INFINITI QX56 2011 Factory Service Manual

C1729 VEHICLE SPEED SIGNALWT-41
< DTC/CIRCUIT DIAGNOSIS >
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C1729 VEHICLE SPEED SIGNAL
DTC LogicINFOID:0000000006225516
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
With CONSULT-III
1. Drive for 3 minutes at a speed of 40 km/h (25 MPH) or more without stopping.
2. Stop the vehicle.
3. Perform self-diagnosis for “AIR PRESSURE MONITOR”.
Is DTC
“C1729” detected?
YES >> Proceed to WT-41, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006225517
1.PERFORM ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ABS”.
Is any DTC detected?
YES >> Check malfunctioning circuit.
NO >> GO TO 2.
2.PERFORM SELF-DIAGNOSIS AGAIN
With CONSULT-III
Perform “DTC CONFIRMATION PROCEDURE” (self-diagnosis) again. Refer to WT-41, "
DTC Logic".
Is DTC
“C1729” detected?
YES >> Replace the low tire pressure warning control unit. Refer to WT-65, "Removal and Installation".
NO >> GO TO 3.
3.CHECK LOW TIRE PRESSURE WARNING CONTROL UNIT INPUT/OUTPUT SIGNAL
Check the low tire pressure warning control unit input/output signal values. Refer to WT-14, "
Reference
Va l u e".
Is the inspection result normal?
YES >> Check pin terminal and connection of each harness connector for malfunctioning conditions.
NO >> Replace the low tire pressure warning control unit. Refer to WT-65, "
Removal and Installation".
DTC Display Item Malfunction detected condition Possible causes
C1729 VHCL SPEED SIG ERR Vehicle speed signal not detected. CAN communication malfunction
 Low tire pressure warning control
unit malfunction
 ABS actuator and electric unit (control unit) malfunction
Revision: 2010 May2011 QX56

WT-42
< DTC/CIRCUIT DIAGNOSIS >
C1750, C1751, C1752, C1753 RECEIVER
C1750, C1751, C1752, C1753 RECEIVER
DTC LogicINFOID:0000000006225518
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION
With CONSULT-III
1. Drive for 3 minutes at a speed of 40 km/h (25 MPH) or more, then drive normally for 10 minutes.
2. Stop the vehicle.
3. Perform self-diagnosis for “AIR PRESSURE MONITOR”.
Is DTC
“C1750”, “C1751”, “C1752”, or “C1753” detected?
YES >> Proceed to WT-42, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006225519
1.CHECK TIRE PRESSURE RE CEIVER INPUT SIGNAL
1. Turn the ignition switch ON. CAUTION:
Never start engine.
2. Use an oscilloscope and check the input signal waveform between the low tire pressure warning control unit harness connector and ground.
STANDBY STATUS
DTC Display Item Malfunction detected condition Possible causes
C1750 [RECEIVER ERR] FL The front LH tire pressure receiver dose not re-
ceive a signal.
Tire pressure receiver mal-
function
C1751 [RECEIVER ERR] FR
The front RH tire pressure receiver dose not re-
ceive a signal.
C1752 [RECEIVER ERR] RR The rear RH tire pressure receiver dose not re-
ceive a signal.
C1753 [RECEIVER ERR] RL The rear LH tire pressure
receiver dose not receive
a signal.
Low tire pressure warning control unit
— Value (Approx.)
Connector Terminal
M96 3
Ground
Approx. 4.5 V
4
5
6
OCC3879D
Revision: 2010 May2011 QX56

C1750, C1751, C1752, C1753 RECEIVER
WT-43
< DTC/CIRCUIT DIAGNOSIS >
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WHEN SIGNAL IS RECEIVED
Is the inspection result normal?
YES >> Check connector for loose connection and t hen perform “DTC CONFIRMATION PROCEDURE”
(self-diagnosis) again. Refer to WT-42, "
DTC Logic".
NO >> GO TO 2.
2.CHECK TIRE PRESSURE RECE IVER POWER SUPPLY CIRCUIT
1. Disconnect the tire pressure receiver harness connector.
2. Turn the ignition switch ON. CAUTION:
Never start the engine.
3. Check the voltage between tire pressure receiver harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace the malfunctioning harness or connector.
3.CHECK TIRE PRESSURE RECEIVER GROUND CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect low tire pressure warning control unit harness connector and tire pressure receiver harness connector.
3. Check the continuity between low tire pressure warning control unit harness connector and tire pressure
receiver harness connector.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace the malfunctioning harness or connector.
4.CHECK FOR CHANGE TO THE TIRE PRESSURE RECEIVER INSTALLATION POSITION (EXAMPLE:
FRONT LH RECEIVER OK/NG JUDGMENT) NOTE:
Example: Front LH tire pressure receiver OK/NG judgment when DTC “C1750” is detected.
Low tire pressure warning control unit
— Value (Approx.)
Connector Terminal
M96 3
Ground
Approx. 4.5 V
4
5
6
OCC3880D
Tire pressu
re receiver
—Voltage
Connector Terminal
E53 (Front LH)
1 Ground Approx. 9 - 16 V
E19 (Front RH)
B43 (Rear LH)
B212 (Rear RH)
Low tire pressure wa rning control unit Tire pressure receiver
Continuity
Connector Terminal Connector Terminal
M96 26 E53 (Front LH)
4 Existed
25 E19 (Front RH)
24 B43 (Rear LH)
23 B212 (Rear RH)
Revision: 2010 May2011 QX56

WT-44
< DTC/CIRCUIT DIAGNOSIS >
C1750, C1751, C1752, C1753 RECEIVER
With CONSULT-III
1. Exchange the positions of the front LH tire pressure receiver and the front RH tire pressure receiver.
2. Perform “DTC CONFIRMATION PROCE DURE” (self-diagnosis) again. Refer to WT-42, "
DTC Logic".
Is DTC
“C1751” detected?
YES >> Replace the exchanged front RH tire pressure receiver.
NO >> Check the low tire pressure warning control unit circuit. Refer to WT-45, "
Diagnosis Procedure".
Revision: 2010 May2011 QX56

C1754 LOW TIRE PRESSURE WARNING CONTROL UNIT
WT-45
< DTC/CIRCUIT DIAGNOSIS >
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C1754 LOW TIRE PRESSURE WARNING CONTROL UNIT
DTC LogicINFOID:0000000006225520
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION
With CONSULT-III
1. Drive for 3 minutes at a speed of 40 km/h (25 MPH) or more without stopping.
2. Stop the vehicle.
3. Perform self-diagnosis for “AIR PRESSURE MONITOR”.
Is DTC
“C1754” detected?
YES >> Proceed to WT-45, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006225521
1.CHECK LOW TIRE PRESSURE WARNING CONT ROL UNIT POWER SUPPLY AND GROUND CIRCUIT
Perform the trouble diagnosis for power supply and ground circuit. Refer to WT-51, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.CHECK TIRE PRESSURE RECEIVER CIRCUIT
1. Disconnect the tire pressure receiver harness connector.
2. Check the continuity between the low tire pressure warning control unit harness connector and tire pres-
sure receiver harness connector.
DTC Display Item Malfunction detected condition Possible causes
C1754 CONT UNIT (EEPROM) Memory (EEPROM) syst
em malfunction is
detected in the low tire pressure warning
control unit Low tire pressure warning con-
trol unit malfunction
Low tire pressure wa
rning control unit Tire pressure receiver
Continuity
Connector Terminal Connector Terminal
M96 6
E53 (Front LH) 3
Existed
22 2
10 1
26 4
5
E19 (Front RH) 3
21 2 91
25 4 4
B43 (Rear LH) 3
20 2 81
24 4 3
B212 (Rear RH) 3
19 2 71
23 4
Revision: 2010 May2011 QX56

WT-46
< DTC/CIRCUIT DIAGNOSIS >
C1754 LOW TIRE PRESSURE WARNING CONTROL UNIT
3. Check the continuity between the low tire pres sure warning control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace the ma lfunctioning harness or connector.
3.PERFORM SELF-DIAGNOSIS AGAIN
With CONSULT-III
1. Check the tire pressure for all wheels and adjust to the specified value. Refer to WT-69, "
Tire Air Pres-
sure".
2. Perform transmitter ID registration for all wheels. Refer to WT-29, "
Work Procedure".
3. Perform “DTC CONFIRMATION PROCE DURE” (self-diagnosis) again. Refer to WT-45, "
DTC Logic".
Is DTC
“C1754” detected?
YES >> Replace the low tire pressure warning control unit. Refer to WT-65, "Removal and Installation".
NO >> Check for looseness or damage at the harness connec tor pins of the low tire pressure warning
control unit. Repair or replace if necessary.
Low tire pressure warning control unit
— Continuity
Connector Terminal
M96 6
Ground Not existed
22
10
26
5
21 9
25 4
20 8
24 3
19 7
23
Revision: 2010 May2011 QX56

C1755, C1756, C1757, C1758 POOR RECEIVING CONDITIONS
WT-47
< DTC/CIRCUIT DIAGNOSIS >
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C1755, C1756, C1757, C1758 PO OR RECEIVING CONDITIONS
DTC LogicINFOID:0000000006225522
DTC DETECTION LOGIC
CAUTION:
If DTC C1755, C1756, C1757, or C1758 is detected al ong with, C1708, C1709, C1710, or C1711 first diag-
nose C1755, C1756, C1757, or C1758.
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION
With CONSULT-III
1. Drive for 3 minutes at a speed of 40 km/h (25 MPH) or more, then drive normally for 10 minutes.
2. Stop the vehicle.
3. Perform self-diagnosis for “AIR PRESSURE MONITOR”.
Is DTC
“C1755”, “C1756”, “C1757”, or “C1758 ” detected?
YES >> Proceed to WT-47, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006225523
1.TRANSMITTER ID REGISTRATION
Perform transmitter ID registration. Refer to WT-29, "
Work Procedure".
Is transmitter ID registration completed?
YES >> GO TO 2.
NO >> Change the work location and perform ID registration again, then proceed to WT-60,
"DiagnosisProcedure".
2.CHECK TIRE PRESSURE SIGNAL
With CONSULT-III
1. Drive for 3 minutes at a speed of 40 km/h (25 MPH) or more, then drive normally for 10 minutes.
2. Stop the vehicle.
3. Select “DATA MONITOR” for “AIR PRESSURE MONITOR” with CONSULT-III.
4. Within 5 minutes after vehicle stopped, check t hat the tire pressures match the standard value.
DTC Display Item Malfunction detected condition Possible causes
C1755 PR RECEIV COND FL The data signal from the front LH wheel transmitter cannot be
detected due to external electromagnetic interference for 10
minutes or more.
(DTC C1708 is displayed at the same time.)
External electromagnetic
interference
C1756 PR RECEIV COND FR
The data signal from the front RH wheel transmitter cannot be
detected due to external electromagnetic interference for 10
minutes or more.
(DTC C1709 is displayed at the same time.)
C1757 PR RECEIV COND RR The data signal from the rear RH wheel transmitter cannot be
detected due to external electromagnetic interference for 10
minutes or more.
(DTC C1710 is displayed at the same time.)
C1758 PR RECEIV COND RL The data signal from the rear LH wheel transmitter cannot be
detected due to external electromagnetic interference for 10
minutes or more.
(DTC C1711 is displayed at the same time.)
Monitor item Displayed value
AIR PRESS FL Approximately equal to the indication on tire gauge value for front LH tire
AIR PRESS FR Approximately equal to the indication on tire gauge value for front RH tire
Revision: 2010 May2011 QX56

WT-48
< DTC/CIRCUIT DIAGNOSIS >
C1755, C1756, C1757, C1758 POOR RECEIVING CONDITIONS
Is the inspection result normal?
YES >> GO TO 3.
NO >> Change the work location, then GO TO 1.
3.CHECK SELF-DIAGNOSIS RESULTS
With CONSULT-III
1. Erase the self-diagnosis memory for the low tire pressure warning control unit.
2. Turn ignition switch OFF, and wait for 10 seconds or more.
3. Perform “DTC CONFIRMATION PROCE DURE” (self-diagnosis) again. Refer to WT-47, "
DTC Logic".
Are DTC
“C1755”, “C1756”, “C1757”, or “C1758” and “C1708”, “C1709”, “C1710”, or “C1711” detected?
YES >> Change the work location, then GO TO 1.
NO >> Check the input/output signal values. Refer to WT-14, "
Reference Value".
AIR PRESS RR Approximately equal to the indica tion on tire gauge value for rear RH tire
AIR PRESS RL Approximately equal to the indicati on on tire gauge value for rear LH tire
Monitor item Displayed value
Revision: 2010 May2011 QX56

U1000 CAN COMM CIRCUITWT-49
< DTC/CIRCUIT DIAGNOSIS >
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U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006225524
CAN (Controller Area Network) is a serial communication li ne for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring.
Each control unit communicates data but selectively reads required data only.
DTC LogicINFOID:0000000006225525
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION
With CONSULT-III
1. Drive for several minutes at a speed of 40 km/h (25 MPH) or more.
2. Stop the vehicle.
3. Perform self-diagnosis for “AIR PRESSURE MONITOR”.
Is DTC
“U1000” detected?
YES >> Proceed to WT-49, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006225526
Proceed to LAN-27, "CAN COMMUNICATION SYSTEM : CA N System Specification Chart".
DTC Display item Malfunction detected condition Possible cause
U1000 CAN COMM CIRCUIT Low tire pressure warn
ing control unit is
not communicating CAN communication
signal for 2 seconds or more.  CAN communication malfunction
 Malfunction of low tire pressure warn-
ing control unit
Revision: 2010 May2011 QX56

WT-50
< DTC/CIRCUIT DIAGNOSIS >
U1010 CONTROL UNIT (CAN)
U1010 CONTROL UNIT (CAN)
DescriptionINFOID:0000000006225527
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication s peed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CA N communication, control units are connected with 2
communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring.
Each control unit communicates data but selectively reads required data only.
DTC LogicINFOID:0000000006225528
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION
With CONSULT-III
1. Drive for several minutes at a s peed of 40 km/h (25 MPH) or more.
2. Stop the vehicle.
3. Perform self-diagnosis for “AIR PRESSURE MONITOR”.
Is DTC
“U1010” detected?
YES >> Proceed to WT-50, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006225529
1.CHECK LOW TIRE PRESSURE WARNING CONTROL UNIT
Check low tire pressure warning control uni t harness connector for disconnection or deformation.
Is the inspection result normal?
YES >> Replace low tire pressure warning control unit. Refer to WT-65, "Removal and Installation".
NO >> Repair or replace error-detected parts.
DTC Display item Malfunction detected condition Possible cause
U1010 CONTROL UNIT (CAN) Detecting error during the initial diagno-
sis of CAN controller of low tire pressure
warning control unit.Malfunction of low tire pressure warning
control unit
Revision: 2010 May2011 QX56