2004 INFINITI QX56 Can communication

TROUBLE DIAGNOSIS
AT-49
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
44-3Part 2
AT- 6 5
❏ AT-203, "Vehicle Cannot Be Started From D1"
❏ AT-206, "A/T Does Not Shift: D1 → D2"
❏ AT-208, "A/T Does Not Shift: D2 → D3"
❏ AT-210, "A/T Does Not Shift: D3 → D4"
Part 3
AT- 6 6
❏ AT-221, "A/T Does Not Shift: 5th gear → 4th gear"
❏ AT-224, "A/T Does Not Shift: 4th gear → 3rd gear"
❏ AT-225, "A/T Does Not Shift: 3rd gear → 2nd gear"
❏ AT-227, "A/T Does Not Shift: 2nd gear → 1st gear"
❏ AT-230, "Vehicle Does Not Decelerate By Engine Brake"
❏ Perform self-diagnostics Enter checks for detected items. AT- 9 3
❏ AT-103, "DTC U1000 CAN COMMUNICATION LINE"
❏ AT-105, "DTC P0615 START SIGNAL CIRCUIT"
❏ AT-108, "DTC P0700 TCM"
❏ AT-109, "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT-112, "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT-115, "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT-118, "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT-121, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT-124, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT-127, "DTC P1702 TRANSMISSION CONTROL MODULE (RAM)"
❏ AT-128, "DTC P1703 TRANSMISSION CONTROL MODULE (ROM)"
❏ AT-129, "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT-131, "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT-134, "DTC P1716 TURBINE REVOLUTION SENSOR"
❏ AT-136, "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT-139, "DTC P1730 A/T INTERLOCK"
❏ AT-142, "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT-145, "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT-148, "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-151, "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT-154, "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT-157, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT-160, "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-163, "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT-166, "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT-169, "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT-172, "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT-175, "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT-178, "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT-181, "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT-184, "DTC P1846 ATF PRESSURE SWITCH 6"
5❏ Inspect each system for items found to be NG in the self-diagnostics and repair or replace the malfunction
parts.
6❏ Perform all road tests and enter the checks again for the required items.AT- 6 1
7❏ For any remaining NG items, perform the “diagnostics procedure” and repair or replace the malfunction parts.
See the chart for diagnostics by symptoms. (This chart also contains other symptoms and inspection proce-
dures.)AT- 6 8
8❏ Erase the results of the self-diagnostics from the TCM.AT- 4 0

AT-68
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Symptom ChartUCS002D6

The diagnostics item numbers show the sequence for inspection. Inspect in order from item 1.

Overhaul and inspect inside the A/T only if A/T fluid condition is NG. Refer to AT-58, "Fluid Condi-
tion Check" .
No. Items Symptom Condition Diagnostic ItemReference
page
1
Shift
ShockLarge shock. (“N” →“
D” position)
Refer to AT-195,
"Large Shock (“N” to
“D” Position)" .ON vehicle1. Engine idle speedEC-32
2. Engine speed signalAT - 11 5
3. Accelerator pedal position sensorAT- 1 2 9
4. Control cable adjustmentAT- 2 3 4
5. ATF temperature sensorAT- 1 3 1
6. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1
7. CAN communication lineAT- 1 0 3
8. Fluid level and stateAT-5 8
9. Line pressure testAT-5 9
10. Control valve with TCMAT- 2 4 2
OFF vehicle11. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 8 , AT- 1 9
.)AT- 2 7 3
2Shock is too large
when changing D1 →
D
2 .ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
4. CAN communication lineAT- 1 0 3
5. Engine speed signalAT - 11 5
6. Turbine revolution sensorAT- 1 3 4
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
8. Fluid level and stateAT-5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle 10. Direct clutchAT- 3 0 7
3Shock is too large
when changing D2 →
D
3 .ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. ATF pressure switch 6, high and low reverse clutch sole-
noid valveAT- 1 8 4,
AT- 1 6 3
4. CAN communication lineAT- 1 0 3
5. Engine speed signalAT - 11 5
6. Turbine revolution sensorAT- 1 3 4
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
8. Fluid level and stateAT-5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle 10. High and low reverse clutchAT- 3 0 5

TROUBLE DIAGNOSIS
AT-69
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
4
Shift
ShockShock is too large
when changing D3 →
D
4 .ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. ATF pressure switch 3 and input clutch solenoid valveAT- 1 7 8,
AT- 1 4 5
4. CAN communication lineAT- 1 0 3
5. Engine speed signalAT- 11 5
6. Turbine revolution sensorAT- 1 3 4
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
8. Fluid level and stateAT- 5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle 10. Input clutchAT- 2 9 5
5Shock is too large
when changing D4 →
D
5 .ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1

4. CAN communication lineAT- 1 0 3
5. Engine speed signalAT- 11 5
6. Turbine revolution sensorAT- 1 3 4
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
8. Fluid level and stateAT- 5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle10. Front brake (brake band)AT- 2 6 111. Input clutchAT- 2 9 5
6Shock is too large for
downshift when accel-
erator pedal is
pressed.ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. CAN communication lineAT- 1 0 3
4. Engine speed signalAT- 11 5
5. Turbine revolution sensorAT- 1 3 4
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
7. Fluid level and stateAT- 5 8
8. Control valve with TCMAT- 2 4 1
OFF vehicle9. Front brake (brake band)AT- 2 6 110. Input clutchAT- 2 9 5
11. High and low reverse clutchAT- 3 0 5
12. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
page

AT-70
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
7
Shift
ShockShock is too large for
upshift when acceler-
ator pedal is released.ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. Engine speed signalAT - 11 5
4. CAN communication lineAT- 1 0 3
5. Turbine revolution sensorAT- 1 3 4
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
7. Fluid level and stateAT-5 8
8. Control valve with TCMAT- 2 4 1
OFF vehicle9. Front brake (brake band)AT- 2 6 110. Input clutchAT- 2 9 5
11. High and low reverse clutchAT- 3 0 5
12. Direct clutchAT- 3 0 7
8Shock is too large for
lock-up.ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. Engine speed signalAT - 11 5
4. CAN communication lineAT- 1 0 3
5. Turbine revolution sensorAT- 1 3 4
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
7. Torque converter clutch solenoid valveAT - 11 8
8. Fluid level and stateAT-5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle 10. Torque converterAT- 2 7 3
9Shock is too large
during engine brake.ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. CAN communication lineAT- 1 0 3
4. Fluid level and stateAT-5 8
5. Control valve with TCMAT- 2 4 1
OFF vehicle6. Front brake (brake band)AT- 2 6 17. Input clutchAT- 2 9 5
8. High and low reverse clutchAT- 3 0 5
9. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-71
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX5610
No Up
ShiftGear does not change
from D
1 → D2 .
Refer to AT- 2 0 6 , "
A/T
Does Not Shift: D1 →
D2" .ON vehicle1. Fluid level and stateAT- 5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
4. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle 7. Direct clutchAT- 3 0 7
11Gear does not change
from D2 → D3 .
Refer toAT- 2 0 8 , "
A/T
Does Not Shift: D2 →
D3" .ON vehicle1. Fluid level and stateAT- 5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 6, high and low reverse clutch sole-
noid valveAT- 1 8 4,
AT- 1 6 3
4. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle 7. High and low reverse clutchAT- 3 0 5
12Gear does not change
from D
3 → D4 .
Refer toAT- 2 1 0 , "
A/T
Does Not Shift: D3 →
D4" .ON vehicle1. Fluid level and stateAT- 5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 3 and input clutch solenoid valveAT- 1 7 8,
AT- 1 4 5
4. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1
5. Line pressure testAT- 5 9
6. CAN communication lineAT- 1 0 3
7. Control valve with TCMAT- 2 4 1
OFF vehicle 8. Input clutchAT- 2 9 5
13Gear does not change
from D
4 → D5 .
Refer toAT- 2 1 3 , "
A/T
Does Not Shift: D4 →
D5" .ON vehicle1. Fluid level and stateAT- 5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
5. Turbine revolution sensorAT- 1 3 4
6. Line pressure testAT- 5 9
7. CAN communication lineAT- 1 0 3
8. Control valve with TCMAT- 2 4 1
OFF vehicle9. Front brake (brake band)AT- 2 7 310. Input clutchAT- 2 9 5
No. Items Symptom Condition Diagnostic ItemReference
page

AT-72
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
14
No Down
ShiftIn “D” range, does not
downshift to 4th gear.
Refer to AT-221, "A/T
Does Not Shift: 5th
gear → 4th gear" .ON vehicle1. Fluid level and stateAT-5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6

3. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5
,
AT- 1 5 1
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
5. CAN communication lineAT- 1 0 3
6. Line pressure testAT-5 9
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Front brake (brake band)AT- 2 7 39. Input clutchAT- 2 9 5
15In “D” range, does not
downshift to 3rd gear.
Refer toAT- 2 2 4 , "A/T
Does Not Shift: 4th
gear → 3rd gear" .ON vehicle1. Fluid level and stateAT-5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 3 and input clutch solenoid valveAT- 1 7 8,
AT- 1 4 5
4. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1
5. CAN communication lineAT- 1 0 3
6. Line pressure testAT-5 9
7. Control valve with TCMAT- 2 4 1
OFF vehicle 8. Input clutchAT- 2 9 5
16In “D” range, does not
downshift to 2nd gear.
Refer toAT- 2 2 5 , "A/T
Does Not Shift: 3rd
gear → 2nd gear" .ON vehicle1. Fluid level and stateAT-5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6

3. ATF pressure switch 6, high and low reverse clutch sole-
noid valveAT- 1 8 4
,
AT- 1 6 3
4. CAN communication lineAT- 1 0 3
5. Line pressure testAT-5 9
6. Control valve with TCMAT- 2 4 1
OFF vehicle 7. High and low reverse clutchAT- 3 0 5
17In “D” range, does not
downshift to 1st gear.
Refer toAT- 2 2 7 , "A/T
Does Not Shift: 2nd
gear → 1st gear" .ON vehicle1. Fluid level and stateAT-5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
4. CAN communication lineAT- 1 0 3
5. Line pressure testAT-5 9
6. Control valve with TCMAT- 2 4 1
OFF vehicle 7. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-73
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
18
Slips/Will
Not
engageWhen “D” position,
remains in 1st gear.ON vehicle1. Fluid level and stateAT- 5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. Direct clutch solenoid valveAT- 1 5 7
4. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. 3rd one-way clutchAT- 2 9 2
8. 1st one-way clutchAT- 3 0 0
9. Gear systemAT- 2 6 1
10. Reverse brakeAT- 2 7 3
11. Forward one-way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to
AT- 1 8
, AT-1 9 .)AT- 2 7 3
12. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT-1 8
, AT - 1 9
.)AT- 2 7 3
19When “D” position,
remains in 2nd gear.ON vehicle1. Fluid level and stateAT- 5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTR AT- 11 2 ,
AT- 1 3 6
3. Low coast brake solenoid valveAT- 1 6 9
4. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. 3rd one-way clutchAT- 2 9 2
8. Gear systemAT- 2 6 1
9. Direct clutchAT- 3 0 7
10. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT-1 8
, AT - 1 9
.)AT- 2 7 3
No. Items Symptom Condition Diagnostic ItemReference
page

AT-74
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
20
Slips/Will
Not
engageWhen “D” position,
remains in 3rd gear.ON vehicle1. Fluid level and stateAT-5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. Line pressure testAT-5 9
4. CAN communication lineAT- 1 0 3
5. Control valve with TCMAT- 2 4 1
OFF vehicle6. 3rd one-way clutchAT- 2 9 2
7. Gear systemAT- 2 6 1
8. High and low reverse clutchAT- 3 0 5
9. Forward one-way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to
AT-1 8
, AT- 1 9 .)AT- 2 7 3
10. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 8
, AT- 1 9
.)AT- 2 7 3
21When “D” position,
remains in 4th gear.ON vehicle1. Fluid level and stateAT-5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 3 and input clutch solenoid valveAT- 1 7 8,
AT- 1 4 5
4. ATF pressure switch 5 and direct clutch solenoid valveAT-181,AT-
157
5. ATF pressure switch 6, high and low reverse clutch sole-
noid valveAT- 1 8 4
,
AT- 1 6 3
6. Low coast brake solenoid valveAT- 1 6 9
7. Front brake solenoid valveAT- 1 5 1
8. Line pressure testAT-5 9
9. CAN communication lineAT- 1 0 3
10. Control valve with TCMAT- 2 4 1
OFF vehicle11. Input clutchAT- 2 9 512. Gear systemAT- 2 6 1
13. High and low reverse clutchAT- 3 0 5
14. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
page