INFINITI QX56 2004 Factory Service Manual

AT-50
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
A/T Electrical Parts LocationUCS002CU
BCIA0028E

TROUBLE DIAGNOSIS
AT-51
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
Circuit DiagramUCS002CV
WCWA0216E

AT-52
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Wiring Diagram — AT —UCS002CW
BCWA0157E

TROUBLE DIAGNOSIS
AT-53
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
BCWA0055E

AT-54
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
WCWA0217E

TROUBLE DIAGNOSIS
AT-55
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
WCWA0218E

AT-56
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
BCWA0155E

TROUBLE DIAGNOSIS
AT-57
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
TCM TERMINAL MEASUREMENT CHART
TCM terminals and data are reference value. Measured between each terminal and ground.
Te r m i n a l
No.Wire
colorItem Condition Data (Approx.)
1PPower supply
(Memory back-up)– Battery voltage
2PPower supply
(Memory back-up)– Battery voltage
3 W CAN-H – –
4VK-line (CONSULT-
II signal)The terminal is connected to the data link connector for CONSULT-II. –
5 B Ground – –
6Y/RPower supply– Battery voltage
–0V
7RBack-up lamp
relaySelector lever in “R” position. 0V
Selector lever in other positions. Battery voltage
8 R CAN-L – –
9 B/R Starter relaySelector lever in “N”,“ P” positions. Battery voltage
Selector lever in other positions. 0V
10 B Ground – –

AT-58
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Inspections Before Trouble DiagnosisUCS002CX
A/T FLUID CHECK
Fluid Leakage and Fluid Level Check

Inspect for fluid leakage and check the fluid level. Refer to AT - 1 3 , "Checking A/T Fluid" .
Fluid Condition Check
Inspect the fluid condition.
STALL TEST
Stall Test Procedure
1. Inspect the amount of engine oil. Replenish the engine oil if necessary.
2. Drive for about 10 minutes to warm up the vehicle so that the A/
T fluid temperature is 50 to 80°C (122 to 176°F). Inspect the
amount of ATF. Replenish if necessary.
3. Securely engage the parking brake so that the tires do not turn.
4. Engine start, apply foot brake, and place selector lever in “D”
position.
5. While holding down the foot brake, gradually press down the
accelerator pedal.
6. Quickly read off the stall speed, then quickly remove your foot
from the accelerator pedal.
CAUTION:
Do not hold down the accelerator pedal for more than 5 sec-
onds during this test.
7. Move the selector lever to the “N” position.
8. Cool down the ATF.
Fluid condition Conceivable Cause Required Operation
Varnished (viscous
varnish state)Clutch, brake
scorchedReplace the ATF and check the A/T
main unit and the vehicle for mal-
functions (wire harnesses, cooler
pipes, etc.)
Milky white or
cloudyWater in the fluidReplace the ATF and check for
places where water is getting in.
Large amount of
metal powder mixed
inUnusual wear of
sliding parts within
A/TReplace the ATF and check for
improper operation of the A/T.
SAT6 3 8A
SAT6 4 7B
SCIA1224E
SAT5 1 4G

TROUBLE DIAGNOSIS
AT-59
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
CAUTION:
Run the engine at idle for at least one minute.
Judgement of Stall Test
O: Stall speed within standard value position
H: Stall speed higher than standard value
L: Stall speed lower than standard value
Stall test standard value position
LINE PRESSURE TEST
Line Pressure Test Port
Line Pressure Test Procedure
1. Inspect the amount of engine oil and replenish if necessary.
2. Drive the car for about 10 minutes to warm it up so that the ATF reaches in range of 50 to 80°C (122 to
176°F), then inspect the amount of ATF and replenish if necessary.
NOTE:
The automatic fluid temperature rises in range of 50 to 80°C (122 to 176°F) during 10 minutes of
driving.Stall speed: 2,500 - 2,800 rpm
Selector lever position
Expected problem location
DR
Stall rotation HO

Forward brake

Forward one-way clutch

1st one-way clutch

3rd one-way clutch
OH

Reverse brake
LL

Engine and torque converter one-way clutch
HH

Line pressure low
Does not shift-up D position 1 → 2 Slipping in 2nd, 3rd, 4th gears Direct clutch slippage
Does not shift-up D position 2 → 3 Slipping in 3rd, 4th, 5th gears High & low reverse clutch slippage
Does not shift-up D position 3 → 4 Slipping in 4th, 5th gears Input clutch slippage
Does not shift-up D position 4 → 5 Slipping in 5th gear Front brake slippage
SCIA1291E