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AT-212
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
7. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-241, "
Control Valve With TCM and A/T Fluid Temperature Sensor 2" .
2. Check A/T fluid condition. Refer to AT- 5 8 , "
Fluid Condition
Check" .
OK or NG
OK >> GO TO 8.
NG >> GO TO 11.
8. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.12).
OK or NG
OK >> GO TO 9.
NG >> Repair or replace damaged parts.
9. CHECK SYMPTOM
Check again. Refer to AT-63, "
Cruise Test - Part 1" , AT-65, "Cruise Test - Part 2" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 10.
10. PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT- 9 0 , "
TCM Input/Output Signal Reference Val-
ues" .
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
11 . DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.12).
OK or NG
OK >> GO TO 9.
NG >> Repair or replace damaged parts.
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AT-214
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
5. DETECT MALFUNCTIONING ITEM
1. Check control valve with TCM. Refer to AT- 2 4 1 , "
Control Valve With TCM and A/T Fluid Temperature Sen-
sor 2" .
2. Disassemble A/T. Refer to AT-273, "
Disassembly" .
3. Check the following items:
–Oil pump assembly. Refer to AT-290, "Oil Pump" .
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
6. DETECT MALFUNCTIONING ITEM
1. Check control valve with TCM. Refer to AT- 2 4 1 , "
Control Valve With TCM and A/T Fluid Temperature Sen-
sor 2" .
2. Disassemble A/T. Refer to AT-273, "
Disassembly" .
3. Check the following items:
–Oil pump assembly. Refer to AT-290, "Oil Pump" .
–Power train system. Refer to AT-273, "Disassembly" .
–Transmission case. Refer to AT-273, "Disassembly" .
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-241, "
Control Valve With TCM and A/T Fluid Temperature Sensor 2" .
2. Check A/T fluid condition. Refer to AT- 5 8 , "
Fluid Condition
Check" .
OK or NG
OK >> GO TO 8.
NG >> GO TO 11.
8. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.13).
OK or NG
OK >> GO TO 9.
NG >> Repair or replace damaged parts.
9. CHECK SYMPTOM
Check again. Refer to AT-63, "
Cruise Test - Part 1" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 10.
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AT-218
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
2. CHECK A/T FLUID LEVEL
Check A/T fluid level. Refer to AT-13, "
Checking A/T Fluid" .
OK or NG
OK >> GO TO 3.
NG >> Refill ATF.
3. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-241, "
Control Valve With TCM and A/T Fluid Temperature Sensor 2" .
2. Check A/T fluid condition. Refer to AT- 5 8 , "
Fluid Condition
Check" .
OK or NG
OK >> GO TO 4.
NG >> GO TO 7.
4. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.25).
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
5. CHECK SYMPTOM
Check again. Refer to AT-63, "
Cruise Test - Part 1" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 6.
6. PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT- 9 0 , "
TCM Input/Output Signal Reference Val-
ues" .
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
SAT6 3 8A
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TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-223
D
E
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MA
B
AT
Revision: August 20072004 QX56
4. CHECK CONTROL CABLE
Check the control cable.
Refer to AT- 2 3 4 , "Checking of A/T Position" .
OK or NG
OK >> GO TO 5.
NG >> Adjust control cable. Refer to AT-234, "
Adjustment of A/
T Position" .
5. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-241, "
Control Valve With TCM and A/T Fluid Temperature Sensor 2" .
2. Check A/T fluid condition. Refer to AT- 5 8 , "
Fluid Condition
Check" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.14).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7. CHECK SYMPTOM
Check again. Refer to AT- 6 6 , "
Cruise Test - Part 3" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8. PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-90, "
TCM Input/Output Signal Reference Val-
ues" .
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
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TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-225
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
4. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-241, "
Control Valve With TCM and A/T Fluid Temperature Sensor 2" .
2. Check A/T fluid condition. Refer to AT- 5 8 , "
Fluid Condition
Check" .
OK or NG
OK >> GO TO 5.
NG >> GO TO 8.
5. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.15).
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6. CHECK SYMPTOM
Check again. Refer to AT- 6 6 , "
Cruise Test - Part 3" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 7.
7. PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-90, "
TCM Input/Output Signal Reference Val-
ues" .
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
8. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.15).
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
A/T Does Not Shift: 3rd gear → 2nd gearUCS002J0
SYMPTOM:
When shifted from 33 to 22 position, does not downshift from 3rd to 2nd gears.
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TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-229
D
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H
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J
K
L
MA
B
AT
Revision: August 20072004 QX56
4. CHECK CONTROL CABLE
Check the control cable.
Refer to AT- 2 3 4 , "Checking of A/T Position" .
OK or NG
OK >> GO TO 5.
NG >> Adjust control cable. Refer to AT-234, "
Adjustment of A/
T Position" .
5. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-241, "
Control Valve With TCM and A/T Fluid Temperature Sensor 2" .
2. Check A/T fluid condition. Refer to AT- 5 8 , "
Fluid Condition
Check" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.17).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7. CHECK SYMPTOM
Check again. Refer to AT- 6 6 , "
Cruise Test - Part 3" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8. PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-90, "
TCM Input/Output Signal Reference Val-
ues" .
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
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TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-231
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B
AT
Revision: August 20072004 QX56
3. CHECK A/T FLUID LEVEL
Check the A/T fluid level again. Refer to AT-13, "
Checking A/T Fluid"
.
OK or NG
OK >> GO TO 4.
NG >> Refill ATF.
4. CHECK CONTROL CABLE
Check the control cable.
Refer to AT- 2 3 4 , "Checking of A/T Position" .
OK or NG
OK >> GO TO 5.
NG >> Adjust control cable. Refer to AT-234, "
Adjustment of A/
T Position" .
5. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-241, "
Control Valve With TCM and A/T Fluid Temperature Sensor 2" .
2. Check A/T fluid condition. Refer to AT- 5 8 , "
Fluid Condition
Check" .
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6. DETECT MALFUNCTIONING ITEM
Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.53).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7. CHECK SYMPTOM
Check again. Refer to AT- 6 6 , "
Cruise Test - Part 3" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
SAT6 3 8A
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![INFINITI QX56 2004 Factory Service Manual EC-110Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
HO2S2 HTR (B1)
[ON/OFF]Indicates [ON/OFF] condition of heated oxy-
gen sensor 2 heater determined by ECM
according to the input signals. HO2S INFINITI QX56 2004 Factory Service Manual EC-110Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
HO2S2 HTR (B1)
[ON/OFF]Indicates [ON/OFF] condition of heated oxy-
gen sensor 2 heater determined by ECM
according to the input signals. HO2S](/manual-img/42/57034/w960_57034-1300.png)
EC-110Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
HO2S2 HTR (B1)
[ON/OFF]Indicates [ON/OFF] condition of heated oxy-
gen sensor 2 heater determined by ECM
according to the input signals. HO2S2 HTR (B2)
[ON/OFF]
I/P PULLY SPD
[rpm]
Indicates the engine speed computed from the
turbine revolution sensor signal.
VEHICLE SPEED
[km/h] or [MPH]
Indicates the vehicle speed computed from
the revolution sensor signal.
IDL A/V LEARN
[YET/CMPLT]
Display the condition of idle air volume learn-
ing
YET: Idle air volume learning has not been
performed yet.
CMPLT: Idle air volume learning has already
been performed successfully.
TRVL AFTER MIL
[km] or [mile]
Distance traveled while MIL is activated.
A/F S1 HTR (B1)
[%]
Indicates A/F sensor 1 heater control value
computed by the ECM according to the input
signals.
The current flow to the heater becomes larger
as the value increases. A/F S1 HTR (B2)
[%]
AC PRESS SEN
[V]
The signal voltage from the refrigerant pres-
sure sensor is displayed.
VHCL SPEED SE
[km/h] or [mph]
The vehicle speed computed from the vehicle
speed signal sent from TCM is displayed.
SET VHCL SPD
[km/h] or [mph]
The preset vehicle speed is displayed.
MAIN SW
[ON/OFF]
Indicates [ON/OFF] condition from ON/
OFF(MAIN) switch signal.
CANCEL SW
[ON/OFF]
Indicates [ON/OFF] condition from CANCEL
switch signal.
RESUME/ACC SW
[ON/OFF]
Indicates [ON/OFF] condition from ACCEL/
RESUME switch signal.
SET SW
[ON/OFF]
Indicates [ON/OFF] condition from COAST/
SET switch signal.
DIST SW
[ON/OFF]
Indicates [ON/OFF] condition from DISTANCE
switch signal.
BRAKE SW1 SW
[ON/OFF]
Indicates [ON/OFF] condition from ASCD
brake switch signal.
BRAKE SW2 SW
[ON/OFF]
Indicates [ON/OFF] condition of stop lamp
switch signal.
VHCL SPD CUT
[NON/CUT]
Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed increased to excessively
high compared with the ASCD set speed, and
ASCD operation is cut off.
LOW SPEED CUT
[NON/CUT]
Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed decreased to excessively
low compared with the ASCD set speed, and
ASCD operation is cut off. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks