2011 INFINITI QX56 USB

AV-66
< ECU DIAGNOSIS INFORMATION >
VIDEO DISTRIBUTOR
29 — Shield — — — —
30 — Shield — — — —
31
(Y/L) Ground Composite image signal
ground for headrest display
unit LH
—Ignition
switch ON —0 V
32
(Y/G) Ground Composite image signal for
headrest display unit LH
OutputIgnition
switch ON When DVD, USB, front
AUX or rear AUX image is
displayed on headrest dis-
play unit LH.
33
(L) Ground
Composite image signal
ground —Ignition
switch
ON —0 V
34
(P) Ground Composite image signal Input Ignition
switch
ON When DVD, USB or front
AUX image is displayed on
headrest display unit LH or
RH.
35 — Shield — — — —
40
(LG) 39
(V) AUX image signal Input Ignition
switch ON When rear AUX image is
displayed on headrest dis-
play unit LH or RH.
41 — Shield — — — —
45
(W) 46
(R) Sound signal LH Input Ignition
switch
ON When DVD, USB or front
AUX mode is selected on
headrest display unit LH or
RH.
47
(B) 48
(G) Sound signal RH Input Ignition
switch ON When DVD, USB or front
AUX mode is selected on
headrest display unit LH or
RH.
49 — Shield — — — —
53 — Shield — — — — Terminal
(Wire color) Description
ConditionReference value
(Approx.)
+ – Signal name Input/
Output
SKIB2251J
SKIB2251J
SKIB2251J
SKIB3609E
SKIB3609E
Revision: 2010 May2011 QX56

AV-136
< DTC/CIRCUIT DIAGNOSIS >
U1225 AV CONTROL UNIT
U1225 AV CONTROL UNIT
DTC LogicINFOID:0000000006216283
DTC DETECTION LOGIC
DTCDisplay contents of CON-
SULT-III DTC detection condition Possible malfunction factor
U1225 USB CONTROLLER
[U1225]
USB connection malfunction is detected. Check that the connection to the USB con-
nector is normal.
Revision: 2010 May2011 QX56

AV-148
< DTC/CIRCUIT DIAGNOSIS >
U1263 USB
U1263 USB
DTC LogicINFOID:0000000006216299
Diagnosis ProcedureINFOID:0000000006216300
1.CHECK USB HARNESS
Visually check USB harness.
Is the inspection result normal?
YES >> Replace AV control unit. Refer to AV-212, "Removal and Installation".
NO >> Replace USB harness.
DTC Display contents of
CONSULT-III DTC detection condition Possible malfunction factor
U1263 USB OVERCURRENT
[U1263] Detection of overcurrent in USB connector. Check USB harness between the AV
control unit and USB connector.
Revision: 2010 May2011 QX56

AV
COMPOSITE IMAGE SIGNAL CIRCUIT (AV CONTROL UNIT TO FRONT DIS-
PLAY UNIT)
AV-167
< DTC/CIRCUIT DIAGNOSIS >
C
DE
F
G H
I
J
K L
M B A
O P
COMPOSITE IMAGE SIGNAL CIRCUI T (AV CONTROL UNIT TO FRONT
DISPLAY UNIT)
DescriptionINFOID:0000000006216328
 DVD is played by inserting DVD into the AV control unit.
 DVD image signals are transmitted to the front display unit and video distributor.
 AV control unit receives the image signal from the front auxiliary input jacks and then transmits it to the front
display unit.
 AV control unit receives the image signal from the USB (video data) and then transmits it to the front display
unit and video distributor.
 Video distributor receives the image signal from the AV control unit and then transmits it to the headrest dis-
play unit.
Diagnosis ProcedureINFOID:0000000006216329
1.CHECK CONTINUITY COMPOS ITE IMAGE SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect AV control unit connector and front display unit connector.
3. Check continuity between AV control unit harness connector and front display unit harness connector.
4. Check continuity between AV control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair harness or connector.
2.CHECK COMPOSITE IMAGE SIGNAL
1. Connect AV control unit connector and front display unit connector.
2. Turn ignition switch ON.
3. Check signal between AV control unit harness connector and ground.
Is the inspection result normal?
YES >> Replace front display unit. Refer to AV-213, "Removal and Installation".
NO >> Replace AV control unit. Refer to AV-212, "
Removal and Installation".
AV control unit Front display unit
Continuity
Connector Terminal Connector Terminal
M210 68 M215 18 Existed
AV control unit GroundContinuity
Connector Terminal
M210 68 Not existed
(+) (− ) Condition Reference value
AV control unit
Connector Terminal
M210 68 Ground At DVD image is displayed.
SKIB2251J
Revision: 2010 May2011 QX56

AV-168
< DTC/CIRCUIT DIAGNOSIS >
COMPOSITE IMAGE SIGNAL CIRCUIT (AV CONTROL UNIT TO VIDEO DISTRIB-
UTOR)
COMPOSITE IMAGE SIGNAL CIRCUI T (AV CONTROL UNIT TO VIDEO
DISTRIBUTOR)
DescriptionINFOID:0000000006216330
 DVD is played by inserting DVD into the AV control unit.
 DVD image signals are transmitted to the front display unit and video distributor.
 AV control unit receives the image signal from the front auxiliary input jacks and then transmits it to the front
display unit.
 AV control unit receives the image signal from the USB (video data) and then transmits it to the front display
unit and video distributor.
 Video distributor receives the image signal from the AV control unit and then transmits it to the headrest dis-
play unit.
Diagnosis ProcedureINFOID:0000000006216331
1.CHECK CONTINUITY COMPOS ITE IMAGE SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect AV control unit connector and video distributor connector.
3. Check continuity between AV control unit har ness connector and video distributor harness connector.
4. Check continuity between video distributor harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair harness or connector.
2.CHECK COMPOSITE IMAGE SIGNAL
1. Connect AV control unit connector and video distributor connector.
2. Turn ignition switch ON.
3. Check signal between video distributor harness connector and ground.
Is the inspection result normal?
YES >> Replace video distributor. Refer to AV-215, "Removal and Installation".
NO >> Replace AV control unit. Refer to AV-212, "
Removal and Installation".
AV control unit Video distributor
Continuity
Connector Terminal Connector Terminal
M209 34 M218 34 Existed
Video distributor GroundContinuity
Connector Terminal
M218 34 Not existed
(+) (− ) Condition Reference value
Video distributor
Connector Terminal
M218 34 Ground When DVD, USB or front AUX im-
age is displayed on headrest dis-
play unit LH or RH.
SKIB2251J
Revision: 2010 May2011 QX56

AV
COMPOSITE IMAGE SIGNAL CIRCUIT (VIDEO DISTRIBUTOR TO HEADREST
DISPLAY UNIT)
AV-169
< DTC/CIRCUIT DIAGNOSIS >
C
DE
F
G H
I
J
K L
M B A
O P
COMPOSITE IMAGE SIGNAL CIRCUIT (VIDEO DISTRIBUTOR TO HEAD-
REST DISPLAY UNIT)
DescriptionINFOID:0000000006216332
 DVD is played by inserting DVD into the AV control unit.
 DVD image signals are transmitted to the front display unit and video distributor.
 AV control unit receives the image signal from the front auxiliary input jacks and then transmits it to the front
display unit.
 AV control unit receives the image signal from the USB (video data) and then transmits it to the front display
unit and video distributor.
 Video distributor receives the image signal from the AV control unit and then transmits it to the headrest dis-
play unit.
Diagnosis ProcedureINFOID:0000000006216333
1.CHECK CONTINUITY COMPOS ITE IMAGE SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect video distributor connecto r and headrest display unit connector.
3. Check continuity between video distributor harne ss connector and headrest display unit harness connec-
tor.
*1: Headrest display unit LH
*2: Headrest display unit RH
4. Check continuity between headrest display unit harness connector and ground.
*1: Headrest display unit LH
*2: Headrest display unit RH
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair harness or connector.
2.CHECK COMPOSITE IMAGE SIGNAL
1. Connect video distributor connector and rear display unit connector.
2. Turn ignition switch ON.
3. Check signal between rear display unit harness connector using an oscilloscope.
Video distributor Headrest display unit Continuity
Connector Terminal Connector Terminal
M217 32
B554
*124 Existed
28 B574
*224 Existed
Headrest display unit GroundContinuity
Connector Terminal
B554
*124 Not existed
B574
*224
(+)
(− ) Condition Reference value
Headrest display unit
Connector Terminal
Revision: 2010 May2011 QX56

AV-170
< DTC/CIRCUIT DIAGNOSIS >
COMPOSITE IMAGE SIGNAL CIRCUIT (VIDEO DISTRIBUTOR TO HEADREST
DISPLAY UNIT)
*1: Headrest display unit LH
*2: Headrest display unit RH
Is the inspection result normal?
YES >> Replace headrest display unit. Refer to AV-214, "Exploded View".
NO >> Replace video distributor. Refer to AV-215, "
Removal and Installation".
B554*124
GroundWhen DVD, USB or front AUX im-
age is displayed on headrest dis-
play unit LH or RH.
B574
*224
SKIB2251J
Revision: 2010 May2011 QX56

AV-174
< DTC/CIRCUIT DIAGNOSIS >
IMAGE SWITCH SIGNAL CIRCUIT
Is the inspection result normal?
YES >> Replace video distributor. Refer to AV-215, "Removal and Installation".
NO >> Replace headrest display unit LH (RH). Refer to AV-214, "
Exploded View".
M2179
Ground When DVD, USB or front AUX
image is displayed on headrest
display unit RH.
0.5 V
When rear AUX image is dis-
played on headrest display unit
RH. 4.5 V
10 When DVD, USB or front AUX
image is displayed on headrest
display unit LH.
0.5 V
When rear AUX image is dis-
played on headrest display unit
LH. 4.5 V
Revision: 2010 May2011 QX56