
ADP-56
< DTC/CIRCUIT DIAGNOSIS >
U1000 CAN COMM CIRCUIT
DTC/CIRCUIT DIAGNOSIS
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006248336
CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Modern
vehicle is equipped with many electronic control unit, 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) al lowing a high rate of information transmission with less
wiring. Each control unit transmits/receives data but selectively reads required data only.
DTC LogicINFOID:0000000006248337
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.STEP 1
Turn ignition switch ON and wait at least 3 seconds.
>> GO TO 2.
2.STEP 2
Check “Self diagnostic result” with CONSULT-III.
Is the DTC detected?
YES >> Perform diagnosis procedure. Refer to ADP-56, "DiagnosisProcedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006248338
Refer to LAN-18, "Trouble Diagnosis Flow Chart".
Special Repair RequirementINFOID:0000000006248339
Refer to ADP-52, "SYSTEM INITIALIZATION : Description".
DTC No. CONSULT-III display
description DTC detecting condition Possible cause
U1000 CAN COMM CIR-
CUIT Driver seat control unit cannot communicate to other
control units.
When driver seat control unit cannot communicate CAN communication signal continuously for 2 seconds or
more. CAN communication system
Revision: 2010 May2011 QX56

AV-118
< DTC/CIRCUIT DIAGNOSIS >
U1000 CAN COMM CIRCUIT
DTC/CIRCUIT DIAGNOSIS
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006216248
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 independently). In CA N communication, control units are connected with 2
communication lines (CAN-H, CAN-L) allowing a high rate of information transmission with less wiring. Each
control unit transmits/receives data but selectively reads required data only.
CAN Communication Signal Chart. Refer to LAN-28, "
CAN COMMUNICATION SYSTEM : CAN Communica-
tion Signal Chart".
DTC LogicINFOID:0000000006216249
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000006216250
1.PERFORM SELF-DIAGNOSTIC
1. Turn ignition switch ON and wait for 2 seconds or more.
2. Check “Self Diagnostic Result” of “MULTI AV”.
Is
“CAN COMM CIRCUIT” displayed?
YES >> Refer to LAN-18, "Trouble Diagnosis Procedure".
NO >> Refer to GI-40, "
Intermittent Incident".
DTCDisplay contents of CON-
SULT-III DTC detection condition Probable malfunction location
U1000 CAN COMM CIRCUIT
[U1000] AV control unit is not transmitting or receiving
CAN communication signal for 2 seconds or
more.
CAN communication system.
Revision: 2010 May2011 QX56

BCS-70
< DTC/CIRCUIT DIAGNOSIS >
U1000 CAN COMM
DTC/CIRCUIT DIAGNOSIS
U1000 CAN COMM
DescriptionINFOID:0000000006274829
CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Modern
vehicle is equipped with many electronic control unit, 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) al lowing a high rate of information transmission with less
wiring. Each control unit transmits/receives data but selectively reads required data only.
CAN Communication Signal Chart. Refer to LAN-28, "
CAN COMMUNICATION SYSTEM : CAN Communica-
tion Signal Chart".
DTC LogicINFOID:0000000006274830
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000006274831
1.PERFORM SELF DIAGNOSTIC
1. Turn ignition switch ON and wait for 2 seconds or more.
2. Check “Self Diagnostic Result” of BCM.
Is DTC
“U1000” displayed?
YES >> Refer to LAN-18, "Trouble Diagnosis Flow Chart".
NO >> Refer to GI-40, "
Intermittent Incident".
DTCCONSULT-III display
description DTC Detection Condition Possible cause
U1000 CAN COMM When BCM cannot communicate CAN com-
munication signal continuously for 2 seconds
or more.
CAN communication system
Revision: 2010 May2011 QX56
![INFINITI QX56 2011 Factory Service Manual
BRC-50
< ECU DIAGNOSIS INFORMATION >[WITH VDC]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
*1: Models with 4WD System
*2: Models with Advanced Driver Assistance System
Protection FunctionINFOID:000 INFINITI QX56 2011 Factory Service Manual
BRC-50
< ECU DIAGNOSIS INFORMATION >[WITH VDC]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
*1: Models with 4WD System
*2: Models with Advanced Driver Assistance System
Protection FunctionINFOID:000](/manual-img/42/57033/w960_57033-566.png)
BRC-50
< ECU DIAGNOSIS INFORMATION >[WITH VDC]
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
*1: Models with 4WD System
*2: Models with Advanced Driver Assistance System
Protection FunctionINFOID:0000000006222581
The VDC warning lamp, ABS warning lamp and brake warning lamp turns ON and DTC “C118E” may be
detected in self-diagnosis result of “ABS” when the br
ake pedal is excessively operated, such as air bleeding.
This is not a system malfunction because this occurs due to the temporary decrease in accumulator fluid pres-
sure. The system returns to normal condition when the accu mulator fluid pressure reaches the specified pres-
sure with the ignition switch ON and the VDC warning lamp, ABS warning lamp, and brake warning lamp turn
OFF. After these steps, erase self-diagnos is results for “ABS” with CONSULT-III.
NOTE:
D T C “ C 1111 ” i s d e t e c t e d i n s e l f - d i agnosis results of “ABS” when the a ccumulator system has a malfunction.
DTC Inspection Priority ChartINFOID:0000000006222582
When multiple DTCs are displayed simultaneously, check one by one depending on the following priority list.
C1170 When the information in ABS actuator and electric unit (control unit) is not the same. The following functions are sus-
pended.
VDC function
TCS function
ABS function
hill start assist function
Brake limited slip differential
(BLSD) function
C118E When performing excessive brake pedal operation with the vehicle stopped. [When
accumulator fluid pressure reaches 11.43 MPa (114 bar, 116.6 kg/cm
2, 1657 psi) af-
ter reaching 17.3 MPa (173 bar, 176.5 kg/cm2, 2509 psi.] The following functions are sus-
pended.
VDC function
TCS function
ABS function
EBD function
hill start assist function
Brake limited slip differential
(BLSD) function
U1000 When CAN communication signal is not continuously received for 2 seconds or
more. The following functions are sus-
pended.
VDC function
TCS function
ABS function
hill start assist function
Brake limited slip differential
(BLSD) function
DTC Malfunction detected condition Fail-safe condition
DTC
VDC warning lamp
ABS warning lamp
Brake warning lamp Condition Description protection function
C118E ON When temporary decrease in accumulator fluid pres-
sure.
NOTE:
System is not malfunction. The following functions are suspended
temporarily
VDC function
TCS function
ABS function
EBD function
hill start assist function
Brake limited slip differential (BLSD)
function
Priority Detected item (DTC)
1 U1000 CAN COMM CIRCUIT
2 C1170 VARIANT CODING
Revision: 2010 May2011 QX56
![INFINITI QX56 2011 Factory Service Manual
BRC-112
< DTC/CIRCUIT DIAGNOSIS >[WITH VDC]
U1000 CAN COMM CIRCUIT
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006222638
CAN communication allows a high rate of information transmission through t INFINITI QX56 2011 Factory Service Manual
BRC-112
< DTC/CIRCUIT DIAGNOSIS >[WITH VDC]
U1000 CAN COMM CIRCUIT
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006222638
CAN communication allows a high rate of information transmission through t](/manual-img/42/57033/w960_57033-628.png)
BRC-112
< DTC/CIRCUIT DIAGNOSIS >[WITH VDC]
U1000 CAN COMM CIRCUIT
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000006222638
CAN communication allows a high rate of information transmission through the two communication lines
(CAN-H line and CAN-L line) connecting various control
units in the system. Each control unit transmits/
receives data but selectively reads required data only.
DTC LogicINFOID:0000000006222639
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK DTC DETECTION
With CONSULT-III
1. Turn the ignition switch OFF to ON.
2. Perform self-diagnosis for “ABS”.
Is DTC
“U1000” detected?
YES >> Proceed to diagnosis procedure. Refer to BRC-112, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222640
Go to LAN-18, "Trouble Diagnosis Flow Chart".
DTC Display Item Malfunction detected condition Possible causes
U1000 CAN COMM CIRCUIT When CAN communication signal is not continuously
received for 2 seconds or more CAN communication system mal-
function
Revision: 2010 May2011 QX56
![INFINITI QX56 2011 Factory Service Manual
CCS
ICC SENSORCCS-55
< ECU DIAGNOSIS INFORMATION > [ICC]
C
D
E
F
G H
I
J
K L
M B
N P A
Fail-safeINFOID:0000000006224286
If a malfunction occurs in the ICC sensor, ADAS cont rol unit cancels control, INFINITI QX56 2011 Factory Service Manual
CCS
ICC SENSORCCS-55
< ECU DIAGNOSIS INFORMATION > [ICC]
C
D
E
F
G H
I
J
K L
M B
N P A
Fail-safeINFOID:0000000006224286
If a malfunction occurs in the ICC sensor, ADAS cont rol unit cancels control,](/manual-img/42/57033/w960_57033-789.png)
CCS
ICC SENSORCCS-55
< ECU DIAGNOSIS INFORMATION > [ICC]
C
D
E
F
G H
I
J
K L
M B
N P A
Fail-safeINFOID:0000000006224286
If a malfunction occurs in the ICC sensor, ADAS cont rol unit cancels control, sounds a beep, and turns ON the
ICC system warning lamp in the combination meter.
DTC Inspection Priority ChartINFOID:0000000006224287
If multiple DTCs are detected simultaneously, che ck them one by one depending on the following DTC inspec-
tion priority chart.
DTC IndexINFOID:0000000006224288
NOTE:
The details of time display are as per the following.
- 0: The malfunctions that are detected now
CAN communication system (U1000, U1010)
- 1 - 39: It increases like 0 → 1 → 2 ··· 38 → 39 after returning to the normal condition whenever the ignition
switch OFF → ON. It returns to 0 when a malfunc tion is detected again in the process.
- If it is over 39, it is fixed to 39 unt il the self-diagnosis results are erased.
Other than CAN communication s ystem (Other than U1000, U1010)
- 1 - 49: It increases like 0 → 1 → 2 ··· 38 → 49 after returning to the normal condition whenever the ignition
switch OFF → ON. It returns to 0 when a malfunc tion is detected again in the process.
- If it is over 49, it is fixed to 49 unt il the self-diagnosis results are erased.
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
1
(W/G)
GroundIgnition power supply Input Ignition switch ON Battery voltage
3
(L) ITS communication-H — — —
4
(B) Ground — Ignition switch ON 0 V
6
(Y) ITS communication-L — — —
Priority Detected items (DTC)
1 U1000: CAN COMM CIRCUIT
U1010: CONTROL UNIT (CAN)
2 C1A50: ADAS MALFUNCTION
3 C1A01: POWER SUPPLY CIR
C1A02: POWER SUPPLY CIR 2
C1A12: LASER BEAM OFFCNTR
C1A16: RADAR STAIN
C1A18: LASER AIMING INCMP
C1A21: UNIT HIGH TEMP
C1A39: STRG SEN CIR
U0104: ADAS CAN CIR1
U0121: VDC CAN CIR2
U0126: STRG SEN CAN CIR1
U0405: ADAS CAN CIR2
U0415: VDC CAN CIR1
U0428: STRG SEN CAN CIR2
4 C1A00: CONTROL UNIT
Revision: 2010 May2011 QX56
![INFINITI QX56 2011 Factory Service Manual
CCS
U1000 CAN COMM CIRCUITCCS-145
< DTC/CIRCUIT DIAGNOSIS > [ICC]
C
D
E
F
G H
I
J
K L
M B
N P A
U1000 CAN COMM CIRCUIT
ADAS CONTROL UNIT
ADAS CONTROL UNIT : DescriptionINFOID:0000000006227995
CAN COM INFINITI QX56 2011 Factory Service Manual
CCS
U1000 CAN COMM CIRCUITCCS-145
< DTC/CIRCUIT DIAGNOSIS > [ICC]
C
D
E
F
G H
I
J
K L
M B
N P A
U1000 CAN COMM CIRCUIT
ADAS CONTROL UNIT
ADAS CONTROL UNIT : DescriptionINFOID:0000000006227995
CAN COM](/manual-img/42/57033/w960_57033-879.png)
CCS
U1000 CAN COMM CIRCUITCCS-145
< DTC/CIRCUIT DIAGNOSIS > [ICC]
C
D
E
F
G H
I
J
K L
M B
N P A
U1000 CAN COMM CIRCUIT
ADAS CONTROL UNIT
ADAS CONTROL UNIT : DescriptionINFOID:0000000006227995
CAN COMMUNICATION
CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-vehicle mul-
tiplex communication line with high data communicati on speed and excellent error detection ability. Modern
vehicle is equipped with many electronic control units , 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, CAN-L) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads the required data only.
CAN communication signal chart. Refer to LAN-28, "
CAN COMMUNICATION SYSTEM : CAN Communica-
tion Signal Chart".
ITS COMMUNICATION
ITS communication is a multiplex communication syste m. This enables the system to transmit and receive
large quantities of data at high speed by connec ting control units with 2 communication lines.
ITS communication lines adopt twisted-pair line st yle (two lines twisted) for noise immunity.
ADAS CONTROL UNIT : DTC LogicINFOID:0000000006227996
DTC DETECTION LOGIC
NOTE:
If “U1000” is detected, first diagnose the CAN communication system.
ADAS CONTROL UNIT : Diagnosis ProcedureINFOID:0000000006227997
1.PERFORM THE SELF-DIAGNOSIS
1. Turn the ignition switch ON.
2. Turn the MAIN switch of ICC system ON, and then wait for 30 seconds or more.
3. Perform “All DTC Readi ng” with CONSULT-III.
4. Check if the “U1000” is detected as the current ma lfunction in “Self Diagnostic Result” of “ICC/ADAS”.
Is
“U1000” detected as the current malfunction?
YES >> Refer to LAN-18, "Trouble Diagnosis Flow Chart".
NO >> Refer to GI-40, "
Intermittent Incident".
ICC SENSOR
ICC SENSOR : DescriptionINFOID:0000000006224409
ITS COMMUNICATION
ITS communication is a multiplex communication syste m. This enables the system to transmit and receive
large quantities of data at high speed by connec ting control units with 2 communication lines
ITS communication lines adopt twisted-pair line st yle (two lines twisted) for noise immunity.
ICC SENSOR : DTC LogicINFOID:0000000006224410
DTC DETECTION LOGIC
DTC
(On board
display) Trouble diagnosis name DTC detecting condition Possible causes
U1000 (100) CAN COMM CIRCUIT If ADAS control unit is not transmitting or receiv-
ing CAN communication signal or ITS communi-
cation signal for 2 seconds or more CAN communication system
ITS communication system
Revision: 2010 May2011 QX56
![INFINITI QX56 2011 Factory Service Manual
CCS-146
< DTC/CIRCUIT DIAGNOSIS >[ICC]
U1000 CAN COMM CIRCUIT
ICC SENSOR : Diagnosis Procedure
INFOID:0000000006224411
1.PERFORM THE SELF-DIAGNOSIS
1. Turn the ignition switch ON.
2. Turn the MAIN sw INFINITI QX56 2011 Factory Service Manual
CCS-146
< DTC/CIRCUIT DIAGNOSIS >[ICC]
U1000 CAN COMM CIRCUIT
ICC SENSOR : Diagnosis Procedure
INFOID:0000000006224411
1.PERFORM THE SELF-DIAGNOSIS
1. Turn the ignition switch ON.
2. Turn the MAIN sw](/manual-img/42/57033/w960_57033-880.png)
CCS-146
< DTC/CIRCUIT DIAGNOSIS >[ICC]
U1000 CAN COMM CIRCUIT
ICC SENSOR : Diagnosis Procedure
INFOID:0000000006224411
1.PERFORM THE SELF-DIAGNOSIS
1. Turn the ignition switch ON.
2. Turn the MAIN switch of ICC system ON, and then wait for 2 seconds or more.
3. Perform “All DTC Reading” with CONSULT-III.
4. Check if the “U1000” is detected as the current malfunction in “Self Diagnostic Result” of “LASER”.
Is
“U1000” detected as the current malfunction?
YES >> Refer to LAN-18, "Trouble Diagnosis Flow Chart".
NO >> Refer to GI-40, "
Intermittent Incident".
DTC Trouble diagnosis name DTC detecting condition Possible causes
U1000 CAN COMM CIRCUIT If ICC sensor is not transmitting or receiving ITS
communication signal for 2 seconds or more ITS communication system
Revision: 2010 May2011 QX56