INFINITI QX56 2009 Factory Service Manual
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BCS
DIAGNOSIS SYSTEM (BCM)BCS-27
< FUNCTION DIAGNOSIS > [BCM]
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AIR PRESSURE MONITOR
AIR PRESSURE MONITOR : Diagnosis DescriptionINFOID:0000000003776404
DESCRIPTION
During driving, the TPMS receives the signal transmitt
ed from the transmitter installed in each wheel, when
the tire pressure becomes low. The control unit (BC M) of this system has pressure judgment and trouble diag-
nosis functions.
When the TPMS detects low inflation pressure or anot her unusual symptom, the warning lamps in the combi-
nation meter comes on.
SELF DIAGNOSTIC PROCE DURE (WITH CONSULT-III)
With CONSULT-III
Touch “SELF-DIAG RESULTS” display to show malf unction experienced since the last erasing operation.
Refer to BCS-51, "DTC Index"
.
SELF DIAGNOSTIC PROCE DURE (WITHOUT CONSULT-III)
Without CONSULT-III
To start the self-diagnostic results mode, ground terminal of the tire pressure warning check connector. The
malfunction location is indicated by the warning lamp flashing.
NOTE:
When the low tire warning lamp flashes 5 Hz and continues repeating it, the system is normal.
Test Item Operation Description
OIL PRESSURE SW OFF OFF
ON
BCM transmits the oil pressure switch signal to the combination meter via CAN communica-
tion, which operates the oil pressure gauge in the combination meter.
SEIA0745E
Flickering
pattern Items Diagnostic items detected when··· Check item
15 Tire pressure value (Front LH) Front LH tire pressure drops to 181 kPa (1.8 kg/cm, 25.25 psi) or less.
–
16 Tire pressure value (Front RH) Front RH tire pressure drops to 181 kPa (1.8 kg/cm, 25.25 psi) or less.
17 Tire pressure value (Rear RH) Rear RH tire pressure drops to 181 kPa (1.8 kg/cm, 25.25 psi) or less.
18 Tire pressure value (Rear LH) Rear LH tire pressure drops to 181 kPa (1.8 kg/cm, 25.25 psi) or less.
21 Transmitter no data (Front LH) Data from front LH transmitter can not be received.
WT-27
22 Transmitter no data (Front RH) Data from front RH transmitter can not be received.
23 Transmitter no data (Rear RH) Data from Rear RH transmitter can not be received.
24 Transmitter no data (Rear LH) Data from Rear LH transmitter can not be received.
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BCS-28
< FUNCTION DIAGNOSIS >[BCM]
DIAGNOSIS SYSTEM (BCM)
ERASE SELF-DIAGNOSIS
With CONSULT-III
1. Perform applicable inspection of malfunctioning item and then repair or replace.
2. Turn ignition switch “ON” and select “SELF-DIAG
RESULTS” mode for “AIR PRESSURE MONITOR” with
CONSULTIII.
3. Touch “ERASE” on CONSULT-III screen to erase memory.
Without CONSULT-III
In order to make it easier to find the cause of hard-to-duplicate malfunctions, malfunction information is
stored into the control unit as necessary during use by the user. This memory is not erased no matter how
many times the ignition switch is turned “ON” and“OFF”.
However, this information is erased by turning igniti on switch “OFF” after performing self-diagnostic or by
erasing the memory using the CONSULT-III.
AIR PRESSURE MONITOR : CONSULT-III FunctionINFOID:0000000003776405
WORK SUPPORT MODE
31Transmitter ch
ecksum error
(Front LH) Checksum data from front LH transmitter is malfunctioning.
WT-27
32Transmitter ch
ecksum error
(Front RH) Checksum data from front RH transmitter is malfunctioning.
33 Transmitter ch
ecksum error
(Rear RH) Checksum data from rear RH transmitter is malfunctioning.
34 Transmitter ch
ecksum error
(Rear LH) Checksum data from rear RH transmitter is malfunctioning.
35 Transmitter pressure data error
(Front LH) Air pressure data from front LH transmitter is malfunction.
WT-27
36Transmitter pressure data error
(Front RH) Air pressure data from front RH transmitter is malfunction.
37 Transmitter pressure data error
(Rear RH)
Air pressure data from rear RH transmitter is malfunction.
38 Transmitter pressure data error
(Rear LH) Air pressure data from rear LH transmitter is malfunction.
41 Transmitter function code error
(Front LH) Function code data from front LH transmitter is malfunction.
WT-27
42Transmitter function code error
(Front RH)
Function code data from front RH transmitter is malfunction.
43 Transmitter function code error
(Rear RH) Function code data from rear RH transmitter is malfunction.
44 Transmitter function code error
(Rear LH) Function code data from rear LH transmitter is malfunction.
45 Transmitter battery voltage low
(Front LH)
Battery voltage of front LH transmitter drops.
WT-27
46Transmitter battery voltage low
(Front RH) Battery voltage of front RH transmitter drops.
47 Transmitter battery voltage low
(Rear RH) Battery voltage of rear RH transmitter drops.
48 Transmitter battery voltage low
(Rear LH)
Battery voltage of rear LH transmitter drops.
52 Vehicle speed signal error Speed signal is not detected. WT-27
No flicker-
ing Tire pressure warning check
switch
Tire pressure warning sw
itch circuit is open. –
Flickering
pattern Items Diagnostic items detected when··· Check item
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BCS
DIAGNOSIS SYSTEM (BCM)BCS-29
< FUNCTION DIAGNOSIS > [BCM]
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ID Read
The registered ID number is displayed.
ID Regist
Refer to
WT-6, "ID Registration Procedure".
SELF-DIAG RESULTS MODE
Operation Procedure
Refer to WT-12, "Self-Diagnosis (With CONSULT-III)".
DATA MONITOR MODE
Screen of data monitor mode is displayed. Refer to WT-11, "CONSULT-III Function (BCM)".
NOTE:
When malfunction is detected, CONSUL T-III perform REAL-TIME DIAGNOSIS.
Also, any malfunction detected while in this mode will be displayed at real time.
ACTIVE TEST MODE
NOTE:
Before performing the self-diagnosis, be sure to register the ID, or else the actual malfunction may be different
from that displayed on CONSULT-III.
TEST ITEM LIST
THEFT ALM
THEFT ALM : CONSULT-III Function (BCM - THEFT ALM)INFOID:0000000003776406
WORK SUPPORT
Test item Content
WARNING LAMP This test is able to check to make sure that the warning lamp turns on.
ID REGIST WARNING This test is able to check to make sure that the buzzer sounds or the warning lamp turns on.
FLASHER This test is able to check to make sure that each turn signal lamp turns on.
HORN This test is able to check to make sure that the horn sounds.
Work Item Description
SECURITY ALARM SET Vehicle security function mode can be changed in this mode.
ON: Vehicle security function is ON.
OFF: Vehicle security function is OFF.
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BCS-30
< COMPONENT DIAGNOSIS >[BCM]
U1000 CAN COMM CIRCUIT
COMPONENT DIAGNOSIS
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000003776407
Refer to
LAN-44, "CAN Communication Signal Chart".
DTC LogicINFOID:0000000003776408
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000003776409
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)
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BCS
U1010 CONTROL UNIT (CAN)BCS-31
< COMPONENT DIAGNOSIS > [BCM]
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U1010 CONTROL UNIT (CAN)
DTC LogicINFOID:0000000003776410
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000003776411
1. REPLACE BCM
When “DTC:U1010” is detected, replace BCM.
>> Replace BCM. Refer to BCS-56, "Removal and Installation"
.
Special Repair RequirementINFOID:0000000003776412
1. ADDITIONAL SERVICE WHEN REPLACING BCM
>> Refer to BCS-3, "ADDITIONAL SERVICE WHEN RE PLACING CONTROL UNIT : Special Repair
Requirement".
DTCCONSULT-III display de-
scription DTC Detection Condit
ion Possible cause
U1010 CONTROL UNIT (CAN) When detecting error during the initial diagnosis of CAN control-
ler of BCM.
BCM
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BCS-32
< COMPONENT DIAGNOSIS >[BCM]
POWER SUPPLY AND GROUND CIRCUIT
POWER SUPPLY AND GROUND CIRCUIT
Diagnosis ProcedureINFOID:0000000003776413
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 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
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BCS
COMBINATION SWITCH INPUT CIRCUITBCS-33
< COMPONENT DIAGNOSIS > [BCM]
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COMBINATION SWITCH
INPUT CIRCUIT
Diagnosis ProcedureINFOID:0000000003776414
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 5 7
INPUT 3 4 10
INPUT 4 3 9
INPUT 5 2 8
ALMIA0275ZZ
System
BCM
GroundContinuity
Connector Terminal
INPUT 1
M186
No
INPUT 2 5
INPUT 3 4
INPUT 4 3
INPUT 5 2
ALMIA0276ZZ
System Te 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
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BCS-34
< COMPONENT DIAGNOSIS >[BCM]
COMBINATION SWITCH INPUT CIRCUIT
YES >> GO TO 4
NO >> Replace BCM. Refer to
BCS-56, "Removal and Installation"
.
4. CHECK COMBINATION SWITCH
Check combination switch. Refer to BCS-36, "Description"
.
Is the check result normal?
YES >> Replace BCM. Refer to BCS-56, "Removal and Installation".
NO >> Replace the combination switch (applicable parts). Refer to EXL-152, "Removal and Installation"
.
Special Repair RequirementINFOID:0000000003776415
1. ADDITIONAL SERVICE WHEN REPLACING BCM
>> Refer to BCS-3, "ADDITIONAL SERVICE WHEN RE PLACING CONTROL UNIT : Special Repair
Requirement".
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BCS
COMBINATION SWITCH OUTPUT CIRCUITBCS-35
< COMPONENT DIAGNOSIS > [BCM]
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COMBINATION SWITCH OUTPUT CIRCUIT
Diagnosis ProcedureINFOID:0000000003776416
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-56, "Removal and Installation".
NO >> Replace combination switch (applicable parts). Refer to EXL-152, "Removal and Installation"
.
Special Repair RequirementINFOID:0000000003776417
1. ADDITIONAL SERVICE WHEN REPLACING BCM
>> Refer to BCS-3, "ADDITIONAL SERVICE WHEN RE PLACING 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 35 2
OUTPUT 3 34 3
OUTPUT 4 33 4
OUTPUT 5 32 5
ALMIA0278ZZ
System
BCM
GroundContinuity
Connector Terminal
OUTPUT 1
M1836
No
OUTPUT 2 35
OUTPUT 3 34
OUTPUT 4 33
OUTPUT 5 32
ALMIA0279ZZ
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BCS-36
< COMPONENT DIAGNOSIS >[BCM]
COMBINATION SWITCH
COMBINATION SWITCH
DescriptionINFOID:0000000003776418
COMBINATION SWITCH MATRIX
Combination switch consists of INPUT circuit and OUTPUT circuit.
Combination switch circuit
Combination switch INPUT-OUTPUT system list
NOTE:
Headlamp has a dual system switch.
Diagnosis ProcedureINFOID:0000000003776419
1. CHECK LIGHT & TURN SIGNAL SWITCH
Check operation with normal light and turn signal switch installed.
Does it operate normally?
YES >> Replace light and turn signal switch. Refer to EXL-152, "Removal and Installation".
NO >> GO TO 2
2. CHECK WIPER & WASHER SWITCH
Check operation with normal wiper and washer switch installed.
Does it operate normally?
YES >> Replace wiper and washer switch. Refer to WW-80, "Wiper and Washer Switch".
System OUTPUT 1 OUTPUT 2 OUTPUT 3 OUTPUT 4 OUTPUT 5
INPUT 1 — FR WASHER FR WIPER LOW TURN LH TURN RH
INPUT 2 FR WIPER HI — FR WIPER INT PASSING HEADLAMP 1
INPUT 3 INT VOLUME 1 RR WASHER — HEADLAMP 2 HI BEAM
INPUT 4 RR WIPER INT INT VOLUME 3 AUTO LIGHT — TAIL LAMP
INPUT 5 INT VOLUME 2 RR WIPER — FR FOG —
LIIA0760E
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