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![INFINITI QX56 2009 Factory Service Manual AV-54
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121B AV CONTROL UNIT
U121B AV CONTROL UNIT
DescriptionINFOID:0000000004110628
Replace the AV control unit if this DTC is displayed. Refer to
AV-168, "Remo INFINITI QX56 2009 Factory Service Manual AV-54
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121B AV CONTROL UNIT
U121B AV CONTROL UNIT
DescriptionINFOID:0000000004110628
Replace the AV control unit if this DTC is displayed. Refer to
AV-168, "Remo](/manual-img/42/57031/w960_57031-239.png)
AV-54
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121B AV CONTROL UNIT
U121B AV CONTROL UNIT
DescriptionINFOID:0000000004110628
Replace the AV control unit if this DTC is displayed. Refer to
AV-168, "Removal and Installation".
DTC LogicINFOID:0000000003776820
Part name Description
AV CONTROL UNIT • Integrates HDD (hard disk dr
ive) allowing map data and music data to be
stored.
• It is the master unit of the MULTI AV system, and it is connected to each control unit by means of communication. It operates each system according to com-
munication signals from the AV control unit.
• The AV control unit includes the audio, hands-free phone, voice control, navi- gation, and vehicle information functions.
• It is connected to ECM and combination meter via CAN communication to ob-
tain necessary information for the vehicle information function.
• It inputs the automatic brightness ON/OFF signals that are required for the dis- play dimming control.
• It inputs the signals for driving status recognition (vehicle speed, reverse and
parking brake).
DTC Display contents of
CONSULT-III DTC Detection Condition
Action to take
U121B HDD-COMM
[U121B] Internal malfunction of AV control unit (HDD communica-
tion error) is
detected. Replace AV control unit. Refer to
AV-
168, "Removal and Installation".
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual AV
U121C AV CONTROL UNITAV-55
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U121C AV CONTROL UNIT
DescriptionINFOID:0000000004110629
Replace the AV control unit if this DTC is d INFINITI QX56 2009 Factory Service Manual AV
U121C AV CONTROL UNITAV-55
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U121C AV CONTROL UNIT
DescriptionINFOID:0000000004110629
Replace the AV control unit if this DTC is d](/manual-img/42/57031/w960_57031-240.png)
AV
U121C AV CONTROL UNITAV-55
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U121C AV CONTROL UNIT
DescriptionINFOID:0000000004110629
Replace the AV control unit if this DTC is displayed. Refer to AV-168, "Removal and Installation".
DTC LogicINFOID:0000000003776822
Part name Description
AV CONTROL UNIT • Integrates HDD (hard disk
drive) allowing map data and music data to be
stored.
• It is the master unit of the MULTI AV system, and it is connected to each control unit by means of communication. It operates each system according to com-
munication signals from the AV control unit.
• The AV control unit includes the audio, hands-free phone, voice control, navi- gation, and vehicle information functions.
• It is connected to ECM and combination meter via CAN communication to ob-
tain necessary information for the vehicle information function.
• It inputs the automatic brightness ON/OFF signals that are required for the dis- play dimming control.
• It inputs the signals for driving status recognition (vehicle speed, reverse and
parking brake).
DTC Display contents of
CONSULT-III DTC Detection Condition
Action to take
U121C HDD-ACCESS
[U121C] Internal malfunction of AV co
ntrol unit (HDD access error)
is detected. Replace AV control unit. Refer to
AV-
168, "Removal and Installation".
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual AV-56
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121D AV CONTROL UNIT
U121D AV CONTROL UNIT
DescriptionINFOID:0000000004110630
Replace the AV control unit if this DTC is displayed. Refer to
AV-168, "Remo INFINITI QX56 2009 Factory Service Manual AV-56
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121D AV CONTROL UNIT
U121D AV CONTROL UNIT
DescriptionINFOID:0000000004110630
Replace the AV control unit if this DTC is displayed. Refer to
AV-168, "Remo](/manual-img/42/57031/w960_57031-241.png)
AV-56
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121D AV CONTROL UNIT
U121D AV CONTROL UNIT
DescriptionINFOID:0000000004110630
Replace the AV control unit if this DTC is displayed. Refer to
AV-168, "Removal and Installation".
DTC LogicINFOID:0000000003776824
Part name Description
AV CONTROL UNIT • Integrates HDD (hard disk dr
ive) allowing map data and music data to be
stored.
• It is the master unit of the MULTI AV system, and it is connected to each control unit by means of communication. It operates each system according to com-
munication signals from the AV control unit.
• The AV control unit includes the audio, hands-free phone, voice control, navi- gation, and vehicle information functions.
• It is connected to ECM and combination meter via CAN communication to ob-
tain necessary information for the vehicle information function.
• It inputs the automatic brightness ON/OFF signals that are required for the dis- play dimming control.
• It inputs the signals for driving status recognition (vehicle speed, reverse and
parking brake).
DTC Display contents of
CONSULT-III DTC Detection Condition
Action to take
U121D DSP CONN
[U121D] Internal malfunction of AV control unit (DSP connection
error) is detected. Replace AV control unit. Refer to
AV-
168, "Removal and Installation".
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual AV
U121E AV CONTROL UNITAV-57
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U121E AV CONTROL UNIT
DescriptionINFOID:0000000004110631
Replace the AV control unit if this DTC is d INFINITI QX56 2009 Factory Service Manual AV
U121E AV CONTROL UNITAV-57
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U121E AV CONTROL UNIT
DescriptionINFOID:0000000004110631
Replace the AV control unit if this DTC is d](/manual-img/42/57031/w960_57031-242.png)
AV
U121E AV CONTROL UNITAV-57
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U121E AV CONTROL UNIT
DescriptionINFOID:0000000004110631
Replace the AV control unit if this DTC is displayed. Refer to AV-168, "Removal and Installation".
DTC LogicINFOID:0000000003776826
Part name Description
AV CONTROL UNIT • Integrates HDD (hard disk
drive) allowing map data and music data to be
stored.
• It is the master unit of the MULTI AV system, and it is connected to each control unit by means of communication. It operates each system according to com-
munication signals from the AV control unit.
• The AV control unit includes the audio, hands-free phone, voice control, navi- gation, and vehicle information functions.
• It is connected to ECM and combination meter via CAN communication to ob-
tain necessary information for the vehicle information function.
• It inputs the automatic brightness ON/OFF signals that are required for the dis- play dimming control.
• It inputs the signals for driving status recognition (vehicle speed, reverse and
parking brake).
DTC Display contents of
CONSULT-III DTC Detection Condition
Action to take
U121E DSP COMM
[U121E] Internal malfunction of AV control unit (DSP communica-
tion error) is detected. Replace AV control unit. Refer to
AV-
168, "Removal and Installation".
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual AV-58
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121F AV CONTROL UNIT
U121F AV CONTROL UNIT
DescriptionINFOID:0000000004110660
DTC LogicINFOID:0000000003776828
Diagnosis ProcedureINFOID:0000000003776829
1 INFINITI QX56 2009 Factory Service Manual AV-58
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121F AV CONTROL UNIT
U121F AV CONTROL UNIT
DescriptionINFOID:0000000004110660
DTC LogicINFOID:0000000003776828
Diagnosis ProcedureINFOID:0000000003776829
1](/manual-img/42/57031/w960_57031-243.png)
AV-58
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121F AV CONTROL UNIT
U121F AV CONTROL UNIT
DescriptionINFOID:0000000004110660
DTC LogicINFOID:0000000003776828
Diagnosis ProcedureINFOID:0000000003776829
1.CHECK AV CONTROL UNIT POWER SUPPLY AND GROUND CIRCUIT
Check AV control unit power supply and ground circuit. Refer to AV-68, "
AV CONTROL UNIT : Diagnosis Pro-
cedure".
Is inspection result OK?
YES >> Inspection End.
NO >> Repair malfunctioning parts.
Part name Description
AV CONTROL UNIT • Integrates HDD (hard disk dr
ive) allowing map data and music data to be
stored.
• It is the master unit of the MULTI AV system, and it is connected to each control
unit by means of communication. It operates each system according to com-
munication signals from the AV control unit.
• The AV control unit includes the audio, hands-free phone, voice control, navi-
gation, and vehicle information functions.
• It is connected to ECM and combination meter via CAN communication to ob- tain necessary information for the vehicle information function.
• It inputs the automatic brightness ON/OFF signals that are required for the dis- play dimming control.
• It inputs the signals for driving status recognition (vehicle speed, reverse and parking brake).
DTC Display contents of
CONSULT-III DTC Detection Condition
Action to take
U121F INTERNAL COMM
[U121F] Internal malfunction of AV control unit (internal communi-
cation error)
is detected. AV control unit power supply and
ground circuit.
Revision: December 20092009 QX56
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U1220 AV CONTROL UNITAV-59
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U1220 AV CONTROL UNIT
DescriptionINFOID:0000000004110661
Replace the AV control unit if this DTC is d INFINITI QX56 2009 Factory Service Manual AV
U1220 AV CONTROL UNITAV-59
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U1220 AV CONTROL UNIT
DescriptionINFOID:0000000004110661
Replace the AV control unit if this DTC is d](/manual-img/42/57031/w960_57031-244.png)
AV
U1220 AV CONTROL UNITAV-59
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U1220 AV CONTROL UNIT
DescriptionINFOID:0000000004110661
Replace the AV control unit if this DTC is displayed. Refer to AV-168, "Removal and Installation".
DTC LogicINFOID:0000000003776831
DTC DETECTION LOGIC
Part name Description
AV CONTROL UNIT • Integrates HDD (hard disk
drive) allowing map data and music data to be
stored.
• It is the master unit of the MULTI AV system, and it is connected to each control unit by means of communication. It operates each system according to com-
munication signals from the AV control unit.
• The AV control unit includes the audio, hands-free phone, voice control, navi- gation, and vehicle information functions.
• It is connected to ECM and combination meter via CAN communication to ob-
tain necessary information for the vehicle information function.
• It inputs the automatic brightness ON/OFF signals that are required for the dis- play dimming control.
• It inputs the signals for driving status recognition (vehicle speed, reverse and
parking brake).
DTC CONSULT-III display Detection conditionAction to take
U1220 XM SERIAL COMM
[U1220] An internal malfunction is detected in AV control unit (sat-
ellite radio tuner communication malfunction). Replace AV control unit. Refer
to
AV-168, "
Removal and Instal-
lation".
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual AV
U1310 AV CONTROL UNITAV-67
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U1310 AV CONTROL UNIT
DescriptionINFOID:0000000004110662
Replace the AV control unit if this DTC is d INFINITI QX56 2009 Factory Service Manual AV
U1310 AV CONTROL UNITAV-67
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U1310 AV CONTROL UNIT
DescriptionINFOID:0000000004110662
Replace the AV control unit if this DTC is d](/manual-img/42/57031/w960_57031-252.png)
AV
U1310 AV CONTROL UNITAV-67
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U1310 AV CONTROL UNIT
DescriptionINFOID:0000000004110662
Replace the AV control unit if this DTC is displayed. Refer to AV-168, "Removal and Installation".
DTC LogicINFOID:0000000003776846
Part name Description
AV CONTROL UNIT • Integrates HDD (hard disk
drive) allowing map data and music data to be
stored.
• It is the master unit of the MULTI AV system, and it is connected to each control unit by means of communication. It operates each system according to com-
munication signals from the AV control unit.
• The AV control unit includes the audio, hands-free phone, voice control, navi- gation, and vehicle information functions.
• It is connected to ECM and combination meter via CAN communication to ob-
tain necessary information for the vehicle information function.
• It inputs the automatic brightness ON/OFF signals that are required for the dis- play dimming control.
• It inputs the signals for driving status recognition (vehicle speed, reverse and
parking brake).
DTC Display contents of
CONSULT-III DTC Detection Condition
Action to take
U1310 CONTROL UNIT (AV)
[U1310] An initial diagnosis error is detected in AV communication
circuit. Replace AV control unit. Refer to
AV-
168, "Removal and Installation".
Revision: December 20092009 QX56
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![INFINITI QX56 2009 Factory Service Manual AV
POWER SUPPLY AND GROUND CIRCUITAV-75
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VIDEO MONITOR : Diagnosis ProcedureINFOID:0000000003776855
1.CHECK POWER SUPPLY CIRCUIT
Che INFINITI QX56 2009 Factory Service Manual AV
POWER SUPPLY AND GROUND CIRCUITAV-75
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VIDEO MONITOR : Diagnosis ProcedureINFOID:0000000003776855
1.CHECK POWER SUPPLY CIRCUIT
Che](/manual-img/42/57031/w960_57031-260.png)
AV
POWER SUPPLY AND GROUND CIRCUITAV-75
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VIDEO MONITOR : Diagnosis ProcedureINFOID:0000000003776855
1.CHECK POWER SUPPLY CIRCUIT
Check voltage between video monitor harness connector R202 and
ground.
Does specified voltage exist?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect the video monitor connector R202 and the DVD player connector M205.
3. Check continuity between the video monitor harness connector R202 (A) and the DVD player connector M205 (B).
4. Check continuity between video monitor harness connector R202 (A) and ground.
Are continuity test results as specified?
YES >> Check DVD player power and ground supply. Refer to AV-68, "AV CONTROL UNIT : Diagnosis
Procedure".
NO >> Repair harness or connector.
3.CHECK GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect video monitor connector.
3. Check continuity between video monitor harness connector R202 and ground.
Does continuity exist?
YES >> Inspection end.
NO >> Repair harness or connector.
MICROPHONE
Signal name Connector Terminal Ignition switch
position Value (Approx.)
Display B+ R202 11
ACC 12V
12
ALNIA0328GB
AB Continuity
Connector Terminal Connector Terminal
R202 11
M205 9
Ye s
12 25
A -Con tin uit y
Connector Terminal
R202 11
Ground No
12
AWLIA1600ZZ
Connector Terminal Ignition switch position Continuity
R202 1
OFF Yes
2
ALNIA0329GB
Revision: December 20092009 QX56