INFINITI QX56 2008 Factory Service Manual

CHG
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM
CHG-9
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POWER GENERATION VOLTAG
E VARIABLE CONTROL SYSTEM
System DiagramINFOID:0000000001696181
System DescriptionINFOID:0000000001696182
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:0000000001696183
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: March 2010
2008 QX56

CHG-10
< COMPONENT DIAGNOSIS >
CHARGING SYSTEM PRELIMINARY INSPECTION
COMPONENT DIAGNOSIS
CHARGING SYSTEM PRELIMINARY INSPECTION
Inspection ProcedureINFOID:0000000001696184
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: March 2010 2008 QX56

CHG
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM OPERATION
INSPECTION
CHG-11
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POWER GENERATION VOLTAGE VARI
ABLE CONTROL SYSTEM OPER-
ATION INSPECTION
Inspection ProcedureINFOID:0000000001696185
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
1. Turn ignition switch OFF.
2. Disconnect generator connector E205 and IPDM E/R connector E122.
3. Check continuity between generator harness connector E205 (A) terminal 4 and IPDM E/R harness connector E122 (B) termi-
nal 37. “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 %
AB
Continuity
Connector Terminal Connector Terminal
E205 4E122 37Yes
ALMIA0196ZZ
Revision: March 2010 2008 QX56

CHG-12
< COMPONENT DIAGNOSIS >
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM OPERATION
INSPECTION
4. Check continuity between generator harnes s connector E122 (A) terminal 4 and ground.
Are the continuity test results as specified?
YES >> Replace IPDM E/R.
NO >> Repair harness or connector between IPDM E/R and generator.
A —Contin u it y
Connector Terminal
E205 4Ground No
Revision: March 2010 2008 QX56

CHG
B TERMINAL CIRCUITCHG-13
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B TERMINAL CIRCUIT
DescriptionINFOID:0000000001696186
The terminal “1” circuit supplies power to charge the battery and operate the vehicles electrical system.
Diagnosis ProcedureINFOID:0000000001696187
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 Technical Service Bulletin.
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: March 2010 2008 QX56

CHG-14
< COMPONENT DIAGNOSIS >
L TERMINAL CIRCUIT
L TERMINAL CIRCUIT
DescriptionINFOID:0000000001696188
The terminal “2” (L) circuit controls the charge warning lamp. The charge warning lamp illuminates when the
ignition switch is set to ON or START. When the generator is providing sufficient voltage with the engine run-
ning, the charge warning lamp will go off. If the c harge warning lamp illuminates with the engine running, a
malfunction is indicated.
Diagnosis ProcedureINFOID:0000000001696189
1.CHECK CHARGE WARNING LAMP CIRCUIT CONNECTION
Verify generator connector E205 terminal 2 is clean and tight.
Is the connection secure?
YES >> GO TO 2
NO >> Repair the connection. Confirm repair by per forming complete Starting/Charging system test.
Refer to Technical Service Bulletin.
2.CHECK CHARGE WARNING LAMP CIRCUIT
1. Disconnect generator connector E205.
2. Apply ground to generator harness connector E205 terminal 2 with the ignition switch in the ON position.
Does the charge lamp illuminate?
YES >> Check generator function. Refer to CHG-5, "Work Flow".
NO >> GO TO 3
3.CHECK HARNESS CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect the generator connector E205 and combination meter connector M24.
3. Check continuity between generator harness connector E205 (A) terminal 2 and combination meter harness connector M24
(B) terminal 6.
4. Check continuity between generator harness connector E205 (A) terminal 2 and ground.
Are the continuity results as specified?
YES >> Replace the combination meter. Refer to MWI-76, "Removal and Installation".
NO >> Repair the harness or connector. Charge lamp should illuminate
ALMIA0200ZZ
AB
Continuity
Connector Terminal Connector Terminal
E205 2M24 6Yes
A —
Continuity
Connector Terminal
E205 2Ground No
AWMIA0596ZZ
Revision: March 2010 2008 QX56

CHG
S TERMINAL CIRCUITCHG-15
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S TERMINAL CIRCUIT
DescriptionINFOID:0000000001696190
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:0000000001696191
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 Technical Service Bulletin.
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: March 2010 2008 QX56

CHG-16
< COMPONENT DIAGNOSIS >
CHARGING SYSTEM
CHARGING SYSTEM
Wiring DiagramINFOID:0000000001696192
AAMWA0085GB
Revision: March 20102008 QX56

CHG
CHARGING SYSTEMCHG-17
< COMPONENT DIAGNOSIS >
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AAMIA0176GB
Revision: March 2010
2008 QX56

CHG-18
< COMPONENT DIAGNOSIS >
CHARGING SYSTEM
AWMIA0080GB
Revision: March 20102008 QX56