ECU INFINITI QX56 2011 Factory Service Manual

DIAGNOSIS SYSTEM (PRE-CRASH SEAT BELT)SBC-11
< SYSTEM DESCRIPTION >
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DIAGNOSIS SYSTEM (P RE-CRASH SEAT BELT)
CONSULT-III FunctionINFOID:0000000006237882
Diagnosis for pre-crash seat belt syst em can be performed using CONSULT-III.
APPLICATION ITEM
SELF-DIAGNOSIS RESULTS
Refer to SBC-16, "DTC Index".
CAUTION:
When malfunctions are detect ed in several systems, includin g CAN communication [U1000], trouble-
shoot CAN communication [U1000].
A malfunction of system may be disp layed when battery voltage is low (when 7 to 8 V is continued for
approximately 2 seconds) even though the system is not malfunctioning. Erase DTC memory and
never replace any parts after making sure that the syst em is normal, especially if the malfunctions are
displayed after replacing battery.
ERASING SELF-DIAGNOSIS RESULTS
 SELF-DIAGNOSIS RESULTS Current “SELF-DIAG RESULTS” are displayed. (If all suspect circuits have been repaired, “NO DTC” is dis-
played.)
DATA MONITOR
Part to be diagnosed Diagnosis Mode Function description
Pre-crash seat belt Self-diagnosis Results
 Displays data recorded when a malfunction is de-
tected.
 Erases DTC recorded in memory.
Data Monitor Displays input data for pre-crash seat belt control
unit in real time.
Work Support Changes the setting for each system function.
CAN DIAG SUPPORT MNTR Monitors communication status of CAN communi-
cation.
Ecu Identification Displays pre-crash seat belt control unit part num-
ber.
Monitor item Contents
BUCKLE SW RH Indicates [ON/OFF] condition of seat belt buckle switch (RH).
BUCKLE SW LH Indicates [ON/OFF] condition of seat belt buckle switch (LH).
VEHICLE DISTANCE Indicates [ON/OFF] condit ion of intelligent brake assist signal.
IGN SW Indicates [ON/OFF] condition of ignition switch.
FR DOOR SW RH Indicates [Close/Open] condition of front door switch (RH).
FR DOOR SW LH Indicates [Close/Open] condition of front door switch (LH).
ABS ACTIVATING Indicates [ON/OFF] co ndition of ABS operation signal.
VHCL SPEED Indicates [Km/h] vehicle speed signal.
BRK PEDAL SNSR1 Indicates [V] voltage of brake pedal stroke sensor 1 signal.
BRK PEDAL SNSR2 Indicates [V] voltage of brake pedal stroke sensor 2 signal.
STRG ANGLE Indicates [deg] steering angle signal.
STRG ANGLE SPEED Indicates [deg/s] steering angle speed signal.
INCLINATION JDMT Indicates [ON/OFF] condition of pre roll over signal.
PRE-TEN ACTIVTN Indicates [ON/OFF] condition of pre-tensioner operated signal.
HEAT PROTC RH Indicates [ON/OFF] condition of heat protection (RH).
HEAT PROTC LH Indicates [ON/OFF] condition of heat protection (LH).
Revision: 2010 May2011 QX56

PRE-CRASH SEAT BELT CONTROL UNIT (DRIVER SIDE)SBC-13
< ECU DIAGNOSIS INFORMATION >
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ECU DIAGNOSIS INFORMATION
PRE-CRASH SEAT BELT CONTROL UNIT (DRIVER SIDE)
Reference ValueINFOID:0000000006237883
VALUES ON THE DIAGNOSIS TOOL
CONSULT-III MONITOR ITEM
Monitor item Condition Value/Status
(Approx.)
BUCKLE SW RH RH seat belt is not fastened OFF
RH seat belt is fastened ON
BUCKLE SW LH RH seat belt is not fastened OFF
RH seat belt is fastened ON
VEHICLE DISTANCE Not activated OFF
Activated ON
IGN SW Ignition switch OFF OFF
Ignition switch ON ON
FR DOOR SW RH LH door close CLOSE
LH door open OPEN
FR DOOR SW LH RH door close CLOSE
RH door open OPEN
ABS ACTIVATING ABS is inactive OFF
ABS is active ON
VHCL SPEED While driving Equival ent speedometer reading (km/h)
BRK PEDAL SNSR1 Brake released → depressed (1 V → 4 V)
BRK PEDAL SNSR2 Brake released → depressed (4 V → 1 V)
STRG ANGLE Steering wheel: 0
° (Neutral) ±2.5 (deg)
Steering wheel: 90 ° (Turned right) +90 (deg)
Steering wheel: 90 ° (Turned left) -90 (deg)
STRG ANGLE SPEED Steering wheel: Being turnedDepending on steering acceleration speed
(deg/s)
INCLINATION JDMT Vehicle is level OFF
Vehicle is inclined ON
PRE-TEN ACTIVTN Seat belt pre-tensioner is not activated OFF
Seat belt pre-tensioner is activated ON
HEAT PROTC RH RH heat protection is not activated OFF
RH heat protection is activated ON
HEAT PROTC LH LH heat protection is not activated OFF
LH heat protection is activated ON
Revision: 2010 May2011 QX56

SBC-14
< ECU DIAGNOSIS INFORMATION >
PRE-CRASH SEAT BELT CONTROL UNIT (DRIVER SIDE)
TERMINAL LAYOUT
PHYSICAL VALUES
Fail SafeINFOID:0000000006237884
 When a system malfunction is detected, deactivates a part of the system or all functions depending on the
malfunctioning part.
 When the malfunction condition recovers to the normal condition, the system returns to the normal opera-
tion.
JMHIA0711ZZ
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
1
(Y) Ground Power supply Input — Battery voltage
2
(G) Ground Brake pedal stroke sensor signal 1 Input Brake released
→ depressed 1 V - 4 V
4
(P) Ground CAN-L Input/
Output ——
6
(LG/R) Ground Seat belt buckle switch signal Input Seat belt is fastened 0 V
Seat belt is unfastened 5 V
8
(G) Ground Local Communication Line 2 Output IGN ON 5 V
9
(–) Ground Shield — — —
10
(R) Ground Brake pedal stroke sensor power circuit Output IGN ON 5 V
12
(B) Ground Brake pedal stroke sensor signal 2 Input Brake released
→ depressed 4 V - 1 V
14
(L) Ground CAN-H Input/
Output ——
16
(W) Ground Local Communication Line 1 Input/
Output ——
17
(W) Ground Brake pedal stroke sensor ground circuit — — 0 V
18
(B) Ground Ground — — 0 V
19
(W) Ground Motor drive circuit power supply Input — Battery voltage
20
(B) Ground Motor drive circuit ground — — 0 V
Revision: 2010 May2011 QX56

PRE-CRASH SEAT BELT CONTROL UNIT (DRIVER SIDE)SBC-15
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*1: The deactivation mode differs depending on the internal malfunctioning condition of control unit Display contents of CONSULT-III Fail-safe
U0126 STRG ANG SEN SIG Stops the operation in the conditions as per the following.
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
 A part of comfort function
U0428 STRG ANGL CAL Stops the operation in the conditions as per the following.
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
 A part of comfort function
U1000 CAN communication circuit Stops the operation in the conditions as per the following. *
1
 During emergency brake operation
 When ABS continuously operates
 When lateral slippage during cornering occurs
 When Intelligent brake assistance operates
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 A part or the whole comfort function
B2451 SEAT BLT MTR DR CIRC Fully deactivates the whole operation.
B2452 SEAT BLT MTR AS CIRC Deactivate s a part of comfort function.
B2453 BR_STROKE_SEN_CIRC Stops the operation in the conditions as per the following.
 During emergency brake operation
 When ABS continuously operates
 A part of comfort function
B2454 SEAT BLT PWR DR CIRC Fully deactivates the whole operation.
B2455 CONTROL UNIT DR Stops the operation in the conditions as per the following. *
1
 During emergency brake operation
 When ABS continuously operates
 When lateral slippage during cornering occurs
 When Intelligent brake assistance operates
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 A part or the whole comfort function
B2456 SEAT BLT PWR AS Deactivates a part of comfort function.
B2457 CONTROL UNIT AS Deactivates a part of comfort function.
B2458 LOCAL COMM Deactivates a part of comfort function.
B2461 VHCL SPEED SIGNAL Stops the operation in the conditions as per the following.
 During emergency brake operation
 When ABS continuously operates
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 When comfort function operates
B2463 ROLLOVER SIGNAL Stops the operation in the conditions as per the following.
 When the vehicle inclined excessively
 A part or the whole comfort function
B2466 DR/AS CONTROL UNIT Deactivates a part of comfort function.
B2470 SYS HEAT PROTC DR  Fully deactivates the whole operation.
 Operation return
- 1 time operation becomes possible after approximately 30 seconds
- Returns to the initial condition after approximately 8 minutes
Revision: 2010 May2011 QX56

SBC-16
< ECU DIAGNOSIS INFORMATION >
PRE-CRASH SEAT BELT CONTROL UNIT (DRIVER SIDE)
DTC Index
INFOID:0000000006237885
DTC Trouble diagnosis name
(CONSULT-III display) DTC detection condition Reference
U0126 STRG ANG SEN SIG Steering angle sensor malfunction is received SBC-33
U0428 STRG ANGL CAL Steering angle sensor calibration incomplete signal is receivedSBC-34
U1000 CAN COMM CIRCUITPre-crash seat belt control unit cannot transmit and receive CAN
communication signal for 2 seconds or more SBC-35
B2451 SEAT BLT MTR DR CIRC Motor or control unit malfunction
 Seat belt motor circuit is open or shorted
SBC-36
B2452 SEAT BLT MTR AS CIRC Motor or control unit malfunction
 Seat belt motor circuit is open or shorted SBC-37
B2453 BR_STROKE_SEN_CIRC
 Brake pedal stroke sensor malfunction
 Brake pedal stroke sensor circuit is open or shorted SBC-38
B2454 SEAT BLT PWR DR CIRC Motor power su
pply circuit is open or shortedSBC-41
B2455 CONTROL UNIT DR Malfunction in pre-crash seat belt control unit SBC-42
B2456 SEAT BLT PWR AS CIRC Motor power supply circuit is open or shortedSBC-43
B2457 CONTROL UNIT AS Malfunction in pre-crash seat belt control unit SBC-44
B2458 LOCAL COMM Local communication line open or shortedSBC-45
B2461 VHCL SPEED SIGNAL Vehicle speed signal malfunction is received SBC-47
B2463 ROLLOVER SIGNAL Rollover signal malfunction is received SBC-48
B2466 DR/AS CONTROL UNIT Control unit is out of the vehicle specificationSBC-49
B2470 SYS HEAT PROTC DRDeactivation for cooling to prevent system heating due to continuous
operation SBC-50
B2471 SYS HEAT PROTC ASDeactivation for cooling to prevent system heating due to continuous
operation
SBC-51
Revision: 2010 May2011 QX56

PRE-CRASH SEAT BELT CONTROL UNIT (PASSENGER SIDE)
SBC-17
< ECU DIAGNOSIS INFORMATION >
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PRE-CRASH SEAT BELT CONTROL UNIT (PASSENGER SIDE)
Reference ValueINFOID:0000000006237886
TERMINAL LAYOUT
PHYSICAL VALUES
Fail SafeINFOID:0000000006237887
 When a system malfunction is detected, deactivates a part of the system or all functions depending on the
malfunctioning part.
 When the malfunction condition recovers to the norma l condition, the system returns to the normal opera-
tion.
JMHIA0711ZZ
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
1
(Y) Ground Power supply Input — Battery voltage
6
(LG/B) Ground Seat belt buckle switch signal Input Seat belt is fastened 0 V
Seat belt is unfastened 5 V
8
(G) Ground Local Communication Line 2 Input/
Output IGN ON 5 V
9
(–) Ground Shield — — —
16
(W) Ground Local Communication Line 1
Input/
Output ——
18
(B) Ground Ground — — 0 V
19
(W) Ground Motor passenger circuit power supply Input — Battery voltage
20
(B) Ground Motor passenger circuit ground — — 0 V
Display contents of CONSULT-III Fail-safe
U0126 STRG ANG SEN SIG Stops the operation in the conditions as per the following.
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
U0428 STRG ANGL CAL Stops the operation in the conditions as per the following.
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
Revision: 2010 May2011 QX56

SBC-18
< ECU DIAGNOSIS INFORMATION >
PRE-CRASH SEAT BELT CONTROL UNIT (PASSENGER SIDE)
*1: The deactivation mode differs depending on the internal malfunctioning condition of control unit
U1000 CAN communication circuit
Stops the operation in the conditions as per the following. *
1
 During emergency brake operation
 When ABS continuo
usly operates
 When lateral slippage during cornering occurs
 When Intelligent brake assistance operates
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 A part or the whole comfort function
B2452 SEAT BLT MTR AS CIRC Fully deactivates the whole operation.
B2453 BR_STROKE_SEN_CIRC Stops the operation in the conditions as per the following.
 During emergency brake operation
 When ABS continuo
usly operates
B2455 CONTROL UNIT DR Stops the operation in the conditions as per the following. *
1
 During emergency brake operation
 When ABS continuo
usly operates
 When lateral slippage during cornering occurs
 When Intelligent brake assistance operates
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 A part or the whole comfort function
B2456 SEAT BLT PWR AS Fully deactivates the whole operation.
B2457 CONTROL UNIT AS Fully deactivates the whole operation.*
1
B2458 LOCAL COMM
Fully deactivates the whole operation.*1
B2461 VHCL SPEED SIGNALStops the operation in the conditions as per the following.
 During emergency brake operation
 When ABS continuo
usly operates
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 A part or the whole comfort function
B2463 ROLLOVER SIGNAL When the vehicle inclined excessively
B2466 DR/AS CONTROL UNIT Stops the operation in the conditions as per the following.
 During emergency brake operation
 When ABS continuo
usly operates
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 A part or the whole comfort function
B2471 SYS HEAT PROTC AS  Fully deactivates the whole operation.
 Operation return
- 1 time operation becomes possible after approximately 30 seconds
- Returns to the initial condition after approximately 8 minutes
Display contents of CONSULT-III Fail-safe
Revision: 2010 May2011 QX56

SCS-2
ACCUMULATOR ......................................................34
ACCUMULATOR : Exploded View .........................35
ACCUMULATOR : Removal and Installation ..........35
ACCUMULATOR : Inspection ................................38
ACCUMULATOR : Disposal ...................................38
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE ...38
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE
: Exploded View ......................................................
39
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE
: Removal and Installation ......................................
39
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE
: Inspection .............................................................
43
PPMU, MIDDLE TUBE ASSEMBLY, PPMU PIPE
: Disposal ................................................................
43
REAR TUBE ASSEMBLY ...................................... ...43
REAR TUBE ASSEMBLY : Exploded View ............44
REAR TUBE ASSEMBLY : Removal and Installa-
tion ....................................................................... ...
44
REAR TUBE ASSEMBLY : Inspection ...................46
AIR LEVELIZER CONTROL SYSTEM
PRECAUTION ....... ....................... ...............
47
PRECAUTIONS .............................................. ...47
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. ...
47
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect ..................................
47
Precaution for Procedure without Cowl Top Cover ...48
Precaution for Air Levelizer Control System ...........48
SYSTEM DESCRIPTION ............................49
DESCRIPTION ................................................ ...49
Description ........................................................... ...49
COMPONENT PARTS .......................................50
Component Parts Location .................................. ...50
Component Description ..........................................50
Air Levelizer Control Module ..................................51
Vehicle Height Sensor ............................................51
Air Compressor .......................................................51
Air Compressor Relay ............................................51
CK SUSP Indicator Lamp .......................................51
STRUCTURE AND OPERATION ......................52
Rear Shock Absorber .......................................... ...52
Vehicle Height Sensor ............................................53
SYSTEM .......................................................... ...54
System Diagram .................................................. ...54
System Description .................................................54
Fail-safe ..................................................................55
DIAGNOSIS SYSTEM (AIR LEVELIZER
CONTROL MODULE) ........................................
56
CONSULT-III Function ........................................ ...56
ECU DIAGNOSIS INFORMATION .............58
AIR LEVELIZER CONTROL MODULE .......... ...58
Reference Value .................................................. ...58
Fail-safe ..................................................................59
DTC Inspection Priority Chart .................................59
DTC Index ...............................................................59
WIRING DIAGRAM ....................................61
AIR LEVELIZER CONTROL SYSTEM ........... ...61
Wiring Diagram .................................................... ...61
BASIC INSPECTION ..................................65
DIAGNOSIS AND REPAIR WORKFLOW ...... ...65
Work Flow ............................................................ ...65
Diagnostic Work Sheet ...........................................66
STANDARD VEHICLE HEIGHT SETTING .......67
Description ........................................................... ...67
Work Procedure ......................................................67
DTC/CIRCUIT DIAGNOSIS ........................69
C1801 VHCL HEIGHT SENSOR .................... ...69
DTC Logic ............................................................ ...69
Diagnosis Procedure ..............................................69
Component Inspection ............................................70
C1802 AIR SUS COMPRS RELAY ...................72
DTC Logic ............................................................ ...72
Diagnosis Procedure ..............................................72
C1803 AIR SUSPENSION EXH SOL ................74
DTC Logic ............................................................ ...74
Diagnosis Procedure ..............................................74
Component Inspection ............................................75
C1804 VHCL HEIGHT ADJ UP .........................77
DTC Logic ............................................................ ...77
Diagnosis Procedure ..............................................77
Component Inspection (Air Compressor Relay) .....79
Component Inspection (Air Compressor) ............. ...79
C1805 VHCL HEIGHT ADJ DOWN ...................80
DTC Logic ............................................................ ...80
Diagnosis Procedure ..............................................80
C1806 VHCL HEIGHT SEN FIX ........................81
DTC Logic ............................................................ ...81
Diagnosis Procedure ...............................................81
C1807 VHCL HEIGHT SEN VOLT ....................82
DTC Logic ............................................................ ...82
Diagnosis Procedure ..............................................82
C1808 AIR SUS COMPRS FNCTN ...................84
DTC Logic ............................................................ ...84
Diagnosis Procedure ..............................................84
U1000 CAN COMM CIRCUIT ............................87
Revision: 2010 May2011 QX56

CHECK SYSTEM PRESSURESCS-15
< BASIC INSPECTION > [HBMC]
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BASIC INSPECTION
CHECK SYSTEM PRESSURE
Work ProcedureINFOID:0000000006256009
CAUTION:
 Clean surrounding areas of oil inj ection jack using steam before starting operation, since there may
be mud on it.
 Clean oil pressure gauge (special service tool: KV40108000) jack with steam before use.
1. Lift up the vehicle.
2. Remove protector of PPMU.
3. Remove cap of oil injection jack.
4. Install an oil pressure gauge (SST: KV40108000) (A) to oil injec- tion jack.
CAUTION:
 Jack must be securely inserted until a click sound can be
heard.
 Pressure reducing valve (B) of the oil pressure gauge
must be closed.
5. Loosen needle valves A, C, and E of PPMU by approximately 2 rotations.
CAUTION:
Never loosen the needle valve more than required.
6. Refer to the figure and check the specified pressure.
7. Tighten needle valves A, C, and E of PPMU to the specified torque.
JSEIA0186ZZ
JSEIA0187ZZ
Tightening torque : 8.3 N·m (0.85 kg-m, 73 in-lb)
JSEIA0222GB
Revision: 2010 May2011 QX56

PRESSURE REDUCING METHODSCS-17
< BASIC INSPECTION > [HBMC]
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PRESSURE REDUCING METHOD
Work ProcedureINFOID:0000000006256010
CAUTION:
 Clean surrounding areas of oil inj ection jack using steam before starting operation, since there may
be mud on it.
 Clean oil pressure gauge (special service tool: KV40108000) jack with steam before use.
1. Lift up the vehicle.
2. Remove protector of PPMU.
3. Remove cap of oil injection jack.
4. Install an oil pressure gauge (SST: KV40108000) (A) to oil injec- tion jack.
CAUTION:
 Jack must be securely inserted until a click sound can beheard.
 Pressure reducing valve (B) of the oil pressure gauge
must be closed.
5. Loosen needle valves A, C, and E of PPMU by approximately 2 rotations.
CAUTION:
Never loosen the needle valve more than required.
6. Loosen pressure reducing valve (A) of oil pressure gauge and then lower pressure.
CAUTION:
Be careful since oil drains sw iftly from oil drain hole (B).
7. Check that reading of oil pressure gauge is 0 MPa.
8. Tighten needle valves A, C, and E of PPMU to the specified torque.
JSEIA0186ZZ
JSEIA0187ZZ
Tightening torque : 8.3 N·m (0.85 kg-m, 73 in-lb)
JSEIA0188ZZ
Revision: 2010 May2011 QX56