER-
ATION INSPECTION
Diagnosis ProcedureINFOID:0000000005146558
Regarding Wiring Diagram information, refer to CHG-14, "Wiring Diagram".
CAUTION:
When performing this inspection, always use a charged battery that has completed the battery inspec-
tion. (When the charging rate of the battery is low, the response speed of the voltage change will
become slow. This can cause an incorrect inspection.)
1.CHECK ECM (CONSULT-III)
Perform ECM self-diagnosis with CONSULT-III. Refer to EC-63, "
CONSULT-III Function (ENGINE)".
Self
-diagnostic results content
No malfunction detected>> GO TO 2.
Malfunction detected>> Check applicable parts, and repair or replace corresponding parts.
2.CHECK OPERATION OF POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM
1. Connect CONSULT-III and start the engine.
2. The selector lever is in “P” or “N” position and a ll of the electric loads and A/C, etc. are turned OFF.
3. Select “ALTERNATOR DUTY” in “Active Test” of “ENGINE”, and then check the value of “BATTERY
VOLT” monitor when DUTY value of “ALTERNATOR DUTY” is set to 40.0 %.
4. Check the value of “BATTERY VOLT” monitor when DUTY value of “ALTERNATOR DUTY” is set to 80.0%.
Is the measurement val ue within specification?
YES >> Inspection End.
NO >> GO TO 3.
3.CHECK IPDM E/R (CONSULT-III)
Perform IPDM E/R self-diagnosis with CONSULT-III. Refer to PCS-14, "
CONSULT - III Function (IPDM E/R)".
Self
-diagnostic results content
No malfunction detected>> GO TO 4.
Malfunction detected>> Check applicable parts, and repair or replace corresponding parts.
4.CHECK HARNESS BETWEEN GE NERATOR AND IPDM E/R
“BATTERY VOLT”
2 seconds after setting the
DUTY value of “ALTERNA-
TOR DUTY” to 40.0 %
: 12 - 13.6 V
“BATTERY VOLT”
20 seconds after setting
the DUTY value of “ALTER-
NATOR DUTY” to 80.0 % : +0.5 V or more against
the value of “BATTERY
VOLT” monitor when
DUTY value is 40.0 %
Revision: April 20092010 QX56
Page 753 of 4210

CHG
B TERMINAL CIRCUITCHG-11
< COMPONENT DIAGNOSIS >
C
DE
F
G H
I
J
K L
B A
O P
N
B TERMINAL CIRCUIT
DescriptionINFOID:0000000005146559
The terminal “1” circuit supplies power to charge the battery and operate the vehicles electrical system.
Diagnosis ProcedureINFOID:0000000005146560
Regarding Wiring Diagram information, refer to
CHG-14, "Wiring Diagram".
1.CHECK TERMINAL “1” CONNECTION
1. Turn ignition switch OFF.
2. Verify terminal “1” is clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair terminal “1” connection. Confirm repa ir by performing complete Starting/Charging system
test. Refer to diagnostic station instruction manual.
2.CHECK TERMINAL “1” CIRCUIT
Check voltage between generator connector E204 terminal 1 and
ground.
Is voltage reading as specified?
YES >> GO TO 3.
NO >> Check harness for open between generator and fusible link.
3.CHECK TERMINAL “1” CONNECTION (VOLTAGE DROP TEST)
1. Start engine, then engine running at idle and warm.
2. Check voltage between battery positive terminal and generator connector E204 terminal 1.
Is the voltage reading as specified?
YES >> Terminal “1” circuit is normal. Refer to CHG-5, "Work
Flow".
NO >> Check harness between battery and generator for high resistance.
(+) (-) Voltage
Connector Terminal
E204 1Ground Battery voltage
ALMIA0197ZZ
(+)
(-)Voltage
Connector Terminal
E204 1 Battery positive terminal Less than 0.2V
ALMIA0198ZZ
Revision: April 20092010 QX56
Page 755 of 4210

CHG
S TERMINAL CIRCUITCHG-13
< COMPONENT DIAGNOSIS >
C
DE
F
G H
I
J
K L
B A
O P
N
S TERMINAL CIRCUIT
DescriptionINFOID:0000000005146563
The output voltage of the generator is controlled by the IC
regulator at terminal “3” (S) detecting the input volt-
age. Terminal “3” circuit detects the battery voltage to adjust the generator output voltage with the IC regulator.
Diagnosis ProcedureINFOID:0000000005146564
Regarding Wiring Diagram information, refer to CHG-14, "Wiring Diagram".
1.CHECK VOLTAGE REGULATOR CIRCUIT CONNECTION
Check to see if connector E205 terminal 3 is clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair terminal connection. Confirm repair by performing complete Starting/Charging system test.
Refer to diagnostic station instruction manual.
2.CHECK VOLTAGE REGULATOR CIRCUIT
Check voltage between generator harness connector E205 terminal
3 and ground.
Does battery voltage exist?
YES >> Refer to CHG-5, "Work Flow".
NO >> Check harness for open between generator and fuse. 3 - ground
Battery voltage
ALMIA0201ZZ
Revision: April 20092010 QX56
Page 762 of 4210
CHG-20
< SYMPTOM DIAGNOSIS >
CHARGING SYSTEM
SYMPTOM DIAGNOSIS
CHARGING SYSTEM
Symptom TableINFOID:0000000005146566
SymptomReference
Battery discharged
Refer to CHG-5, "
Work Flow".
The charge warning lamp does not illuminate when the ignition
switch is set to ON.
The charge warning lamp does not turn OFF after the engine
starts.
The charging warning lamp turns ON when increasing the engine
speed.
Revision: April 20092010 QX56