speed sensor INFINITI QX56 2004 Factory User Guide

AT-2Revision: August 20072004 QX56 CONSULT-II Reference Value ..............................109
On Board Diagnosis Logic ....................................109
Possible Cause .....................................................109
DTC Confirmation Procedure ...............................109
Diagnostic Procedure ...........................................110
DTC P0720 VEHICLE SPEED SENSOR A/T (REV-
OLUTION SENSOR) ...............................................112
Description ............................................................112
CONSULT-II Reference Value ..............................112
On Board Diagnosis Logic ....................................112
Possible Cause .....................................................112
DTC Confirmation Procedure ...............................112
Diagnostic Procedure ...........................................113
DTC P0725 ENGINE SPEED SIGNAL ...................115
Description ............................................................115
CONSULT-II Reference Value ..............................115
On Board Diagnosis Logic ....................................115
Possible Cause .....................................................115
DTC Confirmation Procedure ...............................115
Diagnostic Procedure ...........................................115
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE .................................................118
Description ............................................................118
CONSULT-II Reference Value ..............................118
On Board Diagnosis Logic ....................................118
Possible Cause .....................................................118
DTC Confirmation Procedure ...............................118
Diagnostic Procedure ...........................................119
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP) .121
Description ............................................................121
CONSULT-II Reference Value ..............................121
On Board Diagnosis Logic ....................................121
Possible Cause .....................................................121
DTC Confirmation Procedure ...............................121
Diagnostic Procedure ...........................................122
DTC P0745 LINE PRESSURE SOLENOID VALVE .124
Description ............................................................124
CONSULT-II Reference Value ..............................124
On Board Diagnosis Logic ....................................124
Possible Cause .....................................................124
DTC Confirmation Procedure ...............................124
Diagnostic Procedure ...........................................125
DTC P1702 TRANSMISSION CONTROL MODULE
(RAM) ......................................................................127
Description ............................................................127
On Board Diagnosis Logic ....................................127
Possible Cause .....................................................127
DTC Confirmation Procedure ...............................127
Diagnostic Procedure ...........................................127
DTC P1703 TRANSMISSION CONTROL MODULE
(ROM) ......................................................................128
Description ............................................................128
On Board Diagnosis Logic ....................................128
Possible Cause .....................................................128
DTC Confirmation Procedure ...............................128
Diagnostic Procedure ...........................................128
DTC P1705 THROTTLE POSITION SENSOR .......129
Description ............................................................129
CONSULT-II Reference Value ..............................129On Board Diagnosis Logic .................................... 129
Possible Cause ..................................................... 129
DTC Confirmation Procedure ................................ 129
Diagnostic Procedure ............................................ 129
DTC P1710 A/T FLUID TEMPERATURE SENSOR
CIRCUIT .................................................................. 131
Description ............................................................ 131
CONSULT-II Reference Value ............................... 131
On Board Diagnosis Logic .................................... 131
Possible Cause ..................................................... 131
DTC Confirmation Procedure ................................ 131
Diagnostic Procedure ............................................ 132
Component Inspection .......................................... 133
DTC P1716 TURBINE REVOLUTION SENSOR .... 134
Description ............................................................ 134
CONSULT-II Reference Value ............................... 134
On Board Diagnosis Logic .................................... 134
Possible Cause ..................................................... 134
DTC Confirmation Procedure ................................ 134
Diagnostic Procedure ............................................ 135
DTC P1721 VEHICLE SPEED SENSOR MTR ....... 136
Description ............................................................ 136
CONSULT-II Reference Value ............................... 136
On Board Diagnosis Logic .................................... 136
Possible Cause ..................................................... 136
DTC Confirmation Procedure ................................ 136
Diagnostic Procedure ............................................ 137
DTC P1730 A/T INTERLOCK ................................. 139
Description ............................................................ 139
On Board Diagnosis Logic .................................... 139
Possible Cause ..................................................... 139
DTC Confirmation Procedure ................................ 139
Judgement of A/T Interlock ................................... 140
Diagnostic Procedure ............................................ 140
DTC P1731 A/T 1ST ENGINE BRAKING ............... 142
Description ............................................................ 142
CONSULT-II Reference Value ............................... 142
On Board Diagnosis Logic .................................... 142
Possible Cause ..................................................... 142
DTC Confirmation Procedure ................................ 142
Diagnostic Procedure ............................................ 143
DTC P1752 INPUT CLUTCH SOLENOID VALVE .. 145
Description ............................................................ 145
CONSULT-II Reference Value ............................... 145
On Board Diagnosis Logic .................................... 145
Possible Cause ..................................................... 145
DTC Confirmation Procedure ................................ 145
Diagnostic Procedure ............................................ 146
DTC P1754 INPUT CLUTCH SOLENOID VALVE
FUNCTION .............................................................. 148
Description ............................................................ 148
CONSULT-II Reference Value ............................... 148
On Board Diagnosis Logic .................................... 148
Possible Cause ..................................................... 148
DTC Confirmation Procedure ................................ 148
Diagnostic Procedure ............................................ 149
DTC P1757 FRONT BRAKE SOLENOID VALVE ... 151
Description ............................................................ 151
CONSULT-II Reference Value ............................... 151

AT-4Revision: August 20072004 QX56 A/T Does Not Shift: 2nd gear → 1st gear .............227
Vehicle Does Not Decelerate By Engine Brake ....230
SHIFT CONTROL SYSTEM ....................................233
Control Device Removal and Installation ..............233
Adjustment of A/T Position ...................................234
Checking of A/T Position ......................................234
A/T SHIFT LOCK SYSTEM .....................................236
Description ............................................................236
Shift Lock System Electrical Parts Location .........236
Wiring Diagram — A/T — SHIFT ..........................237
Shift Lock Control Unit Reference Values .............238
Component Inspection ..........................................239
ON-VEHICLE SERVICE ..........................................241
Control Valve With TCM and A/T Fluid Temperature
Sensor 2 ...............................................................241
Rear Oil Seal ........................................................252
AIR BREATHER HOSE ...........................................253
Removal and Installation ......................................253
TRANSMISSION ASSEMBLY ................................255
Removal and Installation (4x2) .............................255
Removal and Installation (4x4) .............................258
OVERHAUL .............................................................261
Components .........................................................261
Oil Channel ...........................................................269
Locations of Adjusting Shims, Needle Bearings,
Thrust Washers and Snap Rings ..........................271
DISASSEMBLY .......................................................273
Disassembly .........................................................273REPAIR FOR COMPONENT PARTS ...................... 290
Oil Pump ............................................................... 290
Front Sun Gear, 3rd One-Way Clutch ................... 292
Front Carrier, Input Clutch, Rear Internal Gear ..... 295
Mid Sun Gear, Rear Sun Gear, High and Low
Reverse Clutch Hub .............................................. 300
High and Low Reverse Clutch .............................. 305
Direct Clutch ......................................................... 307
ASSEMBLY ............................................................. 309
Assembly (1) ......................................................... 309
Adjustment ............................................................ 322
Assembly (2) ......................................................... 324
SERVICE DATA AND SPECIFICATIONS (SDS) .... 331
General Specifications .......................................... 331
Vehicle Speed When Shifting Gears ..................... 331
Vehicle Speed When Performing and Releasing
Complete Lock-up ................................................. 332
Vehicle Speed When Performing and Releasing
Slip Lock-up .......................................................... 332
Stall Speed ............................................................ 332
Line Pressure ........................................................ 332
A/T Fluid Temperature Sensor .............................. 332
Turbine Revolution Sensor .................................... 332
Vehicle Speed Sensor A/T (Revolution Sensor) ... 332
Reverse brake ....................................................... 333
Total End Play ....................................................... 333

A/T CONTROL SYSTEM
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TCM FunctionUCS002CE
The function of the TCM is to:

Receive input signals sent from various switches and sensors.

Determine required line pressure, shifting point, lock-up operation, and engine brake operation.

Send required output signals to the respective solenoids.
CONTROL SYSTEM OUTLINE
The automatic transmission senses vehicle operating conditions through various sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
CONTROL SYSTEM DIAGRAM
SENSORS (or SIGNALS)


TCM


ACTUATORS
PNP switch
Accelerator pedal position sensor
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Vehicle speed signal
Stop lamp switch signal
Turbine revolution sensor
1st position switch signal
4th position switch signalShift control
Line pressure control
Lock-up control
Engine brake control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
Duet-EA control
CAN systemInput clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch
solenoid valve
Low coast brake solenoid valve
Torque converter clutch solenoid
valve
Line pressure solenoid valve
A/T CHECK indicator lamp
Sta rte r re lay
Back-up lamp relay
LCIA0317E

AT-32
A/T CONTROL SYSTEM
Revision: August 20072004 QX56
CAN CommunicationUCS002CF
SYSTEM DESCRIPTION
Refer to LAN-5, "CAN Communication Unit" .
Input/Output Signal of TCMUCS002CG
*1: Spare for vehicle speed sensor·A/T (revolution sensor)
*2: Spare for accelerator pedal position signal
*3: If these input and output signals are different, the TCM triggers the fail-safe function.
*4: CAN communicationsControl itemLine
pressure
controlVehicle
speed
controlShift
controlLock-up
controlEngine
brake
controlFail-safe
function
(*3)Self-diag-
nostics
function
InputAccelerator pedal position signal
(*4)XXXXXXX
Vehicle speed sensor A/T
(revolution sensor)XXXX XX
Vehicle speed sensor MTR
(*1) (*4)XXXX X
Closed throttle position signal
(*4)(*2) X (*2) X X (*2) X X
Wide open throttle position signal
(*4)(*2) X (*2) X (*2) X X
Turbine revolution sensor 1 X X X X X
Turbine revolution sensor 2
(for 4th speed only)XX X XX
Engine speed signals
(*4)XX
PNP switch XXXXXXX
A/T fluid temperature sensors 1, 2 X X X X X X X
ICC or
ASCDOperation signal
(*4)XXXX
Overdrive cancel
signal
(*4)XXX
TCM power supply voltage signal X X X X X X
Out-
putDirect clutch solenoid (ATF pres-
sure switch 5)XX XX
Input clutch solenoid (ATF pressure
switch 3)XX XX
High and low reverse clutch sole-
noid (ATF pressure switch 6)XX XX
Front brake solenoid (ATF pressure
switch 1)XX XX
Low coast brake solenoid (ATF
pressure switch 2)XX XXX
Line pressure solenoid X X X X X X X
TCC solenoid X X X
Starte r re la yXX

AT-34
A/T CONTROL SYSTEM
Revision: August 20072004 QX56
During Shift Change
The necessary and adequate line pressure for shift change is set.
For this reason, line pressure pattern setting corresponds to input
torque and gearshift selection. Also, line pressure characteristic is
set according to engine speed, during engine brake operation.
At Low Fluid Temperature
When the A/T fluid temperature drops below the prescribed tempera-
ture, in order to speed up the action of each friction element, the line
pressure is set higher than the normal line pressure characteristic.
Shift ControlUCS002CI
The clutch pressure control solenoid is controlled by the signals from the switches and sensors. Thus, the
clutch pressure is adjusted to be appropriate to the engine load state and vehicle driving state. It becomes
possible to finely control the clutch hydraulic pressure with high precision and a smoother shift change charac-
teristic is attained.
SHIFT CHANGE
The clutch is controlled with the optimum timing and oil pressure by the engine speed, engine torque informa-
tion, etc.
PCIA0010E
PCIA0 011 E
PCIA0012E

TROUBLE DIAGNOSIS
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TROUBLE DIAGNOSISPFP:00004
DTC Inspection Priority ChartUCS002C R
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
If DTC U1000 is displayed with other DTCs, first perform the trouble diagnosis for DTC U1000. Refer to
AT-1 03
.
Fail-SafeUCS002CS
The TCM has an electrical fail-safe mode. This mode makes it possible to operate even if there is a an error in
a main electronic control input/output signal circuit. In fail-safe mode the transmission is fixed in 2nd or 4th
(depending on the breakdown position), so the customer should feel “slipping” or “poor acceleration”. When
fail-safe mode is triggered, when the ignition switch is switched “ON”, the AT CHECK indicator lamp flashes for
about 8 seconds.
Even when the electronic circuits are normal, under special conditions (for example, when slamming on the
brake with the wheels spinning drastically and stopping the tire rotation), the transmission can go into fail-safe
mode. If this happens, switch “OFF” the ignition switch for 10 seconds, then switch it “ON” again to return to
the normal shift pattern. Also, the AT CHECK indicator lamp flashes for about 8 seconds once, then is cleared.
Therefore, the customer's vehicle has returned to normal, so handle according to the “diagnostics flow” (Refer
to AT-46, "
WORK FLOW" ).
FAI L-S AFE FUN CT ION
If any malfunction occurs in a sensor or solenoid, this function controls the A/T to mark driving possible.
Vehicle Speed Sensor

Signals are input from two systems - from vehicle speed sensor A/T (revolution sensor) installed on the
transmission and from combination meter so normal driving is possible even if there is a malfunction in
one of the systems. And if vehicle speed sensor A/T (revolution sensor) has unusual cases, 5th gear is
prohibited.
Accelerator Pedal Position Sensor

If there is a malfunction in one of the systems, the accelerator opening angle is controlled by ECM accord-
ing to a pre-determined accelerator angle to make driving possible. And if there are malfunctions in tow
systems, the engine speed is fixed by ECM to a pre-determined engine speed to make driving possible.
Throttle Position Sensor

If there is a malfunction in one of the systems, the accelerator opening angle is controlled by ECM accord-
ing to a pre-determined accelerator angle to make driving possible. And if there are malfunctions in tow
systems, the accelerator opening angle is controlled by the idle signal sent from the ECM which is based
on input indicating either idle condition or off-idle condition (pre-determined accelerator opening) in order
to make driving possible.
PNP Switch

In the unlikely event that a malfunction signal enters the TCM, the position indicator is switched “OFF”, the
starter relay is switched “OFF” (starter starting is disabled), the back-up lamp relay switched “OFF” (back-
up lamp is OFF) and the position is fixed to the “D” range to make driving possible.
Starter Relay

The starter relay is switched “OFF”. (Starter starting is disabled.)
Priority Detected items (DTC)
1 U1000 CAN communication line
2 Except above

TROUBLE DIAGNOSIS
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How To Perform Trouble Diagnosis For Quick and Accurate RepairUCS002CT
INTRODUCTION
The TCM receives a signal from the vehicle speed sensor, accelerator pedal position sensor (throttle position
sensor) or PNP switch and provides shift control or lock-up control via A/T solenoid valves.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used with the OBD-related parts of the
A/T system for malfunction-diagnostic purposes. The TCM is capa-
ble of diagnosing malfunctioning parts while the ECM can store mal-
functions in its memory.
Input and output signals must always be correct and stable in the
operation of the A/T system. The A/T system must be in good oper-
ating condition and be free of valve seizure, solenoid valve malfunc-
tion, etc.
It is much more difficult to diagnose a error that occurs intermittently
rather than continuously. Most intermittent errors are caused by poor
electric connections or improper wiring. In this case, careful check-
ing of suspected circuits may help prevent the replacement of good
parts.
A visual check only may not find the cause of the errors. A road test
with CONSULT-II (or GST) or a circuit tester connected should be
performed. Follow the AT-46, "
WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such errors, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “Diagnostic Worksheet” as shown on
the example (Refer to AT- 4 7
) should be used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot driveability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
SAT6 3 1IB
SAT6 3 2I
SEF 2 34 G

AT-48
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
4❏ Perform all road tests and enter checks in required inspection items.AT-6 1
4-1.Check before engine is started
AT-6 2
❏ AT-191, "AT CHECK Indicator Lamp Does Not Come On" .
❏ Perform self-diagnostics Enter checks for detected items. AT- 9 3
❏ AT- 1 0 3 , "DTC U1000 CAN COMMUNICATION LINE"
❏ AT- 1 0 5 , "DTC P0615 START SIGNAL CIRCUIT"
❏ AT- 1 0 8 , "DTC P0700 TCM"
❏ AT- 1 0 9 , "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT- 11 2 , "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT- 11 5 , "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT- 11 8 , "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT- 1 2 1 , "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT- 1 2 4 , "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT- 1 2 7 , "DTC P1702 TRANSMISSION CONTROL MODULE (RAM)"
❏ AT- 1 2 8 , "DTC P1703 TRANSMISSION CONTROL MODULE (ROM)"
❏ AT- 1 2 9 , "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT- 1 3 1 , "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT- 1 3 4 , "DTC P1716 TURBINE REVOLUTION SENSOR"
❏ AT- 1 3 6 , "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT- 1 3 9 , "DTC P1730 A/T INTERLOCK"
❏ AT- 1 4 2 , "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT- 1 4 5 , "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT- 1 4 8 , "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT- 1 5 1 , "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT- 1 5 4 , "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT- 1 5 7 , "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT- 1 6 0 , "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT- 1 6 3 , "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT- 1 6 6 , "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT- 1 6 9 , "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT- 1 7 2 , "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT- 1 7 5 , "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT- 1 7 8 , "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT- 1 8 1 , "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT- 1 8 4 , "DTC P1846 ATF PRESSURE SWITCH 6"
4-2.Idle inspection
AT-6 2
❏ AT-192, "Engine Cannot Be Started In “P” or “N” Position"
❏ AT-193, "In “P” Position, Vehicle Moves When Pushed"
❏ AT-194, "In “N” Position, Vehicle Moves"
❏ AT-195, "Large Shock (“N” to “D” Position)"
❏ AT-198, "Vehicle Does Not Creep Backward In “R” Position"
❏ AT-201, "Vehicle Does Not Creep Forward In “D” Position"
4-3.Driving tests
AT-6 3
Part 1
❏ 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"
❏ AT-213, "A/T Does Not Shift: D4 → D5"
❏ AT-215, "A/T Does Not Perform Lock-up"
❏ AT-217, "A/T Does Not Hold Lock-up Condition"
❏ AT-219, "Lock-up Is Not Released"
❏ AT-220, "Engine Speed Does Not Return to Idle"

TROUBLE DIAGNOSIS
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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

TROUBLE DIAGNOSIS
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Judgement of Line Pressure Test
ROAD TEST
Description

The road test inspects overall performance of the A/T and analyzes possible malfunction causes.

The road test is carried out in the following three stages.
1. Check before engine is started. Refer to AT - 6 2
.
2. Check at idle. Refer to AT- 6 2
.
3. Cruise test

Inspect all the items from Part 1 to Part 3. Refer to AT- 6 3 , AT- 6 5 , AT- 6 6 .

Before beginning the road test, check the test procedure and inspection items.

Test all inspection items until the symptom is uncovered. Diagnose NG items when all road tests are com-
plete.
Judgement Possible cause
Idle speedLow for all positions
(P, R, N, D)Possible causes include malfunctions in the pressure supply system and low oil pump output.
For example

Oil pump wear

Pressure regulator valve or plug sticking or spring fatigue

Oil strainer
oil pump
pressure regulator valve passage oil leak

Engine idle speed too low
Only low for a spe-
cific positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.
HighPossible causes include a sensor malfunction or malfunction in the line pressure adjustment func-
tion.
For example

Accelerator pedal position signal malfunction

ATF temperature sensor malfunction

Line pressure solenoid malfunction (sticking in “OFF” state, filter clog, cut line)

Pressure regulator valve or plug sticking
Stall speedOil pressure does
not rise higher than
the oil pressure for
idle.Possible causes include a sensor malfunction or malfunction in the pressure adjustment function.
For example

Accelerator pedal position signal malfunction

TCM breakdown

Line pressure solenoid malfunction (shorting, sticking in“ ON” state)

Pressure regulator valve or plug sticking

Pilot valve sticking or pilot filter clogged
The pressure rises,
but does not enter
the standard posi-
tion.Possible causes include malfunctions in the pressure supply system and malfunction in the pres-
sure adjustment function.
For example

Accelerator pedal position signal malfunction

Line pressure solenoid malfunction (sticking, filter clog)

Pressure regulator valve or plug sticking

Pilot valve sticking or pilot filter clogged
Only low for a spe-
cific positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.