ignition INFINITI QX56 2009 Factory Owner's Guide

ADP-44
< COMPONENT DIAGNOSIS >
B2128 UART COMMUNICATION LINE
B2128 UART COMMUNICATION LINE
DescriptionINFOID:0000000003775544
Driver seat control unit performs UART communication with the automatic drive positioner control unit using 2
communication lines, TX and RX line. Driver seat cont rol unit receives the operation signals of pedal adjusting
switch, door mirror remote control switch, set switch and memory switch and the position signals of adjustable
pedal sensor and door mirror sensor from the automatic drive positioner control unit and transmits the opera-
tion request signal.
DTC LogicINFOID:0000000003775545
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1. STEP 1
Turn ignition switch ON.
>> GO TO 2
2. STEP 2
Operate pedal adjusting switch for more than 2 seconds.
>> GO TO 3
3. PROCEDURE 3
Check “Self diagnostic result” with CONSULT-III.
Is the DTC detected?
YES >> Perform diagnosis procedure. Refer to ADP-44, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000003775546
1. CHECK UART COMMUNICA TION LINE CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect driver seat contro l unit and automatic drive posi-
tioner control unit.
3. Check continuity between driver seat control unit harness con- nector and automatic drive positi oner control unit harness con-
nector.
4. Check continuity between driver seat control unit harness connector and ground.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause B2128 UART COMM The communication between driver seat control unit
and automatic drive positioner control unit is interrupt-
ed for a period of time.  UART communication line
(UART communication line is
open or shorted)
 Driver seat control unit
 Automatic drive positioner control unit
Driver seat control unit connector Te r m i n a lAutomatic drive positioner
control unit connector Terminal Continuity
B202 1
M33 10
Ye s
17 26
PIIA4598E
Revision: December 20092009 QX56

ADP-46
< COMPONENT DIAGNOSIS >
POWER SUPPLY AND GROUND CIRCUIT
POWER SUPPLY AND GROUND CIRCUIT
BCM
BCM : Diagnosis ProcedureINFOID:0000000004055989
1. CHECK FUSES AND FUSIBLE LINK
Check that the following fuses and fusible link are not blown.
Is the fuse blown?
YES >> Replace the blown fuse or fusible link after repairing the affected circuit.
NO >> GO TO 2
2. CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect BCM.
3. Check voltage between BCM harness connector and ground.
Is the measurement value normal?
YES >> GO TO 3
NO >> Repair or replace harness.
3. CHECK GROUND CIRCUIT
Check continuity between BCM harness connector and ground.
Does continuity exist?
YES >> Inspection End.
NO >> Repair or replace harness.
DRIVER SEAT CONTROL UNIT
Terminal No. Signal name Fuses and fusible link No.
57 Battery power supply 22 (15A)
70 F (50A)
11 Ignition ACC or ON 4 (10A)
38 Ignition ON or START 59 (10A)
Connector Te r m i n a l s
Power
source Condition
Voltage (V) (Ap-
prox.)
(+) (-)
M18 11 Ground
ACC
power
supply Ignition
switch
ACC or ON Battery voltage
38 Ground Ignition
power
supply Ignition
switch ON or START Battery voltage
M20 57 Ground
Battery
power
supply Ignition
switch
OFF Battery voltage
70 Ground Battery
power
supply Ignition
switch OFF Battery voltage
LIIA2415E
BCM
GroundContinuity
Connector Terminal
M20 67 Yes
LIIA0915E
Revision: December 20092009 QX56

POWER SUPPLY AND GROUND CIRCUITADP-47
< COMPONENT DIAGNOSIS >
C
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F
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M A
B
ADP
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DRIVER SEAT CONTROL UNIT : Diagnosis ProcedureINFOID:0000000003775549
NOTE:
Do not disconnect the battery negative terminal and the dr iver seat control unit connector until DTC is con-
firmed with CONSULT-III.
1. CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconeect driver seat control unit.
3. Check voltage between driver s eat control unit harness connec-
tor and ground.
Is the inspection result normal?
YES >> GO TO 2
NO >> Check the following.  Repair or replace harness between driver seat control unit and fuse block (J/B).
 Circuit breaker.
2. CHECK GROUND CIRCUIT
Check continuity between the driv er seat control unit harness con-
nector and ground.
Is the inspection result normal?
YES >> Driver seat control unit power supply and ground circuit are OK.
NO >> Repair or replace harness.
DRIVER SEAT CONTROL UNIT : Special Repair RequirementINFOID:0000000003775550
1. PERFORM ADDITIONAL SERVICE
Perform additional service when removing battery negative terminal.
>> Refer to Owner’s Manual.
AUTOMATIC DRIVE POSITIONER CONTROL UNIT
AUTOMATIC DRIVE POSITIONER CO NTROL UNIT : Diagnosis Procedure
INFOID:0000000003775551
NOTE:
Do not disconnect the battery negative terminal and the dr iver seat control unit connector until DTC is con-
firmed with CONSULT-III.
Te r m i n a l s
Power
source ConditionVoltage (V)
(Approx.)
(+)
(–)
Driver seat
control unit connector Terminal
B202 6 GroundSTART
power sup-
ply Ignition
switch
START Battery
voltage
B203 33 Battery
power sup-ply Ignition
switch OFF
40
LIIA1897E
Driver seat control unit
connector Te r m i n a l
Ground Continuity
B202 32 Ye s
B203 48
PIIA4542E
Revision: December 20092009 QX56

ADP-48
< COMPONENT DIAGNOSIS >
POWER SUPPLY AND GROUND CIRCUIT
1. CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect automatic drive positioner control unit.
3. Check voltage between automatic drive positioner control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair or replace harness.
2. CHECK GROUND CIRCUIT
Check continuity between the automat ic drive positioner control unit
harness connector and ground.
Is the inspection result normal?
YES >> Automatic drive positioner control unit power supply and ground circuit are OK.
NO >> Repair or replace harness.
AUTOMATIC DRIVE POSITIONER CONTROL UNIT : Special Repair Requirement
INFOID:0000000003775552
1. PERFORM ADDITIONAL SERVICE
Perform additional service when removing battery negative terminal.
>> Refer to Owner’s Manual.
Te r m i n a l s Voltage (V)(Approx.)
(+)
(–)
Automatic drive positioner
control unit connector Te r m i n a l
M34 34
Ground Battery voltage
39
PIIA4543E
Automatic drive positioner
control unit connector Te r m i n a l
GroundContinuity
M34 40
Ye s
48
PIIA4544E
Revision: December 20092009 QX56

SLIDING SWITCHADP-49
< COMPONENT DIAGNOSIS >
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ADP
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SLIDING SWITCH
DescriptionINFOID:0000000003775553
Sliding switch is equipped to the power seat switch LH on the seat cushion trim cover. The operation signal is
input to the driver seat control unit when the sliding switch is operated.
Component Function CheckINFOID:0000000003775554
1. CHECK FUNCTION
1. Select “SLIDE SW-FR”, “SLIDE SW-RR” in “Data monitor” mode with CONSULT-III.
2. Check sliding switch signal under the following conditions.
Is the indication normal?
YES >> Inspection End.
NO >> Perform diagnosis procedure. Refer to ADP-49, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003775555
1. CHECK SLIDING SWITCH SIGNAL
1. Turn ignition switch OFF.
2. Check voltage between driver s eat control unit harness connec-
tor and ground.
Is the inspection result normal?
YES >> GO TO 5
NO >> GO TO 2
2. CHECK SLIDING SWITCH CIRCUIT
1. Disconnect driver seat control unit and power seat switch LH.
2. Check continuity between driver seat control unit harness con-
nector and power seat switch LH harness connector.
3. Check continuity between driver seat control unit harness con-
nector and ground.
Monitor item Condition Status
SLIDE SW-FR Sliding switch (forward) Operate ON
Release OFF
SLIDE SW-RR Sliding switch (backward) Operate ON
Release OFF
Driver seat control
unit connector Te r m i n a l s
ConditionVoltage (V)
(Approx.)
(+) (–)
B202 11
Ground Sliding
switch Operate
(backward) 0
Release Battery
voltage
26 Operate
(forward) 0
Release Battery
voltage
PIIA4577E
Driver seat control
unit connector Te r m i n a l
Power seat switch
LH connector Terminal Continuity
B202 (A) 11
B208 (B) 1
Ye s
26 5
ALJIA0308ZZ
Revision: December 20092009 QX56

ADP-50
< COMPONENT DIAGNOSIS >
SLIDING SWITCH
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness.
3. CHECK DRIVER SEAT CONTROL UNIT OUTPUT
1. Connect the driver seat control unit.
2. Turn ignition switch ON.
3. Check voltage between driver seat control unit harness connec- tor and ground.
Is the inspection result normal?
YES >> GO TO 4
NO >> Replace driver seat control unit. Refer to ADP-165, "Removal and Installation"
.
4. CHECK SLIDING SWITCH
Refer to ADP-50, "Component Inspection"
.
Is the inspection result normal?
YES >> GO TO 5
NO >> Replace power seat switch LH. Refer to SE-68, "Disassembly and Assembly"
.
5. CHECK INTERMITTENT INCIDENT
Refer to GI-38, "Intermittent Incident"
.
Is the inspection result normal?
YES >> Replace driver seat control unit. Refer to ADP-165, "Removal and Installation".
NO >> Repair or replace malfunctioning part.
Component InspectionINFOID:0000000003775556
1. CHECK SLIDING SWITCH
1. Turn ignition switch OFF.
2. Disconnect power seat switch LH.
3. Check continuity between power seat switch LH terminals.
Is the inspection result normal?
YES >> Inspection End.
NO >> Replace power seat switch LH. Refer to SE-68, "Disassembly and Assembly"
.
Driver seat control unit
connector Terminal
GroundContinuity
B202 (A) 11
No
26
Driver seat control unit
connector Te r m i n a l s
Voltage (V)
(Approx.)
(+) (–)
B202 11
Ground Battery voltage
26
PIIA4577E
Te r m i n a l Condition Continuity
Power seat switch LH
7 1 Sliding switch (backward)
Operate Yes
Release No
5 Sliding switch (forward) Operate Yes
Release No
ALJIA0309ZZ
Revision: December 20092009 QX56

RECLINING SWITCHADP-51
< COMPONENT DIAGNOSIS >
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ADP
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RECLINING SWITCH
DescriptionINFOID:0000000003775557
Reclining switch is equipped to the power seat switch LH on the seat cushion trim cover. The operation signal
is input to the driver seat control unit when the reclining switch is operated.
Component Function CheckINFOID:0000000003775558
1. CHECK FUNCTION
1. Select “RECLN SW-FR”, “RECLN SW-RR” in “Data monitor” mode with CONSULT-III.
2. Check reclining switch signal under the following conditions.
Is the indication normal?
YES >> Inspection End.
NO >> Perform diagnosis procedure. Refer to ADP-51, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003775559
1. CHECK RECLINING SWITCH SIGNAL
1. Turn ignition switch OFF.
2. Check voltage between driver s eat control unit harness connec-
tor and ground.
Is the inspection result normal?
YES >> GO TO 5
NO >> GO TO 2
2. CHECK RECLINING SWITCH CIRCUIT
1. Disconnect driver seat control unit and power seat switch LH.
2. Check continuity between driver seat control unit harness con-
nector and power seat switch LH harness connector.
3. Check continuity between driver seat control unit harness con-
nector and ground.
Monitor item Condition Status
RECLN SW-FR Reclining switch (forward) Operate ON
Release OFF
RECLN SW-RR Reclining switch (backward) Operate ON
Release OFF
Driver seat
control unit
connector Te r m i n a l s
ConditionVoltage (V)
(Approx.)
(+) (–)
B202 12
Ground Reclining
switch Operate
(backward) 0
Release Battery voltage
27 Operate
(forward) 0
Release Battery voltage
PIIA4580E
Driver seat control unit connector Te r m i n a l
Power seat switch
LH connector Terminal Continuity
B202 (A) 12
B208 (B) 9
Ye s
27 10
ALJIA0310ZZ
Revision: December 20092009 QX56

ADP-52
< COMPONENT DIAGNOSIS >
RECLINING SWITCH
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness.
3. CHECK DRIVER SEAT CONTROL UNIT OUTPUT
1. Connect the driver seat control unit.
2. Turn ignition switch OFF.
3. Check voltage between driver seat control unit harness connec- tor and ground.
Is the inspection result normal?
YES >> GO TO 4
NO >> Replace driver seat control unit. Refer to ADP-165, "Removal and Installation"
.
4. CHECK RECLINING SWITCH
Refer to ADP-52, "Component Inspection"
.
Is the inspection result normal?
YES >> GO TO 5
NO >> Replace power seat switch LH. Refer to SE-68, "Disassembly and Assembly"
.
5. CHECK INTERMITTENT INCIDENT
Refer to GI-38, "Intermittent Incident"
.
Is the inspection result normal?
YES >> Replace driver seat control unit. Refer to ADP-165, "Removal and Installation".
NO >> Repair or replace the malfunctioning part.
Component InspectionINFOID:0000000003775560
1. CHECK RECLINING SWITCH
1. Turn ignition switch OFF.
2. Disconnect power seat switch LH.
3. Check continuity between power seat switch LH terminals.
Is the inspection result normal?
YES >> Inspection End.
NO >> Replace power seat switch LH. Refer to SE-68, "Disassembly and Assembly"
.
Driver seat control unit
connector Terminal
GroundContinuity
B202 (A) 12
No
27
Driver seat control
unit connector Te r m i n a l s
Voltage (V)
(Approx.)
(+) (–)
B202 12
Ground Battery voltage
27
PIIA4580E
Te r m i n a l s Condition Continuity
Power seat switch LH
7 3
Reclining switch
(backward) Operate Yes
Release No
4 Reclining switch
(forward) Operate Yes
Release No
ALJIA0311ZZ
Revision: December 20092009 QX56

LIFTING SWITCH (FRONT)ADP-53
< COMPONENT DIAGNOSIS >
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ADP
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LIFTING SWITCH (FRONT)
DescriptionINFOID:0000000003775561
Lifting switch (front) is equipped to the power seat swit ch LH on the seat cushion trim cover. The operation sig-
nal is input to the driver seat control unit when the lifting switch (front) is operated.
Component Function CheckINFOID:0000000003775562
1. CHECK FUNCTION
1. Select “LIFT FR SW-UP”, “LIFT FR SW-DN” in “DATA MONITOR” mode with CONSULT-III.
2. Check lifting switch (front) signal under the following conditions.
Is the indication normal?
YES >> Inspection End.
NO >> Perform diagnosis procedure. Refer to ADP-53, "Diagnosis Procedure"
.
Diagnosis ProcedureINFOID:0000000003775563
1. CHECK LIFTING SWITCH SIGNAL
1. Turn ignition switch OFF.
2. Check voltage between driver s eat control unit harness connec-
tor and ground.
Is the inspection result normal?
YES >> GO TO 5
NO >> GO TO 2
2. CHECK LIFTING SWITCH (FRONT) CIRCUIT
1. Disconnect driver seat control unit and power seat switch LH.
2. Check continuity between driver seat control unit harness con-
nector and power seat switch LH harness connector.
3. Check continuity between driver seat control unit harness con-
nector and ground.
Monitor item Condition Status
LIFT FR SW-UP Lifting switch front (up) Operate ON
Release OFF
LIFT FR SW-DN Lifting switch front (down) Operate ON
Release OFF
Driver seat
control unit
connector Te r m i n a l s
ConditionVoltage (V)
(Approx.)
(+) (–)
B202 13
Ground Lifting
switch (front) Operate
(down) 0V
Release Battery
voltage
28 Operate (up) 0V
Release Battery
voltage
PIIA4583E
Driver seat control unit connector Te r m i n a lPower seat switch
LH connector Terminal Continuity
B202 (A) 13
B208 (B) 9
Ye s
28 10
ALJIA0312ZZ
Revision: December 20092009 QX56

ADP-54
< COMPONENT DIAGNOSIS >
LIFTING SWITCH (FRONT)
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness.
3. CHECK DRIVER SEAT CONTROL UNIT OUTPUT
1. Connect the driver seat control unit.
2. Turn ignition switch OFF.
3. Check voltage between driver seat control unit harness connec- tor and ground.
Is the inspection result normal?
YES >> GO TO 4
NO >> Replace driver seat control unit. Refer to ADP-165, "Removal and Installation"
.
4. CHECK LIFTING SWITCH (FRONT)
Refer to ADP-54, "Component Inspection"
.
Is the inspection result normal?
YES >> GO TO 5
NO >> Replace power seat switch LH. Refer to SE-68, "Disassembly and Assembly"
.
5. CHECK INTERMITTENT INCIDENT
Refer to GI-38, "Intermittent Incident"
.
Is the inspection result normal?
YES >> Replace driver seat control unit. Refer to ADP-165, "Removal and Installation".
NO >> Repair or replace the malfunctioning part.
Component InspectionINFOID:0000000003775564
1. CHECK LIFTING SWITCH (FRONT)
1. Turn ignition switch OFF.
2. Disconnect power seat switch LH.
3. Check continuity between power seat switch LH terminals.
Is the inspection result normal?
YES >> Inspection End.
NO >> Replace power seat switch LH. Refer to SE-68, "Disassembly and Assembly"
.
Driver seat control unit
connector Te r m i n a l
GroundContinuity
B202 (A) 13
No
28
Driver seat control unit
connector Te r m i n a l s
Voltage (V)
(Approx.)
(+) (–)
B202 13
Ground Battery voltage
28
PIIA4583E
Te r m i n a l Condition Continuity
Power seat switch LH
7 9 Lifting switch front (down)
Operate Yes
Release No
10 Lifting switch front (up) Operate Yes
Release No
ALJIA0313ZZ
Revision: December 20092009 QX56