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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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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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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.
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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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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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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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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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AV CONTROL UNITAV-109
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AV CONTROL UNIT
Reference ValueINFOID:0000000003776891
VALUES ON THE DIAGNOSIS TOOL
CONSULT-III da INFINITI QX56 2009 Factory Service Manual AV
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AV CONTROL UNIT
Reference ValueINFOID:0000000003776891
VALUES ON THE DIAGNOSIS TOOL
CONSULT-III da](/manual-img/42/57031/w960_57031-294.png)
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AV CONTROL UNIT
Reference ValueINFOID:0000000003776891
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
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< 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
(G) Ground Parking brake signal Input Ign INFINITI QX56 2009 Factory Service Manual AV-114
< 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
(G) Ground Parking brake signal Input Ign](/manual-img/42/57031/w960_57031-299.png)
AV-114
< 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
(G) 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
(L/W) —AV communication signal 2
(H) Input/
Output ——
—
93
(B/P) —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 ——
T
erminal
(Wire color) Description
ConditionReference value
(Approx.)
+ – Signal nameInput/
Output
SKIA6649J
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BRAKE FLUIDBR-17
< ON-VEHICLE MAINTENANCE >
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BRAKE FLUID
On Board InspectionINFOID:0000000003772425
LEVEL CHECK
• Make sure the fluid level in reservoir tank is between MAX and MIN lines as shown.
• Visually check around reservoir tank for fluid leaks.
• If fluid level is excessively low, check brake system for leaks.
• If brake warning lamp remains illuminated after parking brake pedal is released, check brake system for fluid leaks.
Drain and RefillINFOID:0000000003772426
CAUTION:
• Refill with new brake fluid. Refer to MA-12, "
Fluids and Lubricants".
• Do not reuse drained brake fluid.
• Do not let brake fluid splash on the painted surfaces of the body. This might damage the paint, so if
splashing it, immediately wipe off the area and wash away with water.
• Before servicing, disconnect ABS actuator and electri c unit (control unit) connector or battery nega-
tive terminal.
1. Connect a vinyl tube to each bleed valve.
2. Depress brake pedal, loosen each bleed valve, and gradually remove brake fluid.
3. Make sure there is no foreign material in reservoir tank, and refill with new brake fluid.
4. Rest foot on brake pedal. Loosen bleed valve. Slowly depress pedal until it stops. Tighten bleed valve. Release brake pedal.
Repeat this process a few times, then pause to add new brake
fluid to master cylinder. Continue until new brake fluid flows out
of the bleed valve.
Bleed the air out of the brake hydraulic system. Refer to BR-17,
"Bleeding Brake System".
Bleeding Brake SystemINFOID:0000000003772427
CAUTION:
While bleeding, pay attention to master cylinder fluid level.
1. Turn ignition switch OFF and disconnect ABS actuator and electric unit (control unit) connector or battery
negative terminal.
2. Connect a vinyl tube to the rear right bleed valve.
LFIA0225E
SBR419C
SBR995
Revision: December 20092009 QX56