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:
AT-108
DTC P0615 START SIGNAL CIRCUIT
Revision: 2004 November 2004 FX35/FX45
DTC P0615 START SIGNAL CIRCUITPFP:25230
DescriptionACS007AQ
Prohibits cranking other than at “P” or “N” position.
CONSULT-II Reference ValueACS007AR
On Board Diagnosis LogicACS007AS
This is not an OBD-II self-diagnostic item.
Diagnostic trouble code “STARTER RELAY/CIRC” with CONSULT-II or 14th judgement flicker without
CONSULT-II is detected when starter relay is switched “ON” other than at “P” or “N” position. (Or when
switched “OFF” at “P” or “N” position).
Possible CauseACS007AT
Harness or connectors
(Starter relay and TCM circuit is open or shorted.)
Starter relay circuit
DTC Confirmation ProcedureACS007AU
NOTE:
If “DTC Confirmation Procedure” has been previously conducted, always turn ignition switch “OFF”
and wait at least 10 seconds before conducting the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Start engine.
4. Vehicle start for at least 2 consecutive seconds.
5. If DTC is detected, go to AT- 11 0 , "
Diagnostic Procedure" .
Item name Condition Display value
STARTER RELAYSelector lever in N and P positions. ON
Selector lever in other positions. OFF
SAT014K
AT-110
DTC P0615 START SIGNAL CIRCUIT
Revision: 2004 November 2004 FX35/FX45
TCM terminals and data are reference value. Measured between each terminal and ground.
Diagnostic ProcedureACS007AW
1. CHECK STARTER RELAY
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode
for “A/T” with CONSULT-II and check monitor “STARTER
RELAY” ON/OFF.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Check the voltage between the IPDM E/R connector and
ground.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. DETECT MALFUNCTIONING ITEM
Check the following items:
Starter relay, Refer to SC-10, "System Description" .
IPDM E/R, Refer to PG-18, "IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE
ROOM)" .
Disconnections or short-circuits in the harness between A/T assembly harness connector and IPDM E/R.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
TerminalWire
colorItem Condition Data (Approx.)
9GYStarter relaySelector lever in “N” and “ P” positions. Battery voltage
Selector lever in other positions. 0V
Item name Condition Display value
STARTER RELAYSelector lever in N and P positions. ON
Selector lever in other positions. OFF
PCIA0056E
Item ConnectorTerminal
(Wirer color)Shift position Voltage (Approx.)
Starter
relayE953
(GY)GroundN and P Battery voltage
R, D and M 0V
SCIA2103E
AT-112
DTC P0705 PARK/NEUTRAL POSITION SWITCH
Revision: 2004 November 2004 FX35/FX45
DTC P0705 PARK/NEUTRAL POSITION SWITCHPFP:32006
DescriptionACS007AX
The park/neutral position (PNP) switch includes a transmission range switch.
The transmission range switch detects the selector lever position and sends a signal to the TCM.
CONSULT-II Reference ValueACS007AY
On Board Diagnosis LogicACS007AZ
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “PNP SW/CIRC” with CONSULT-II or P0705 without CONSULT-II is detected
under the following conditions.
–When TCM does not receive the correct voltage signal from the PNP switch 1, 2, 3, 4 based on the gear
position.
–When no other position but “P” position is detected from “N” positions.
Possible CauseACS007B0
Harness or connectors
[Park/neutral position (PNP) switch 1, 2, 3, 4 and TCM circuit is open or shorted.]
Park/neutral position (PNP) switch 1, 2, 3, 4
DTC Confirmation ProcedureACS007B1
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 2
consecutive seconds.
THRTL POS SEN: More than 1.2V
5. If DTC is detected, go to AT- 11 4 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value
SLCTLVR POSISelector lever in “N” and “P” positions. N/P
Selector lever in “R” position. R
Selector lever in “D” position. D
SAT014K
AT-114
DTC P0705 PARK/NEUTRAL POSITION SWITCH
Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureACS007B3
1. CHECK PNP SW CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “A/T”
with CONSULT-II.
3. Read out “N/P”, “R” and “D” position switches moving selector
lever to each position.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2. CHECK TCM
Perform TCM input/output signals inspection. Refer to AT- 9 0 , "
TCM Input/Output Signal Reference Values" .
OK or NG
OK >> GO TO 3.
NG >> GO TO 4.
3. CHECK TERMINAL CORD ASSEMBLY
1. Remove control valve with TCM. Refer to AT- 2 4 2 , "
Control Valve with TCM and A/T Fluid Temperature
Sensor 2" .
2. Disconnect A/T assembly harness connector and control valve with TCM harness connector.
3. Check continuity between A/T assembly harness connector terminal and control valve with TCM harness
connector terminal. Refer to AT- 11 3 , "
Wiring Diagram — AT — PNP/SW" .
4. If OK, check harness for short to ground and short to power.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT- 2 4 2 , "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2" .
NG >> Replace open circuit or short to ground and short to power in harness or connectors.
4. DETECT MALFUNCTIONING ITEM
Check the following items:
Harness for short or open between battery and A/T assembly harness connector terminals 1, 2
Harness for short or open between ignition switch and A/T assembly harness connector terminal 6
10A fuse (No. 37, located in the fuse and fusible link block) and 10A fuse (No. 83, located in the IPDM E/
R).
Ignition switch, Refer to PG-3, "POWER SUPPLY ROUTING CIRCUIT" .
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
Item name Condition Display value
SLCTLVR POSISelector lever in “N” and “P” positions. N/P
Selector lever in “R” position. R
Selector lever in “D” position. D
SCIA5296E
AT-116
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)
Revision: 2004 November 2004 FX35/FX45
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)PFP:32702
DescriptionACS007B4
The revolution sensor detects the revolution of the idler gear parking pawl lock gear and emits a pulse signal.
The pulse signal is sent to the TCM which converts it into vehicle speed.
CONSULT-II Reference ValueACS007B5
On Board Diagnosis LogicACS007B6
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “VEH SPD SEN/CIR AT” with CONSULT-II or P0720 without CONSULT-II is
detected under the following conditions.
–When TCM does not receive the proper voltage signal from the sensor.
–After ignition switch is turned “ON”, irregular signal input from vehicle speed sensor MTR before the vehi-
cle starts moving.
Possible CauseACS007B7
Harness or connectors
(Sensor circuit is open or shorted.)
Revolution sensor
Vehicle speed sensor MTR
DTC Confirmation ProcedureACS007B8
CAUTION:
Always drive vehicle at a safe speed.
Be careful not to rev engine into the red zone on the tachometer.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Drive vehicle and check for an increase of “VHCL/S SE·A/T”
value in response to “VHCL/S SE·MTR” value.
If the check result is NG, go to AT- 11 9 , "
Diagnostic Procedure" .
If the check result is OK, go to following step.
4. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-II.
5. Start engine and maintain the following conditions for at least 5
consecutive seconds.
VHCL SPEED SE: 30 km/h (19 MPH) or more
THRTL POS SEN: More than 1.0/8
Selector lever: “D” position
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving
conditions required for this test.
If the check result is NG, go to AT- 11 9 , "
Diagnostic Procedure" .
If the check result is OK, go to following step.
6. Maintain the following conditions for at least 5 consecutive seconds.
ENGINE SPEED: 3,500 rpm or more
THRTL POS SEN: More than 1.0/8
Selector lever: “D” position
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving
conditions required for this test.
If the check result is NG, go to AT- 11 9 , "
Diagnostic Procedure" .
Item name Condition Display value (km/h)
VHCL/S SE·A/T During driving Approximately matches the speedometer reading.
SAT014K
DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)
AT-119
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureACS007BA
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for
“A/T” with CONSULT-II.
3. Start the engine.
4. Read out the value of “VHCL/S SE·A/T” while driving.
Check the value changes according to driving speed.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2. CHECK TCM
Perform TCM input/output signals inspection. Refer to AT- 9 0 , "
TCM Input/Output Signal Reference Values" .
OK or NG
OK >> GO TO 3.
NG >> GO TO 4.
3. CHECK TERMINAL CORD ASSEMBLY
1. Remove control valve with TCM. Refer to AT- 2 4 2 , "
Control Valve with TCM and A/T Fluid Temperature
Sensor 2" .
2. Disconnect A/T assembly harness connector and control valve with TCM harness connector.
3. Check continuity between A/T assembly harness connector terminal and control valve with TCM harness
connector terminal. Refer to AT- 11 8 , "
Wiring Diagram — AT — VSSA/T" .
4. If OK, check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Replace open circuit or short to ground and short to power in harness or connectors.
4. DETECT MALFUNCTIONING ITEM
Check the following items:
Harness for short or open between battery and A/T assembly harness connector terminals 1, 2
Harness for short or open between ignition switch and A/T assembly harness connector terminal 6
10A fuse (No. 37, located in the fuse and fusible link block) and 10A fuse (No. 83, located in the IPDM E/
R).
Ignition switch, Refer to PG-3, "POWER SUPPLY ROUTING CIRCUIT" .
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
Item name Condition Display value (km/h)
VHCL/S SE·A/T During drivingApproximately matches the
speedometer reading.
SCIA2148E