INFINITI QX56 2011 Factory Service Manual

CHG-18
< BASIC INSPECTION >
POWER GENERATION VOLTAGE VARIABLE CONTROL SYSTEM OPERATION
INSPECTION
Is the inspection result normal?
YES >> Replace IPDM E/R.
NO >> Repair harness or connector between IPDM E/R and alternator.
Alternator harness connector
GroundContinuity
Connector Terminal
E205 5 Not existed
Revision: 2010 May2011 QX56

CHG
B TERMINAL CIRCUITCHG-19
< DTC/CIRCUIT DIAGNOSIS >
C
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G H
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B A
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DTC/CIRCUIT DIAGNOSIS
B TERMINAL CIRCUIT
DescriptionINFOID:0000000006274868
“B” terminal circuit supplies power to charge the bat
tery and to operate the vehicle’s electrical system.
Diagnosis ProcedureINFOID:0000000006274869
1.CHECK “B” TERMINAL CONNECTION
1. Turn ignition switch OFF.
2. Check that “B” terminal is clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair “B” terminal connection. Confirm repair by performing complete Starting/Charging system test. Refer to Technical Service Bulletin.
2.CHECK “B” TERMINAL CIRCUIT
Check voltage between alternator “B” terminal and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Check harness for open between alternator and fusible link.
3.CHECK “B” TERMINAL CONNECT ION (VOLTAGE DROP TEST)
1. Start engine, then engine running at idle and warm.
2. Check voltage between battery positive terminal and alternator “B” terminal.
Is the inspection result normal?
YES >> “B” terminal circuit is normal. Refer to CHG-13, "Work Flow".
NO >> Check harness between battery and alternator for poor continuity.
(+)
(–) Voltage
Alternator “B” terminal
E203 1 Ground Battery voltage
(+) (–)
Voltage (V)
(Approx.)
Alternator “B” terminal Terminal
Battery positive terminal E203 1 Less than 0.2
Revision: 2010 May2011 QX56

CHG-20
< DTC/CIRCUIT DIAGNOSIS >
L TERMINAL CIRCUIT (OPEN)
L TERMINAL CIRCUIT (OPEN)
DescriptionINFOID:0000000006274870
The “L” terminal circuit controls the charge warning lamp. The charge warning lamp illuminates when the igni-
tion switch is set to ON or START. When the alternat or is providing sufficient voltage with the engine running,
the charge warning lamp will go off. If the charge warn ing lamp illuminates with the engine running, a malfunc-
tion is indicated.
Diagnosis ProcedureINFOID:0000000006274871
1.CHECK “L” TERMINAL CONNECTION
1. Turn ignition switch OFF.
2. Check that “L” terminal is clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair “L” terminal connection. Confirm repair by performing complete Starting/Charging system test. Refer to Technical Service Bulletin.
2.CHECK “L” TERMIN AL CIRCUIT (OPEN)
1. Disconnect alternator connector.
2. Apply ground to alternator harness connector terminal.
3. Check condition of the charge warning lamp with the ignition switch in the ON position.
Does it illuminate?
YES >> “L” terminal circuit is normal. Refer to CHG-13, "Work Flow".
NO >> GO TO 3.
3.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
1. Disconnect the battery cable from the negative terminal.
2. Disconnect the combination meter connector.
3. Check continuity between alternator harness connector and combination meter harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair the harness or connector.
4.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
Check continuity between combination me ter harness connector and fuse block (J/B).
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair the harness or connector.
5.CHECK POWER SUPPLY CIRCUIT
(+) (–) Condition Charge warning lamp
Alternator
Connector Terminal E205 3 Ground Ignition switch ON ON
Alternator Combination meter Continuity
Connector Terminal Connector Terminal
E205 3 M34 25 Existed
Combination meter Fuse block (J/B) Continuity
Connector Terminal Connector Terminal
M34 2 M1 2A Existed
Revision: 2010 May2011 QX56

CHG
L TERMINAL CIRCUIT (OPEN)CHG-21
< DTC/CIRCUIT DIAGNOSIS >
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B A
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1. Connect the battery cable to the negative terminal.
2. Check voltage between combination meter harness connector and ground.
Is the inspection result normal?
YES >> Replace combination meter.
NO >> Inspect the power supply circuit. Refer to
PG-89, "
Wiring Diagram - IGNITION POWER SUPPLY -
".
(+)
(–) Condition Voltage
Combination meter
Connector Terminal M34 2 Ground Ignition switch ON Battery voltage
Revision: 2010 May2011 QX56

CHG-22
< DTC/CIRCUIT DIAGNOSIS >
L TERMINAL CIRCUIT (SHORT)
L TERMINAL CIRCUIT (SHORT)
DescriptionINFOID:0000000006274872
The “L” terminal circuit controls the charge warning lamp. The charge warning lamp illuminates when the igni-
tion switch is set to ON or START. When the alternat or is providing sufficient voltage with the engine running,
the charge warning lamp will go off. If the charge warn ing lamp illuminates with the engine running, a malfunc-
tion is indicated.
Diagnosis ProcedureINFOID:0000000006274873
1.CHECK “L” TERMINAL CIRCUIT (SHORT)
1. Turn ignition switch OFF.
2. Disconnect alternator connector.
3. Turn ignition switch ON.
Does charge warning lamp illuminate?
YES >> GO TO 2.
NO >> Refer to CHG-13, "
Work Flow".
2.CHECK HARNESS CONTI NUITY (SHORT CIRCUIT)
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Disconnect combination meter connector.
4. Check continuity between combination meter harness connector and ground.
Is the inspection result normal?
YES >> Replace combination meter.
NO >> Repair the harness or connector.
Combination meter
GroundContinuity
Connector Terminal
M34 25 Not existed
Revision: 2010 May2011 QX56

CHG
S TERMINAL CIRCUITCHG-23
< DTC/CIRCUIT DIAGNOSIS >
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S TERMINAL CIRCUIT
DescriptionINFOID:0000000006274874
The output voltage of the alternator is controlled by t
he IC voltage regulator at the “S” terminal detecting the
input voltage.
The “S” terminal circuit detects the battery voltage to adjust the alternator output voltage with the IC voltage
regulator.
Diagnosis ProcedureINFOID:0000000006274875
1.CHECK “S” TERMINAL CONNECTION
1. Turn ignition switch OFF.
2. Check if “S” terminal is clean and tight.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair “S” terminal connection. Confirm repair by performing complete Starting/Charging system test. Refer to Technical Service Bulletin.
2.CHECK “S” TERMINAL CIRCUIT
Check voltage between alternator harness connector and ground.
Is the inspection result normal?
YES >> Refer to CHG-13, "Work Flow".
NO >> Check harness for open between alternator and fuse.
(+)
(–) Voltage
Alternator
Connector Terminal E205 4 Ground Battery voltage
Revision: 2010 May2011 QX56

CHG-24
< SYMPTOM DIAGNOSIS >
CHARGING SYSTEM
SYMPTOM DIAGNOSIS
CHARGING SYSTEM
Symptom TableINFOID:0000000006274876
Symptom Reference
Discharged battery
Refer to CHG-13, "
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: 2010 May2011 QX56

CHG
ALTERNATORCHG-25
< REMOVAL AND INSTALLATION >
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B A
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REMOVAL AND INSTALLATION
ALTERNATOR
Exploded ViewINFOID:0000000006274877
REMOVAL
DISASSEMBLY
1. Alternator bracket 2. Alternator bracket mounting bolt 3. “B” terminal harness
4. “B” terminal nut 5. Alternator connector 6. Alternator
7. Alternator stay 8. Alternator mounting bolt (lower) 9. Alternator stay mounting bolt
10. Ground harness 11. Alternator mounting bolt (upper)
Refer to
GI-4, "
Components" for symbols in the figure.
JMMIA0361GB
Revision: 2010 May2011 QX56

CHG-26
< REMOVAL AND INSTALLATION >
ALTERNATOR
Type: A002TX1491
Removal and InstallationINFOID:0000000006274878
REMOVAL
1. Disconnect the battery cable from the negative terminal. Refer to PG-164, "Removal and Installation".
2. Remove front under cover. Refer to EXT-25, "
Removal and Installation".
3. Remove drive belt. Refer to EM-20, "
Removal and Installation".
4. Disconnect engine oil pressure switch connector (A) and alter- nator connector (B).
5. Remove harness bracket bolt (C).
6. Remove “B” terminal nut (D) and disconnect “B” terminal har- ness.
JMMIA0363GB
1. Rear bearing 2. Rotor assembly 3. Retainer
4. Front bearing 5. Front bracket assembly 6. Pulley
7. Pulley nut 8. Stator assembly 9. IC voltage regulator assembly
10. Diode assembly 11. Rear bracket assembly 12. Terminal set
Refer to GI-4, "
Components" for symbols in the figure.
JMMIA0364ZZ
Revision: 2010 May2011 QX56

CHG
ALTERNATORCHG-27
< REMOVAL AND INSTALLATION >
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7. Remove ground harness mounting bolt.
8. Remove alternator mounting bolt (lower), and then alternator mounting bolt (upper).
9. Remove A/T fluid cooler tube (1) from fan shroud (2).
10. Move A/T fluid cooler tube (1) and secure work space.
11. Remove alternator assembly
(2) from underneath the vehicle.
INSTALLATION
Note the following items, and then install in the reverse order of removal.
CAUTION:
 Be careful to tighten “B” terminal nut carefully.
 Install alternator, and check tension of belt. Refer to EM-20, "
Checking".
 For this model, the power genera tion voltage variable control system that controls the power gener-
ation voltage of the alternator has been adopted. Therefore, the power generation voltage variable
control system operation inspectio n should be performed after replacing the alternator, and then
make sure that the system operates normally. Refer to CHG-17, "
Inspection Procedure".
 When installing alternator br acket, tighten mounting bolts in
numerical order as shown in the figure.
JMMIA0365ZZ
JMMIA0366ZZ
JMMIA0367ZZ
JMMIA0456ZZ
Revision: 2010 May2011 QX56