Page 2376 of 3419
CAN SYSTEM (TYPE 3)
LAN-97
[CAN]
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Revision: October 20052005 QX56
CHECK SHEET
NOTE:
If “NG” is displayed on “INITIAL DIAG (Initial diagnosis)” or “CAN COMM” for the diagnosed control unit,
replace the control unit.
SKIB3364E
Page 2378 of 3419
CAN SYSTEM (TYPE 3)
LAN-99
[CAN]
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Revision: October 20052005 QX56
CHECK SHEET RESULTS (EXAMPLE)
NOTE:
If “NG” is displayed on “INITIAL DIAG (Initial diagnosis)” or “CAN COMM” for the diagnosed control unit,
replace the control unit.
Case 1
Check harness between TCM and driver seat control unit. Refer to LAN-115, "Circuit Check Between TCM
and Driver Seat Control Unit" .
SKIB3365E
PKIA8156E
Page 2385 of 3419
LAN-106
[CAN]
CAN SYSTEM (TYPE 3)
Revision: October 20052005 QX56
Case 8
Check display control unit circuit. Refer to LAN-120, "Display Control Unit Circuit Check" .
SKIB3372E
PKIA8163E
Page 2399 of 3419
![INFINITI QX4 2005 Factory Service Manual LAN-120
[CAN]
CAN SYSTEM (TYPE 3)
Revision: October 20052005 QX56
Display Control Unit Circuit CheckUKS001A3
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal INFINITI QX4 2005 Factory Service Manual LAN-120
[CAN]
CAN SYSTEM (TYPE 3)
Revision: October 20052005 QX56
Display Control Unit Circuit CheckUKS001A3
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal](/manual-img/42/57035/w960_57035-2398.png)
LAN-120
[CAN]
CAN SYSTEM (TYPE 3)
Revision: October 20052005 QX56
Display Control Unit Circuit CheckUKS001A3
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Check terminals and connector of display control unit for damage, bend and loose connection (control unit
side and harness side).
OK or NG
OK >> GO TO 2.
NG >> Repair terminal or connector.
2. CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect display control unit connector.
2. Check resistance between display control unit harness connec-
tor M95 terminals 25 (L) and 26 (P).
OK or NG
OK >> Replace display control unit.
NG >> Repair harness between display control unit and data
link connector.
BCM Circuit CheckUKS001A4
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Check terminals and connector of BCM for damage, bend and loose connection (control module side and
harness side).
OK or NG
OK >> GO TO 2.
NG >> Repair terminal or connector.
2. CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect BCM connector.
2. Check resistance between BCM harness connector M18 termi-
nals 39 (L) and 40 (P).
OK or NG
OK >> Replace BCM. Refer to BCS-20, "Removal and Installa-
tion of BCM" .
NG >> Repair harness between BCM and data link connector.25 (L) - 26 (P) : Approx. 54 - 66 Ω
SKIA6884E
39 (L) - 40 (P) : Approx. 54 - 66 Ω
SKIA6869E
Page 2403 of 3419
![INFINITI QX4 2005 Factory Service Manual LAN-124
[CAN]
CAN SYSTEM (TYPE 3)
Revision: October 20052005 QX56
CAN Communication Circuit CheckUKS001AB
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3 INFINITI QX4 2005 Factory Service Manual LAN-124
[CAN]
CAN SYSTEM (TYPE 3)
Revision: October 20052005 QX56
CAN Communication Circuit CheckUKS001AB
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3](/manual-img/42/57035/w960_57035-2402.png)
LAN-124
[CAN]
CAN SYSTEM (TYPE 3)
Revision: October 20052005 QX56
CAN Communication Circuit CheckUKS001AB
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Disconnect the following module and control unit connectors and check terminals for deformation, discon-
nection, looseness or damage.
–ECM
–A/T assembly
–Driver seat control unit
–Combination meter
–Display control unit
–BCM
–Steering angle sensor
–Front air control
–Transfer control unit
–ABS actuator and electric unit (control unit)
–IPDM E/R
OK or NG
OK >> GO TO 2.
NG >> Repair or replace as necessary.
2. CHECK HARNESS FOR SHORT CIRCUIT
With all module and control unit connectors disconnected, check
continuity between data link connector M22 terminals 6 (L) and 14
(P).
OK or NG
OK >> GO TO 3.
NG >> Repair harness.
3. CHECK HARNESS FOR SHORT CIRCUIT
Check continuity between data link connector M22 terminals 6 (L),
14 (P) and ground.
OK or NG
OK >> Check ECM and IPDM E/R. Refer to LAN-125, "ECM/
IPDM E/R INTERNAL CIRCUIT INSPECTION" .
NG >> Repair harness.
IPDM E/R Ignition Relay Circuit CheckUKS001AC
Check the following. If no malfunction is found, replace the IPDM E/R.
IPDM E/R power supply circuit. Refer to PG-26, "IPDM E/R Power/Ground Circuit Inspection" .
Ignition power supply circuit. Refer to PG-13, "IGNITION POWER SUPPLY — IGNITION SW. IN ON
AND/OR START" . 6 (L) - 14 (P) : Continuity should not exist.
PKIA2077E
6 (L) - Ground : Continuity should not exist.
14 (P) - Ground : Continuity should not exist.
PKIA2079E
Page 2410 of 3419
![INFINITI QX4 2005 Factory Service Manual CAN SYSTEM (TYPE 4)
LAN-131
[CAN]
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Revision: October 20052005 QX56
Work FlowUKS001NT
1. When there are no indications of “AUTO DRIVE POS.”, “BCM”, “HVAC”, “ALL INFINITI QX4 2005 Factory Service Manual CAN SYSTEM (TYPE 4)
LAN-131
[CAN]
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Revision: October 20052005 QX56
Work FlowUKS001NT
1. When there are no indications of “AUTO DRIVE POS.”, “BCM”, “HVAC”, “ALL](/manual-img/42/57035/w960_57035-2409.png)
CAN SYSTEM (TYPE 4)
LAN-131
[CAN]
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LAN
Revision: October 20052005 QX56
Work FlowUKS001NT
1. When there are no indications of “AUTO DRIVE POS.”, “BCM”, “HVAC”, “ALL MODE AWD/4WD” or
“IPDM E/R” on “SELECT SYSTEM” display of CONSULT-II, print the “SELECT SYSTEM”.
2. Print all the data of “SELF-DIAG RESULTS” for “ENGINE”, “A/T”, “ICC”, “AUTO DRIVE POS.”, “BCM”,
“HVAC”, “ALL MODE AWD/4WD”, “ABS” and “IPDM E/R” displayed on CONSULT-II.
3. Print all the data of “CAN DIAG SUPPORT MNTR” for “ENGINE”, “A/T”, “ICC”, “AUTO DRIVE POS.”,
“BCM”, “HVAC”, “ALL MODE AWD/4WD”, “ABS” and “IPDM E/R” displayed on CONSULT-II.
4. Attach the printed sheet of “SELECT SYSTEM”, “SELF-DIAG RESULTS” and “CAN DIAG SUPPORT
MNTR” onto the check sheet. Refer to LAN-133, "
CHECK SHEET" .
5. Based on the indications of “SELECT SYSTEM” and the results of “CAN DIAG SUPPORT MNTR”, puts a
check mark onto the items with “No indication”, “NG” or “UNKWN” in the check sheet table. Refer to LAN-
133, "CHECK SHEET" .
CAUTION:
“ALL MODE AWD/4WD” puts a check mark on the check
sheet when “Present” is “UNKWN” and “Past” is “0”.
PKIA2093E
PKIA8260E
PKIA8343E
SKIB3244E
Page 2411 of 3419
![INFINITI QX4 2005 Factory Service Manual LAN-132
[CAN]
CAN SYSTEM (TYPE 4)
Revision: October 20052005 QX56
NOTE:
If “NG” is displayed on “INITIAL DIAG (Initial diagnosis)” as “CAN DIAG SUPPORT MNTR” for the diag-
nosed control u INFINITI QX4 2005 Factory Service Manual LAN-132
[CAN]
CAN SYSTEM (TYPE 4)
Revision: October 20052005 QX56
NOTE:
If “NG” is displayed on “INITIAL DIAG (Initial diagnosis)” as “CAN DIAG SUPPORT MNTR” for the diag-
nosed control u](/manual-img/42/57035/w960_57035-2410.png)
LAN-132
[CAN]
CAN SYSTEM (TYPE 4)
Revision: October 20052005 QX56
NOTE:
If “NG” is displayed on “INITIAL DIAG (Initial diagnosis)” as “CAN DIAG SUPPORT MNTR” for the diag-
nosed control unit, replace the control unit.
The “CAN DIAG SUPPORT MNTR” items, which are not in check sheet table, are not related to diag-
nostic procedure on service manual.
So it is not necessary to check the status of the “CAN DIAG SUPPORT MNTR” items not in check
sheet table.
6. Check CAN communication line of the navigation system. Refer to AV-131, "
CAN Communication Line
Check" .
7. Attach the CAN DIAG SUPPORT MONITOR check sheet onto the check sheet. Refer to LAN-133,
"CHECK SHEET" .
8. Mark the “NG” or “UNKWN” item of the check sheet table with “v” from the result of CAN DIAG SUPPORT
MONITOR check sheet. Refer to LAN-133, "
CHECK SHEET" .
NOTE:
If “NG” is displayed on “CAN COMM” as “CAN DIAG SUPPORT MONITOR” for the diagnosed control
unit, replace the control unit. Refer to AV- 1 3 1 , "
CAN Communication Line Check" .
9. According to the check sheet results (example), start inspection. Refer to LAN-136, "
CHECK SHEET
RESULTS (EXAMPLE)" .
Page 2412 of 3419
CAN SYSTEM (TYPE 4)
LAN-133
[CAN]
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LAN
Revision: October 20052005 QX56
CHECK SHEET
NOTE:
If “NG” is displayed on “INITIAL DIAG (Initial diagnosis)” or “CAN COMM” for the diagnosed control unit,
replace the control unit.
SKIB3382E