Page 395 of 4083
![INFINITI QX56 2008 Factory Service Manual BCS-30
< COMPONENT DIAGNOSIS >[BCM]
U1000 CAN COMM CIRCUIT
COMPONENT DIAGNOSIS
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000001696433
Refer to
LAN-44, "CAN Communication Signal Chart".
DTC LogicIN INFINITI QX56 2008 Factory Service Manual BCS-30
< COMPONENT DIAGNOSIS >[BCM]
U1000 CAN COMM CIRCUIT
COMPONENT DIAGNOSIS
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000001696433
Refer to
LAN-44, "CAN Communication Signal Chart".
DTC LogicIN](/manual-img/42/57030/w960_57030-394.png)
BCS-30
< COMPONENT DIAGNOSIS >[BCM]
U1000 CAN COMM CIRCUIT
COMPONENT DIAGNOSIS
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000001696433
Refer to
LAN-44, "CAN Communication Signal Chart".
DTC LogicINFOID:0000000001696434
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000001696435
1. PERFORM SELF DIAGNOSTIC
1. Turn ignition switch ON and wait for 2 seconds or more.
2. Check “Self Diagnostic Result” of BCM.
Is
“CAN COMM CIRCUIT” displayed?
YES >> Refer to LAN-14, "Trouble Diagnosis Flow Chart".
NO >> Refer to GI-38, "
Intermittent Incident".
DTCCONSULT-III display
description DTC Detection Condition
Possible cause
U1000 CAN COMM CIRCUIT When BCM cannot communicate CAN com-
munication signal continuously for 2 sec-
onds or more. Any item (or items) of the following listed below is
malfunctioning in CAN communication system.
•Transmission
• Receiving (ECM)
• Receiving (METER/M&A)
• Receiving (TCM)
• Receiving (MULTI AV)
• Receiving (IPDM E/R)
• Receiving (I-KEY)
Revision: March 2010
2008 QX56
Page 397 of 4083
![INFINITI QX56 2008 Factory Service Manual BCS-32
< COMPONENT DIAGNOSIS >[BCM]
POWER SUPPLY AND GROUND CIRCUIT
POWER SUPPLY AND GROUND CIRCUIT
Diagnosis ProcedureINFOID:0000000001696439
1. CHECK FUSES AND FUSIBLE LINK
Check that the following INFINITI QX56 2008 Factory Service Manual BCS-32
< COMPONENT DIAGNOSIS >[BCM]
POWER SUPPLY AND GROUND CIRCUIT
POWER SUPPLY AND GROUND CIRCUIT
Diagnosis ProcedureINFOID:0000000001696439
1. CHECK FUSES AND FUSIBLE LINK
Check that the following](/manual-img/42/57030/w960_57030-396.png)
BCS-32
< COMPONENT DIAGNOSIS >[BCM]
POWER SUPPLY AND GROUND CIRCUIT
POWER SUPPLY AND GROUND CIRCUIT
Diagnosis ProcedureINFOID:0000000001696439
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.
Terminal No. Signal nameFuses 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)
ConnectorTe 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: March 2010 2008 QX56
Page 398 of 4083
![INFINITI QX56 2008 Factory Service Manual BCS
COMBINATION SWITCH INPUT CIRCUITBCS-33
< COMPONENT DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
COMBINATION SWITCH
INPUT CIRCUIT
Diagnosis ProcedureINFOID:0000000001696440
1. CHECK INPUT 1 - 5 INFINITI QX56 2008 Factory Service Manual BCS
COMBINATION SWITCH INPUT CIRCUITBCS-33
< COMPONENT DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
COMBINATION SWITCH
INPUT CIRCUIT
Diagnosis ProcedureINFOID:0000000001696440
1. CHECK INPUT 1 - 5](/manual-img/42/57030/w960_57030-397.png)
BCS
COMBINATION SWITCH INPUT CIRCUITBCS-33
< COMPONENT DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
COMBINATION SWITCH
INPUT CIRCUIT
Diagnosis ProcedureINFOID:0000000001696440
1. CHECK INPUT 1 - 5 SYSTEM CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect BCM and combination switch.
3. Check continuity between BCM harness connector and combi- nation switch harness connector.
Does continuity exist?
YES >> GO TO 2
NO >> Repair or replace harness.
2. CHECK INPUT 1 - 5 SYSTEM CIRCUIT FOR SHORT
Check for continuity between BCM harness connector and ground.
Does continuity exist?
YES >> Repair or replace harness.
NO >> GO TO 3
3. CHECK BCM OUTPUT VOLTAGE
1. Connect BCM.
2. Turn ignition switch ON.
3. Check voltage between BCM harness connector and ground.
Is the measurement value normal?
System BCM
Combination switch
Continuity
Connector Terminal Connector Terminal
INPUT 1
M18(A) 6
M28(B) 6
Ye s
INPUT 2
57
INPUT 3 410
INPUT 4 39
INPUT 5 28
ALMIA0275ZZ
SystemBCM
GroundContinuity
Connector Terminal
INPUT 1
M186
No
INPUT 2
5
INPUT 3 4
INPUT 4 3
INPUT 5 2
ALMIA0276ZZ
SystemTe r m i n a l s
Voltag e
(Approx.)
(+)
(− )
BCM
Ground
Connector Terminal
INPUT 1
M186
Refer to BCS-
38, "Refer-
ence Value".
INPUT 2
5
INPUT 3 4
INPUT 4 3
INPUT 5 2
ALMIA0277ZZ
Revision: March 2010 2008 QX56
Page 400 of 4083
![INFINITI QX56 2008 Factory Service Manual BCS
COMBINATION SWITCH OUTPUT CIRCUITBCS-35
< COMPONENT DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
COMBINATION SWITCH
OUTPUT CIRCUIT
Diagnosis ProcedureINFOID:0000000001696442
1. CHECK OUTPUT 1 INFINITI QX56 2008 Factory Service Manual BCS
COMBINATION SWITCH OUTPUT CIRCUITBCS-35
< COMPONENT DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
COMBINATION SWITCH
OUTPUT CIRCUIT
Diagnosis ProcedureINFOID:0000000001696442
1. CHECK OUTPUT 1](/manual-img/42/57030/w960_57030-399.png)
BCS
COMBINATION SWITCH OUTPUT CIRCUITBCS-35
< COMPONENT DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
COMBINATION SWITCH
OUTPUT CIRCUIT
Diagnosis ProcedureINFOID:0000000001696442
1. CHECK OUTPUT 1 - 5 SYSTEM CIRCUIT FOR OPEN
1. Turn ignition switch OFF.
2. Disconnect BCM and combination switch.
3. Check continuity between BCM harness connector and combi- nation switch harness connector.
Does continuity exist?
YES >> GO TO 2
NO >> Repair or replace harness.
2. CHECK OUTPUT 1 - 5 SYSTEM CIRCUIT FOR SHORT
Check for continuity between BCM harness connector and ground.
Does continuity exist?
YES >> Repair or replace harness.
NO >> GO TO 3
3. CHECK COMBINATION SWITCH
Check combination switch. Refer to BCS-36, "
Description".
Is the check result normal?
YES >> Replace BCM. Refer to BCS-55, "Removal and Installation".
NO >> Replace combination switch (applicable parts). Refer to EXL-119, "
Removal and Installation".
Special Repair RequirementINFOID:0000000001696443
1. ADDITIONAL SERVICE WHEN REPLACING BCM
>> Refer to BCS-3, "
ADDITIONAL SERVICE WHEN REPLAC ING CONTROL UNIT : Special Repair
Requirement".
SystemBCM
Combination switch
Continuity
Connector Terminal Connector Terminal
OUTPUT 1
M18(A) 36
M28(B) 1
Ye s
OUTPUT 2
352
OUTPUT 3 343
OUTPUT 4 334
OUTPUT 5 325
ALMIA0278ZZ
SystemBCM
GroundContinuity
Connector Terminal
OUTPUT 1
M1836
No
OUTPUT 2
35
OUTPUT 3 34
OUTPUT 4 33
OUTPUT 5 32
ALMIA0279ZZ
Revision: March 2010 2008 QX56
Page 404 of 4083
![INFINITI QX56 2008 Factory Service Manual BCS
BCM (BODY CONTROL MODULE)BCS-39
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
HEADLAMP SW1
Headlamp switch OFF OFF
Headlamp switch 1st
ON
HEADLAMP SW2 Headlamp switch OFF
OFF
Headlamp swit INFINITI QX56 2008 Factory Service Manual BCS
BCM (BODY CONTROL MODULE)BCS-39
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
HEADLAMP SW1
Headlamp switch OFF OFF
Headlamp switch 1st
ON
HEADLAMP SW2 Headlamp switch OFF
OFF
Headlamp swit](/manual-img/42/57030/w960_57030-403.png)
BCS
BCM (BODY CONTROL MODULE)BCS-39
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
HEADLAMP SW1
Headlamp switch OFF OFF
Headlamp switch 1st
ON
HEADLAMP SW2 Headlamp switch OFF
OFF
Headlamp switch 1st ON
HI BEAM SW High beam switch OFF
OFF
High beam switch HI ON
IGN ON SW Ignition switch OFF or ACC
OFF
Ignition switch ON ON
IGN SW CAN Ignition switch OFF or ACC
OFF
Ignition switch ON ON
INT VOLUME Wiper intermittent dial is in a dial position 1 - 7 1 - 7
I-KEY LOCK LOCK button of Intelligent Key is not pressed
OFF
LOCK button of Intelligent Key is pressed ON
I-KEY UNLOCK UNLOCK button of Intelligent Key is not pressed
OFF
UNLOCK button of Intelligent Key is pressed ON
KEY ON SW Mechanical key is removed from key cylinder
OFF
Mechanical key is inserted to key cylinder ON
OIL PRESS SW • Ignition switch OFF or ACC
• Engine running
OFF
Ignition switch ON ON
PASSING SW Other than lighting switch PASS
OFF
Lighting switch PASS ON
REAR DEF SW Rear window defogger switch OFF
OFF
Rear window defogger switch ON ON
RR WASHER SW Rear washer switch OFF
OFF
Rear washer switch ON ON
RR WIPER INT Rear wiper switch OFF
OFF
Rear wiper switch INT ON
RR WIPER ON Rear wiper switch OFF
OFF
Rear wiper switch ON ON
RR WIPER STOP Rear wiper stop position
OFF
Other than rear wiper stop position ON
TAIL LAMP SW Lighting switch OFF
OFF
Lighting switch 1ST ON
TRNK OPNR SW When back door opener switch is not pressed
OFF
When back door opener switch is pressed ON
TURN SIGNAL L Turn signal switch OFF
OFF
Turn signal switch LH ON
TURN SIGNAL R Turn signal switch OFF
OFF
Turn signal switch RH ON
VEHICLE SPEED While driving Equivalent to speedo meter reading
Monitor Item
Condition Value/Status
Revision: March 2010 2008 QX56
Page 406 of 4083
![INFINITI QX56 2008 Factory Service Manual BCS
BCM (BODY CONTROL MODULE)BCS-41
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
( INFINITI QX56 2008 Factory Service Manual BCS
BCM (BODY CONTROL MODULE)BCS-41
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(](/manual-img/42/57030/w960_57030-405.png)
BCS
BCM (BODY CONTROL MODULE)BCS-41
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(Approx.)
Ignition
switch Operation or condition
1BR/W Ignition keyhole illumi-
nation Output OFFDoor is locked (SW OFF)
Battery voltage
Door is unlocked (SW ON) 0V
2SB Combination switch
input 5 Input ON
Lighting, turn, wiper OFF
Wiper dial position 4
3G/Y Combination switch
input 4 Input ONLighting, turn, wiper OFF
Wiper dial position 4
4Y Combination switch
input 3 Input ON
Lighting, turn, wiper OFF
Wiper dial position 4
5G/B Combination switch
input 2
Input ONLighting, turn, wiper OFF
Wiper dial position 4
6V Combination switch
input 1
9GR/R Rear window defogger
switch
Input ONRear window defogger switch
ON
0V
Rear window defogger switch
OFF 5V
10 G Hazard lamp flash Input OFF ON (opening or closing)
0V
OFF (other than above) Battery voltage
11 O Ignition switch (ACC
or ON)
InputACC or
ON Ignition switch ACC or ON
Battery voltage
12 R/L Front door switch RH Input OFF ON (open)
0V
OFF (closed) Battery voltage
13 GR Rear door switch RH Input OFF ON (open)
0V
OFF (closed) Battery voltage
15 L/W Tire pressure warning
check connector
Input OFF
—5V
18 P Remote keyless entry
receiver and optical
sensor (ground)
Output OFF
—0V
SKIA5291E
SKIA5292E
SKIA5291E
SKIA5292E
Revision: March 2010 2008 QX56
Page 407 of 4083
![INFINITI QX56 2008 Factory Service Manual BCS-42
< ECU DIAGNOSIS >[BCM]
BCM (BODY CONTROL MODULE)
19 V/WRemote keyless entry
receiver (power sup-
ply) Output OFF Ignition switch OFF
20 G/W Remote keyless entry
receiver (signal) Input OFFSta INFINITI QX56 2008 Factory Service Manual BCS-42
< ECU DIAGNOSIS >[BCM]
BCM (BODY CONTROL MODULE)
19 V/WRemote keyless entry
receiver (power sup-
ply) Output OFF Ignition switch OFF
20 G/W Remote keyless entry
receiver (signal) Input OFFSta](/manual-img/42/57030/w960_57030-406.png)
BCS-42
< ECU DIAGNOSIS >[BCM]
BCM (BODY CONTROL MODULE)
19 V/WRemote keyless entry
receiver (power sup-
ply) Output OFF Ignition switch OFF
20 G/W Remote keyless entry
receiver (signal) Input OFFStand-by (keyfob buttons re-
leased)
When remote keyless entry
receiver receives signal from
keyfob (keyfob buttons
pressed)
21 G NATS antenna amp. Input OFF
→
ON Ignition switch (OFF
→ ON)Just after turning ignition switch
ON: Pointer of tester should
move for approx. 1 second, then return to battery voltage.
22 W/V BUS — —Ignition switch ON or power
window timer operates
23 G/O Security indicator
lamp Output OFF
Goes OFF
→ illuminates (Ev-
ery 2.4 seconds) Battery voltage
→ 0V
25 BR NATS antenna amp. Input OFF
→
ON Ignition switch (OFF
→ ON)Just after turning ignition switch
ON: Pointer of tester should
move for approx. 1 second, then return to battery voltage.
26 Y/L Rear wiper auto stop
switch 2 Input ONRise up position (rear wiper
arm on stopper)
0V
A Position (full clockwise stop
position) 0V
Forward sweep (counterclock-
wise direction) Fluctuating
B Position (full counterclock-
wise stop position) Battery voltage
Reverse sweep (clockwise di-
rection) Fluctuating
27 W/R Compressor ON sig-
nal Input ONA/C switch OFF
5V
A/C switch ON 0V
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(Approx.)
Ignition
switch Operation or condition
LIIA1893E
LIIA1894E
LIIA1895E
PIIA2344E
Revision: March 2010
2008 QX56
Page 408 of 4083
![INFINITI QX56 2008 Factory Service Manual BCS
BCM (BODY CONTROL MODULE)BCS-43
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
28 L/R Front blower monitor Input ON
Front blower motor OFF Battery voltage
Front blower motor ON
0V
29 W/B Ha INFINITI QX56 2008 Factory Service Manual BCS
BCM (BODY CONTROL MODULE)BCS-43
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
28 L/R Front blower monitor Input ON
Front blower motor OFF Battery voltage
Front blower motor ON
0V
29 W/B Ha](/manual-img/42/57030/w960_57030-407.png)
BCS
BCM (BODY CONTROL MODULE)BCS-43
< ECU DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
28 L/R Front blower monitor Input ON
Front blower motor OFF Battery voltage
Front blower motor ON
0V
29 W/B Hazard switch Input OFFON
0V
OFF 5V
30 Y/BR Glass hatch switch Input OFF Glass hatch switch released
Battery voltage
Glass hatch switch pressed 0
32 R/G Combination switch
output 5
Output ONLighting, turn, wiper OFF
Wiper dial position 4
33 R/Y Combination switch
output 4 Output ONLighting, turn, wiper OFF
Wiper dial position 4
34 L Combination switch
output 3 Output ON
Lighting, turn, wiper OFF
Wiper dial position 4
35 O/B Combination switch
output 2
Output ONLighting, turn, wiper OFF
Wiper dial position 4
36 R/W Combination switch
output 1
37 B/R Key switch and igni-
tion knob switch Input OFFIntelligent Key inserted
Battery voltage
Intelligent Key inserted 0V
38 W/L Ignition switch (ON) Input ON —Battery voltage
39 L CAN-H — —— —
40 P CAN-L — —— —
42 GR Glass hatch ajar
switch Input ONGlass hatch open
0
Glass hatch closed Battery
43 R/B Back door latch (door
ajar switch) Input OFFON (open)
0V
OFF (closed) Battery voltage
Te r m i n a l
Wire
color Signal name Signal
input/
output Measuring condition
Reference value or waveform
(Approx.)
Ignition
switch Operation or condition
SKIA5291E
SKIA5292E
SKIA5291E
SKIA5292E
Revision: March 2010
2008 QX56