The TCM receives a signal from the vehicle speed sensor, accelera-
tor pedal position sensor (throttle position sensor) or PNP switch.
Then provides shift control or lock-up control via A/T solenoid valves.
The TCM also communicates with the ECM by means of a signal
transmitted from sensing elements used with the OBD-related parts
of the A/T system for malfunction-diagnostic purposes. The TCM is
capable of diagnosing malfunctioning parts while the ECM can store
malfunctions 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 an error that occurs intermit-
tently rather than continuously. Most intermittent errors are caused
by poor electric connections or improper wiring. In this case, careful
checking of suspected circuits may help prevent the replacement of
good parts.
A visual check may not find the cause of the errors. A road test with
CONSULT-III (or GST) or a circuit tester connected should be per-
formed. Follow the “DETAILED FLOW”.

Before undertaking actual checks, take a few minutes to talk with the
customer who has the driveability complaint. The customer can sup-
ply good information about such errors, especially intermittent ones.
Find out what symptoms are present and under what conditions they
occur. A “Diagnostic work sheet” as shown in the example (Refer to

TM-6

) 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.

DETAILED FLOW

COLLECT THE INFORMATION FROM THE CUSTOMER

Get the detailed information from the customer about the symptom (the condition and the environment when
the incident/malfunction occurred) using diagnosis worksheet. Refer to

TM-6, "Diagnostic Work Sheet"

>> GO TO 2.

CHECK SYMPTOM 1

Check the following items based on the information obtained from the customer.
• Fail-safe. Refer to

TM-111, "Fail-Safe"

• A/T fluid inspection. Refer to

TM-141, "Inspection"

• Stall test. Refer to

TM-146, "Inspection and Judgment"

• Line pressure test. Refer to

TM-147, "Inspection and Judgment"

SAT631IB

SAT632I

SEF234G

TM-6

< BASIC INSPECTION >

[5AT: RE5R05A]

DIAGNOSIS AND REPAIR WORK FLOW

>> GO TO 3.

CHECK DTC

Check DTC.

Perform the following procedure if DTC is detected.

• Record DTC.
• Erase DTC. Refer to

TM-36, "Diagnosis Description"

Is any DTC detected?

YES

>> GO TO 4.

>> GO TO 6.

PERFORM DIAGNOSTIC PROCEDURE

Perform “Diagnosis Procedure” for the displayed DTC.

>> GO TO 5.

PERFORM DTC CONFIRMATION PROCEDURE

Perform “DTC CONFIRMATION PROCEDURE” for the displayed DTC.

Is any DTC detected?

YES

>> GO TO 4.

>> GO TO 6.

CHECK SYMPTOM 2

Try to confirm the symptom described by the customer.

Is any malfunction present?

YES

>> GO TO 7.

>> INSPECTION END

ROAD TEST

Perform “ROAD TEST”. Refer to

TM-149, "Description"

>> GO TO 8.

CHECK SYMPTOM 3

Try to confirm the symptom described by the customer.

Is any malfunction present?

YES

>> GO TO 2.

>> INSPECTION END

Diagnostic Work Sheet

INFOID:0000000003130456

INFORMATION FROM CUSTOMER

KEY POINTS

• WHAT..... Vehicle and A/T model
• WHEN..... Date, Frequencies
• WHERE..... Road conditions
• HOW..... Operating conditions, Symptoms

Customer name

MR/MS

Model and Year

VIN

Trans. Model

Engine

Mileage

Malfunction Date

Manuf. Date

In Service Date

Frequency

Continuous

Intermittent (

times a day)

DIAGNOSIS AND REPAIR WORK FLOW

TM-7

< BASIC INSPECTION >

[5AT: RE5R05A]

DIAGNOSTIC WORK SHEET

Symptoms

Vehicle does not move.

(

Any position

Particular position)

No up-shift

(

1st

→

2nd

→

3rd

→

4th

→

5th)

No down-shift

(

5th

→

4th

→

3rd

→

2nd

→

1st)

Lock-up malfunction

Shift point too high or too low.

Shift shock or slip

(

→

Lock-up

Any drive position)

Noise or vibration

No kick down

No pattern select

Others

(

)

A/T CHECK indicator lamp

Continuously lit

Not lit

Malfunction indicator lamp (MIL)

Continuously lit

Not lit

Read the item on cautions concerning fail-safe and understand the customer's complaint.

TM-111

A/T fluid inspection, stall test and line pressure test

A/T fluid inspection

TM-141

Leak (Repair leak location.)

State

Amount

Stall test

TM-146

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 test - Suspected part:

TM-147

Perform self-diagnosis. — Check detected items to repair or replace malfunctioning part.

TM-40

Perform road test.

4-1

Check before engine is started

TM-149

4-2

Check at idle

TM-149

4-3

Cruise test

Part 1

TM-150

Part 2

TM-151

Part 3

TM-152

Check malfunction phenomena to repair or replace malfunctioning part after completing all road tests.

Refer to

TM-115, "Symptom Table"

Drive vehicle to check that the malfunction phenomenon has been resolved.

Erase the results of the self-diagnosis from the TCM and the ECM.

EC-100

TM-36

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