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U121B AV CONTROL UNITAV-49
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DescriptionINFOID:0000000001696069
Replace the AV control unit if this DTC is d INFINITI QX56 2008 Factory Service Manual AV
U121B AV CONTROL UNITAV-49
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DescriptionINFOID:0000000001696069
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AV
U121B AV CONTROL UNITAV-49
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DescriptionINFOID:0000000001696069
Replace the AV control unit if this DTC is displayed. Refer to AV-164, "Removal and Installation".
DTC LogicINFOID:0000000001696070
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
U121B HDD-COMM
[U121B] Internal malfunction of AV
control unit (HDD communica-
tion error) is detected. Replace AV control unit. Refer to
AV-
164, "Removal and Installation".
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual AV-50
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121C AV CONTROL UNIT
U121C AV CONTROL UNIT
DescriptionINFOID:0000000001696071
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Remo INFINITI QX56 2008 Factory Service Manual AV-50
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121C AV CONTROL UNIT
U121C AV CONTROL UNIT
DescriptionINFOID:0000000001696071
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Remo](/manual-img/42/57030/w960_57030-230.png)
AV-50
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121C AV CONTROL UNIT
U121C AV CONTROL UNIT
DescriptionINFOID:0000000001696071
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Removal and Installation".
DTC LogicINFOID:0000000001696072
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
U121C HDD-ACCESS
[U121C] Internal malfunction
of AV control unit (HDD access error)
is detected. Replace AV control unit. Refer to
AV-
164, "Removal and Installation".
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual AV
U121D AV CONTROL UNITAV-51
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U121D AV CONTROL UNIT
DescriptionINFOID:0000000001696073
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U121D AV CONTROL UNITAV-51
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DescriptionINFOID:0000000001696073
Replace the AV control unit if this DTC is d](/manual-img/42/57030/w960_57030-231.png)
AV
U121D AV CONTROL UNITAV-51
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U121D AV CONTROL UNIT
DescriptionINFOID:0000000001696073
Replace the AV control unit if this DTC is displayed. Refer to AV-164, "Removal and Installation".
DTC LogicINFOID:0000000001696074
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
U121D DSP CONN
[U121D] Internal malfunction of AV control unit (DSP connection
error) is detected. Replace AV control unit. Refer to
AV-
164, "Removal and Installation".
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual AV-52
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121E AV CONTROL UNIT
U121E AV CONTROL UNIT
DescriptionINFOID:0000000001696075
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Remo INFINITI QX56 2008 Factory Service Manual AV-52
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121E AV CONTROL UNIT
U121E AV CONTROL UNIT
DescriptionINFOID:0000000001696075
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Remo](/manual-img/42/57030/w960_57030-232.png)
AV-52
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U121E AV CONTROL UNIT
U121E AV CONTROL UNIT
DescriptionINFOID:0000000001696075
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Removal and Installation".
DTC LogicINFOID:0000000001696076
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
U121E DSP COMM
[U121E] Internal malfunction of AV control unit (DSP communica-
tion error) is
detected. Replace AV control unit. Refer to
AV-
164, "Removal and Installation".
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual AV
U121F AV CONTROL UNITAV-53
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DescriptionINFOID:0000000001696077
DTC LogicINFOID:0000000001696078
Diagnosis P INFINITI QX56 2008 Factory Service Manual AV
U121F AV CONTROL UNITAV-53
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DescriptionINFOID:0000000001696077
DTC LogicINFOID:0000000001696078
Diagnosis P](/manual-img/42/57030/w960_57030-233.png)
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U121F AV CONTROL UNITAV-53
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DescriptionINFOID:0000000001696077
DTC LogicINFOID:0000000001696078
Diagnosis ProcedureINFOID:0000000001696079
1.CHECK AV CONTROL UNIT POWE R SUPPLY AND GROUND CIRCUIT
Check audio control unit power supply and ground circuit. Refer to AV-63, "
AV CONTROL UNIT : Diagnosis
Procedure".
Is inspection result OK?
YES >> Inspection end.
NO >> Repair malfunctioning parts.
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
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: March 2010
2008 QX56
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![INFINITI QX56 2008 Factory Service Manual AV-62
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U1310 AV CONTROL UNIT
U1310 AV CONTROL UNIT
DescriptionINFOID:0000000001696095
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Remo INFINITI QX56 2008 Factory Service Manual AV-62
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U1310 AV CONTROL UNIT
U1310 AV CONTROL UNIT
DescriptionINFOID:0000000001696095
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Remo](/manual-img/42/57030/w960_57030-242.png)
AV-62
< COMPONENT DIAGNOSIS >[AUDIO SYSTEM]
U1310 AV CONTROL UNIT
U1310 AV CONTROL UNIT
DescriptionINFOID:0000000001696095
Replace the AV control unit if this DTC is displayed. Refer to
AV-164, "Removal and Installation".
DTC LogicINFOID:0000000001696096
Part name Description
AV CONTROL UNIT • 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.
• AV control unit includes audio function and vehicle information function.
• 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-
164, "Removal and Installation".
Revision: March 2010 2008 QX56
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AV CONTROL UNITAV-105
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AV CONTROL UNIT
Reference ValueINFOID:0000000001696141
VALUES ON THE DIAGNOSIS TOOL
CONSULT-III da INFINITI QX56 2008 Factory Service Manual AV
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Reference ValueINFOID:0000000001696141
VALUES ON THE DIAGNOSIS TOOL
CONSULT-III da](/manual-img/42/57030/w960_57030-285.png)
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AV CONTROL UNITAV-105
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AV CONTROL UNIT
Reference ValueINFOID:0000000001696141
VALUES ON THE DIAGNOSIS TOOL
CONSULT-III data monitor item
TERMINAL LAYOUT
PHYSICAL VALUES
Display Item Dis-
play Vehicle status
Remarks
VHCL SPD SIG ON Vehicle speed >0 km/h (0 MPH)
Changes in indication may be delayed. This is
normal.
OFF Vehicle speed =0 km/h (0 MPH)
PKB SIG ON Parking brake is applied.
Changes in indication may be delayed. This is
normal.
OFF Parking brake is released.
ILLUM SIG ON
Block the light beam from the auto
light optical sensor when the light
SW is ON.
—
OFF Expose the auto light optical sensor
to light when the light SW is OFF or
ON.
IGN SIG ON Ignition switch ON
—
OFF Ignition switch in ACC position
REV SIG ON Selector lever in R position
Changes in indication may be delayed. This is
normal.
OFF Selector lever in any position other
than R
ALNIA0670GB
Te r m i n a l
(Wire color) Description
ConditionReference value
(Approx.)
+ – Signal nameInput/
Output
1
(GR/L) Ground Amp. ON signal
OutputIgnition
switch ON —
Battery voltage
2
(LG) 3
(V) Pre-amp. audio signal front
LH
OutputIgnition
switch ON Audio output
SKIB3609E
Revision: March 2010
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![INFINITI QX56 2008 Factory Service Manual AV-110
< ECU DIAGNOSIS >[AUDIO SYSTEM]
AV CONTROL UNIT
79
(G/R) Ground IGN ON or START power
supply InputIgnition
switch ON or
START —
Battery voltage
80
(GR/R) Ground Parking brake signal Input INFINITI QX56 2008 Factory Service Manual AV-110
< ECU DIAGNOSIS >[AUDIO SYSTEM]
AV CONTROL UNIT
79
(G/R) Ground IGN ON or START power
supply InputIgnition
switch ON or
START —
Battery voltage
80
(GR/R) Ground Parking brake signal Input](/manual-img/42/57030/w960_57030-290.png)
AV-110
< ECU DIAGNOSIS >[AUDIO SYSTEM]
AV CONTROL UNIT
79
(G/R) Ground IGN ON or START power
supply InputIgnition
switch ON or
START —
Battery voltage
80
(GR/R) Ground Parking brake signal Input Ignition
switch ON Parking brake ON
0V
Parking brake OFF Battery voltage
81
(G/W) Ground Reverse signal
InputIgnition
switch ON R position
Battery voltage
Other than R position 0V
82
(W/R) Ground Vehicle speed signal (8-
pulse) InputIgnition
switch ON When vehicle speed is ap-
prox. 40 km/h (25MPH)
84
(BR) —
Rear view camera control
signal Input —
— —
92
(W/L) —AV communication signal 2
(H) Input/
Output ——
—
93
(P/B) —AV communication signal 2
(L) Input/
Output ——
—
94
(W/L) —
AV communication signal 1
(H) Input/
Output ——
—
95
(P/B) —
AV communication signal 1
(L) Input/
Output ——
—
96
(L) —CAN–H Input/
Output ——
—
97
(P) —CAN–L Input/
Output ——
—
121 Ground Antenna amp. ON signal Output Ignition
switch ACC —
Battery voltage
122 — Amplified window antenna
signal
Input —
— —
123 — GPS antenna signal — —— —
124 — Shield — —— —
125 — Satellite antenna signal Input Ignition
switch AC C ——
Te
rmi
nal
(Wire color) Description
ConditionReference value
(Approx.)
+ – Signal nameInput/
Output
SKIA6649J
Revision: March 2010 2008 QX56