AT-30
A/T CONTROL SYSTEM
Revision: 2004 November 2004 FX35/FX45
TCM FunctionACS002LF
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
Manual mode switch signal
Stop lamp switch signal
Turbine revolution sensor
ATF pressure switchShift 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
Starter relay
Back-up lamp relay
SCIA5325E
AT-38
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Revision: 2004 November 2004 FX35/FX45
ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
IntroductionACS002LN
The A/T system has two self-diagnostic systems.
The first is the emission-related on board diagnostic system (OBD-II) performed by the TCM in combination
with the ECM. The malfunction is indicated by the MIL (malfunction indicator lamp) and is stored as a DTC in
the ECM memory but not the TCM memory.
The second is the TCM original self-diagnosis indicated by the A/T CHECK indicator lamp. The malfunction is
stored in the TCM memory. The detected items are overlapped with OBD-II self-diagnostic items. For detail,
refer to AT- 9 4 , "
Display Items List" .
OBD-II Function for A/T SystemACS002LO
The ECM provides emission-related on board diagnostic (OBD-II) functions for the A/T system. One function
is to receive a signal from the TCM used with OBD-related parts of the A/T system. The signal is sent to the
ECM when a malfunction occurs in the corresponding OBD-related part. The other function is to indicate a
diagnostic result by means of the MIL (malfunction indicator lamp) on the instrument panel. Sensors, switches
and solenoid valves are used as sensing elements.
The MIL automatically illuminates in One or Two Trip Detection Logic when a malfunction is sensed in relation
to A/T system parts.
One or Two Trip Detection Logic of OBD-IIACS002LP
ONE TRIP DETECTION LOGIC
If a malfunction is sensed during the first test drive, the MIL will illuminate and the malfunction will be stored in
the ECM memory as a DTC. The TCM is not provided with such a memory function.
TWO TRIP DETECTION LOGIC
When a malfunction is sensed during the first test drive, it is stored in the ECM memory as a 1st trip DTC
(diagnostic trouble code) or 1st trip freeze frame data. At this point, the MIL will not illuminate. — First Trip
If the same malfunction as that experienced during the first test drive is sensed during the second test drive,
the MIL will illuminate. — Second Trip
The “Trip” in the “One or Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation.
OBD-II Diagnostic Trouble Code (DTC)ACS002LQ
HOW TO READ DTC AND 1ST TRIP DTC
DTC and 1st trip DTC can be read by the following methods.
( with CONSULT-II or GST) CONSULT-II or GST (Generic Scan Tool) Examples: P0705, P0720 etc.
These DTC are prescribed by SAE J2012.
(CONSULT-II also displays the malfunctioning component or system.)
1st trip DTC No. is the same as DTC No.
Output of the diagnostic trouble code indicates that the indicated circuit has a malfunction. How-
ever, in case of the Mode II and GST, they do not indicate whether the malfunction is still occurring
or occurred in the past and returned to normal.
CONSULT-II can identify them as shown below, therefore, CONSULT-II (if available) is recom-
mended.
A sample of CONSULT-II display for DTC and 1st trip DTC is shown
on the next page. DTC or 1st trip DTC of a malfunction is displayed
in SELF-DIAGNOSTIC RESULTS mode for “ENGINE” with CON-
SULT-II. Time data indicates how many times the vehicle was driven
after the last detection of a DTC.
SAT014K
ON BOARD DIAGNOSTIC (OBD) SYSTEM
AT-41
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Revision: 2004 November 2004 FX35/FX45
HOW TO ERASE DTC (NO TOOLS)
The A/T CHECK indicator lamp is located on the instrument panel.
1. If the ignition switch stays “ON” after repair work, be sure to turn ignition switch “OFF” once. Wait at least
10 seconds and then turn it “ON” (engine stopped) again.
2. Perform “TCM SELF-DIAGNOSTIC PROCEDURE (NO TOOLS)”. Refer to AT- 1 0 3 , "
TCM SELF-DIAG-
NOSTIC PROCEDURE (NO TOOLS)" (The engine warm-up step can be skipped when performing the
diagnosis only to erase the DTC.)
3. Perform “OBD-II SELF-DIAGNOSTIC PROCEDURE (NO TOOLS)”. Refer to EC-67, "
How to Erase DTC"
(for VQ35DE) or EC-715, "How to Erase DTC" (for VK45DE).
Malfunction Indicator Lamp (MIL)ACS002LR
DESCRIPTION
The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned “ON” with-
out the engine running. This is a bulb check.
If the MIL does not light up, refer to DI-39, "WARNING
LAMPS" , or see EC-641, "MIL AND DATA LINK CONNEC-
TOR" (for VQ35DE) or EC-1318, "MIL AND DATA LINK
CONNECTOR" (for VK45DE).
2. When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.
SEF217U
AT-42
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
TROUBLE DIAGNOSISPFP:00004
DTC Inspection Priority ChartACS007A2
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 DTC, first perform the trouble diagnosis for “DTC U1000 CAN
COMMUNICATION LINE”. Refer to AT- 1 0 5
.
Fail-SafeACS007A3
The TCM has an electrical fail-safe mode. This mode makes it possible to operate even if there is a an mal-
function in a main electronic control input/output signal circuit.
In fail-safe mode, even if the selector lever is “D” or “M” mode, the transmission is fixed in 2nd or 4th (depend-
ing 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 A/T CHECK indicator lamp flashes for about
8 seconds. (Refer to AT- 1 0 3 , "
TCM SELF-DIAGNOSTIC PROCEDURE (NO TOOLS)" ).
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 A/T 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- 4 5
).
FAIL-SAFE FUNCTION
If any malfunction occurs in a sensor or solenoid, this function controls the A/T to make driving possible.
Vehicle Speed Sensor A/T (Revolution 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 and
manual mode are 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
AT-44
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
How To Perform Trouble Diagnosis For Quick and Accurate RepairACS007A4
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- 4 5 , "
WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a drive ability 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 6
) should be used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot drive ability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
SAT631IB
SAT632I
SEF234G
AT-46
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
DIAGNOSTIC WORKSHEET
Information From Customer
KEY POINTS
WHAT..... Vehicle and A/T model
WHEN..... Date, Frequencies
WHERE..... Road conditions
HOW..... Operating conditions, Symptoms
Diagnostic Worksheet Chart
Customer name MR/MS Model and Year VIN
Trans. Model Engine Mileage
Incident Date Manuf. Date In Service Date
Frequency❏ Continuous❏ Intermittent ( times a day)
Symptoms❏ Vehicle does not move. (❏ Any position❏ Particular position)
❏ No up-shift (❏ 1st → 2nd❏ 2nd → 3rd❏ 3rd → 4th ❏ 4th → 5th)
❏ No down-shift (❏ 5th → 4th ❏ 4th → 3rd❏ 3rd → 2nd❏ 2nd → 1st)
❏ Lock-up malfunction
❏ Shift point too high or too low.
❏ Shift shock or slip (❏ N → D❏ Lock-up❏ Any drive position)
❏ Noise or vibration
❏ No kick down
❏ No pattern select
❏ Others
()
A/T CHECK indicator lamp Blinks for about 8 seconds.
❏ Continuously lit❏ Not lit
Malfunction indicator lamp (MIL)❏ Continuously lit❏ Not lit
1❏ Read the item on “cautions concerning fail-safe and understand the customer's complaint.AT- 4 2
2❏ A/T fluid inspection
AT- 5 1❏ Leak (Repair leak location.)
❏ State
❏ Amount
3❏ Stall test and line pressure test
AT- 5 1
,
AT- 5 2
❏ Stall test
❏ Torque converter one-way clutch
❏ Front brake
❏ High and low reverse clutch
❏ Low coast brake
❏ Forward brake
❏ Reverse brake
❏ Forward one-way clutch❏ 1st one-way clutch
❏ 3rd one-way clutch
❏ Engine
❏ Line pressure low
❏ Except for input clutch and direct
clutch, clutches and brakes OK
❏ Line pressure inspection - Suspected part:
TROUBLE DIAGNOSIS
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Revision: 2004 November 2004 FX35/FX45
4❏ Execute all road tests and enter checks in required inspection items.AT- 5 4
4-1.Check before engine is started
AT- 5 5
❏ The A/T CHECK Indicator Lamp does come on. AT- 1 9 1 .
❏ Perform self-diagnostics. Enter checks for detected items. AT- 9 4
, AT-103
❏ AT-105, "DTC U1000 CAN COMMUNICATION LINE" .
❏ AT-108, "
DTC P0615 START SIGNAL CIRCUIT" .
❏ AT-112, "
DTC P0705 PARK/NEUTRAL POSITION SWITCH" .
❏ AT-116, "
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)" .
❏ AT-121, "
DTC P0725 ENGINE SPEED SIGNAL" .
❏ AT-121, "
DTC P0725 ENGINE SPEED SIGNAL" .
❏ AT-123, "
DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE" .
❏ AT-125, "
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)" .
❏ AT-127, "
DTC P0745 LINE PRESSURE SOLENOID VALVE" .
❏ AT-129, "
DTC P1701 TRANSMISSION CONTROL MODULE (POWER SUPPLY)" .
❏ AT-133, "
DTC P1702 TRANSMISSION CONTROL MODULE (RAM)" .
❏ AT-134, "
DTC P1703 TRANSMISSION CONTROL MODULE (ROM)" .
❏ AT-135, "
DTC P1704 TRANSMISSION CONTROL MODULE (EEPROM)" .
❏ AT-136, "
DTC P1705 THROTTLE POSITION SENSOR" .
❏ AT-139, "
DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT" .
❏ AT-143, "
DTC P1716 TURBINE REVOLUTION SENSOR" .
❏ AT-145, "
DTC P1721 VEHICLE SPEED SENSOR MTR" .
❏ AT-147, "
DTC P1730 A/T INTERLOCK" .
❏ AT-150, "
DTC P1731 A/T 1ST ENGINE BRAKING" .
❏ AT-152, "
DTC P1752 INPUT CLUTCH SOLENOID VALVE" .
❏ AT-154, "
DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION" .
❏ AT-156, "
DTC P1757 FRONT BRAKE SOLENOID VALVE" .
❏ AT-158, "
DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION" .
❏ AT-160, "
DTC P1762 DIRECT CLUTCH SOLENOID VALVE" .
❏ AT-162, "
DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION" .
❏ AT-164, "
DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE" .
❏ AT-166, "
DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION" .
❏ AT-168, "
DTC P1772 LOW COAST BRAKE SOLENOID VALVE" .
❏ AT-170, "
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION" .
❏ AT-172, "
DTC P1815 MANUAL MODE SWITCH" .
❏ AT-178, "
DTC P1841 ATF PRESSURE SWITCH 1" .
❏ AT-180, "
DTC P1843 ATF PRESSURE SWITCH 3" .
❏ AT-182, "
DTC P1845 ATF PRESSURE SWITCH 5" .
❏ AT-184, "
DTC P1846 ATF PRESSURE SWITCH 6" .
4-2.Check at Idle
AT- 5 5
❏ AT- 1 9 3 , "Engine Cannot Be Started In “P” or “N” Position" .
❏ AT- 1 9 3 , "
In “P” Position, Vehicle Moves When Pushed" .
❏ AT- 1 9 4 , "
In “N” Position, Vehicle Moves" .
❏ AT- 1 9 5 , "
Large Shock (“N” to “D” Position)" .
❏ AT- 1 9 8 , "
Vehicle Does Not Creep Backward In “R” Position" .
❏ AT- 2 0 1 , "
Vehicle Does Not Creep Forward In “D” Position" .
4-3.Cruise test
AT- 5 7
Part 1
❏ AT- 2 0 3 , "
Vehicle Cannot Be Started From D1" .
❏ AT- 2 0 6 , "
A/T Does Not Shift: D1 → D2" .
❏ AT- 2 0 8 , "
A/T Does Not Shift: D2 → D3" .
❏ AT- 2 11 , "
A/T Does Not Shift: D3 → D4" .
❏ AT- 2 1 3 , "
A/T Does Not Shift: D4 → D5" .
❏ AT- 2 1 6 , "
A/T Does Not Perform Lock-up"
❏ AT- 2 1 8 , "A/T Does Not Hold Lock-up Condition" .
❏ AT- 2 2 0 , "
Lock-up Is Not Released" .
❏ AT- 2 2 1 , "
Engine Speed Does Not Return To Idle" .
AT-48
TROUBLE DIAGNOSIS
Revision: 2004 November 2004 FX35/FX45
44-3Part 2
AT- 6 0
❏ 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- 2 11 , "
A/T Does Not Shift: D3 → D4" .
Part 3
AT- 6 1
❏ AT-222, "Cannot Be Changed to Manual Mode" .
❏ AT-223, "
A/T Does Not Shift: 5th gear → 4th gear" .
❏ AT-225, "
A/T Does Not Shift: 4th gear → 3rd gear" .
❏ AT-227, "
A/T Does Not Shift: 3rd gear → 2nd gear" .
❏ AT-229, "
A/T Does Not Shift: 2nd gear → 1st gear" .
❏ AT-231, "
Vehicle Does Not Decelerate By Engine Brake" .
❏ Perform self-diagnostics. Enter checks for detected items. AT- 9 4
, AT-103
❏ AT-105, "DTC U1000 CAN COMMUNICATION LINE" .
❏ AT-108, "
DTC P0615 START SIGNAL CIRCUIT" .
❏ AT- 11 2 , "
DTC P0705 PARK/NEUTRAL POSITION SWITCH" .
❏ AT- 11 6 , "
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)" .
❏ AT-121, "
DTC P0725 ENGINE SPEED SIGNAL" .
❏ AT-121, "
DTC P0725 ENGINE SPEED SIGNAL" .
❏ AT-123, "
DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE" .
❏ AT-125, "
DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)" .
❏ AT-127, "
DTC P0745 LINE PRESSURE SOLENOID VALVE" .
❏ AT-129, "
DTC P1701 TRANSMISSION CONTROL MODULE (POWER SUPPLY)" .
❏ AT-133, "
DTC P1702 TRANSMISSION CONTROL MODULE (RAM)" .
❏ AT-134, "
DTC P1703 TRANSMISSION CONTROL MODULE (ROM)" .
❏ AT-135, "
DTC P1704 TRANSMISSION CONTROL MODULE (EEPROM)" .
❏ AT-136, "
DTC P1705 THROTTLE POSITION SENSOR" .
❏ AT-139, "
DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT" .
❏ AT-143, "
DTC P1716 TURBINE REVOLUTION SENSOR" .
❏ AT-145, "
DTC P1721 VEHICLE SPEED SENSOR MTR" .
❏ AT-147, "
DTC P1730 A/T INTERLOCK" .
❏ AT-150, "
DTC P1731 A/T 1ST ENGINE BRAKING" .
❏ AT-152, "
DTC P1752 INPUT CLUTCH SOLENOID VALVE" .
❏ AT-154, "
DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION" .
❏ AT-156, "
DTC P1757 FRONT BRAKE SOLENOID VALVE" .
❏ AT-158, "
DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION" .
❏ AT-160, "
DTC P1762 DIRECT CLUTCH SOLENOID VALVE" .
❏ AT-162, "
DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION" .
❏ AT-164, "
DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE" .
❏ AT-166, "
DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION" .
❏ AT-168, "
DTC P1772 LOW COAST BRAKE SOLENOID VALVE" .
❏ AT-170, "
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION" .
❏ AT-172, "
DTC P1815 MANUAL MODE SWITCH" .
❏ AT-178, "
DTC P1841 ATF PRESSURE SWITCH 1" .
❏ AT-180, "
DTC P1843 ATF PRESSURE SWITCH 3" .
❏ AT-182, "
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- 5 4
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 5
8❏ Erase the results of the self-diagnostics from the TCM.AT- 4 0,
AT- 1 0 4