AUTOMATIC TRANSMISSION (4 A/T) 7B1-13
Malfunction Indicator Lamp (MIL) Check
Refer to the same item in Section 6-1 for checking procedure.
“O/D OFF” Lamp Check
1) Check that O/D off switch button is at OFF position (pushed).
2) Turn ignition switch ON.
3) Check that “O/D OFF” lamp lights for about 2 – 4 sec. and
then goes OFF.
If anything faulty is found, advance “DIAGNOSTIC FLOW
TABLE B-1 or B-2 “O/D OFF” LAMP CIRCUIT CHECK”.
“POWER” Lamp Check
1) Check that Power/Normal change switch button is at Normal
position.
2) Turn ignition switch ON.
3) Check that “POWER” lamp lights for about 2 – 4 sec. and
then goes OFF.
If anything faulty is found, advance “DIAGNOSTIC FLOW
TABLE B-3 or B-4 “POWER” LAMP CIRCUIT CHECK”.
Diagnostic Trouble Code (DTC) Check
Refer to the same item in Section 6-1 for checking procedure.
Diagnostic Trouble Code Clearance
Refer to the same item in Section 6-1 for clearance procedure.
7B1-14 AUTOMATIC TRANSMISSION (4 A/T)
Diagnostic Trouble Code Table
Refer to the same item in Section 6-1.
Fail Safe Table
Refer to the same item in Section 6-1.
Visual Inspection
Visually check following parts and systems.
A/T Basic Check
This inspection is important for troubleshooting when PCM (ECM) has detected no DTC and no abnormality has
been noted in visual inspection. Follow flow table carefully.INSPECTION ITEM REFERRING SECTION
•A/T fluid - - - - - level, leakage, color SECTION 0B
•A/T fluid hoses - - - - - disconnection, looseness, deterioration SECTION 7B1
•Throttle (accelerator) cable - - - - - play, installation SECTION 6E2
•A/T throttle cable - - - - - play, installation SECTION 7B1
•A/T select cable - - - - - installation, operation SECTION 7B1
•Engine oil - - - - - level, leakage SECTION 0B
•Engine coolant - - - - - level, leakage SECTION 0B
•Battery - - - - - fluid level, corrosion of terminal
•Connectors of electric wire harness - - - - - disconnection, friction Section 6-1 or 7B1
•Fuses - - - - - burning SECTION 8
•Parts - - - - - installation, damage
•bolt - - - - - looseness
•Other parts that can be checked visually
•Also check following items at engine start, if possible.
–“O/D OFF” lamp - - - - - Operation SECTION 7B1
–“POWER” lamp - - - - - Operation SECTION 7B1
–Malfunction indicator lamp (“SERVICE ENGINE SOON” lamp) - -
- - - OperationSection 6-1
–Charge warning lamp - - - - - Operation SECTION 6H
–Engine oil pressure warning lamp - - - - - Operation SECTION 8C (SECTION 6A2 for pres-
sure check)
–Engine coolant temp. meter - - - - - Operation
–Other parts that can be checked visually
Step Action Yes No
1Was “AUTOMATIC TRANSMISSION DIAGNOSTIC
FLOW TABLE” performed?Go to Step 2. Go to “AUTOMATIC
TRANSMISSION DIAG-
NOSTIC FLOW TABLE”.
2Perform “MANUAL ROAD TEST” in this section.
Is it OK?Go to Step 3. Go to Step 4.
3Proceed to “TROUBLE DIAGNOSIS TABLE 1” in this
section.
Is trouble identified?Repair or replace
defective parts.Go to Step 5.
AUTOMATIC TRANSMISSION (4 A/T) 7B1-15
Trouble Diagnosis Table 1
Trouble Diagnosis Table 2
TRANSMISSION FLUID
RUNNING CONDITION
4 Perform stall test, time rag test, line pressure test,
engine brake test and “P” range test referring to
“STALL TEST”, “LINE PRESSURE TEST”, “ENGINE
BRAKE TEST” and ““P” RANGE TEST” in this section.
Are the test results satisfactory?Go to Step 5. Proceed to “TROUBLE
DIAGNOSIS TABLE 3” in
this section.
5 Proceed to “TROUBLE DIAGNOSIS TABLE 2” in this
section.
Is trouble identified?Repair or replace
defective parts.Proceed to “TROUBLE
DIAGNOSIS TABLE 3” in
this section. Step Action Yes No
Condition Possible Cause Correction
TCC does not operateBrake pedal (stop lamp) switch or its circuit
faulty (H25 engine only)Refer to “DIAGNOSTIC FLOW
TABLE A-1” in this section.
4WD low switch or its circuit faulty
Engine coolant temp. sensor or its circuit faulty
Cruise control signal circuit faulty (if equipped)
Gear does not change
to 4thO/D off switch or its circuit faulty Refer to “DIAGNOSTIC FLOW
TABLE A-2” in this section.
4WD low switch or its circuit faulty
Engine coolant temp. sensor or its circuit faulty
Cruise control signal circuit faulty (if equipped)
Condition Possible Cause Correction
Low fluid pressureClogged oil pump strainer Wash strainer.
Malfunction of pressure regulator valve Overhaul valve body.
High fluid pressurePressure regulator valve Overhaul valve body.
Condition Possible Cause Correction
Unable to run in all
rangeRegulator valve stick Replace.
Clogged oil strainer Wash strainer.
Seized or broken planetary gear Repair or replace.
Faulty manual valve Replace.
Poor 1st speed run-
ning or excessive slip-
page in “D” or “2”Faulty 1–2 shift valve Replace.
AUTOMATIC TRANSMISSION (4 A/T) 7B1-17
GEAR SHIFT
ABNORMAL NOISE
Scan Tool Data
Refer to Section 6-1.
Inspection of PCM and Its Circuit
Refer to Section 6-1.
Wire Harness and Connectors
Refer to Section 6-1.Condition Possible Cause Correction
Poor 1–2 shift, exces-
sive slippageFluid pressure leakage to overdrive clutch due
to wear or breakage of O/D case seal ringReplace.
Faulty second brake Replace.
Broken O-ring of second brake piston Replace.
Faulty second coast brake (in “2” range) Replace.
Poor 2–3 shift, exces-
sive slippageFluid pressure leakage to overdrive clutch due
to wear or breakage of O/D case seal ringReplace.
Worn direct clutch bushing Replace.
Direct clutch slipping Replace.
Foreign material caught in direct clutch piston
check ballReplace.
Poor start or surging
in “D” rangeFluid pressure leakage of forward clutch due to
wear or breakage of O/D case seal ringReplace.
Malfunction of forward clutch Replace.
Poor 3–4 shift, exces-
sive slippageFaulty overdrive brake Replace.
Faulty overdrive clutch Replace.
Poor start or juddering
in “R” rangeFluid pressure leakage of direct clutch due to
wear or breakage of oil center support seal ringReplace.
Worn direct clutch Replace.
Excessive shock on
1– 2 shiftFaulty one-way clutch Replace.
Non operate lock-up
systemFaulty torque converter Replace.
Condition Possible Cause Correction
Abnormal noise in “P”
or “N” rangeWorn oil pump Replace.
7B1-18 AUTOMATIC TRANSMISSION (4 A/T)
Table A-1 : No TCC Lock-Up Occurs
SYSTEM DESCRIPTION
PCM turns TCC solenoid OFF under any of the following conditions.
•Brake pedal switch : ON
•4WD LOW switch : ON
•Cruise control module : TCC OFF command signal is output (if equipped).
•ECT : ECT < 30 °C (86 °F)
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 person, a driver and tester, on a level road.
Step Action Yes No
1Was “AUTOMATIC TRANSMISSION DIAG-
NOSTIC FLOW TABLE” performed?Go to Step 2. Go to “AUTOMATIC
TRANSMISSION DIAG-
NOSTIC FLOW TABLE” in
this section.
2 ECT check :
1) Warm up engine to normal operating tem-
perature.
2) Check ECT using scan tool.
Is ECT more than 30 °C (86 °F)?Go to Step 3. Faulty ECT sensor, its cir-
cuit or engine cooling sys-
tem.
If OK, substitute a known-
good PCM and recheck.
3 Perform running test under the following condi-
tions and check voltage between C51-1-8 termi-
nal of PCM coupler and ground.
•Normal mode in “D” range.
•Transfer “2H” position.
•Cruise control is not operated (if equipped).
•Brake pedal released.
•Drive vehicle with TCC ON condition refer-
ring to “TCC LOCK-UP DIAGRAM” in this
section.
Is it battery voltage?Faulty TCC solenoid
valve, its circuit or trans-
mission.Go to Step 4.
4 Brake switch signal inspection :
With ignition switch ON, check voltage between
E61-34 terminal of PCM coupler terminal and
ground.
Brake switch specification
Brake pedal released : 0 V
Brake pedal depressed : Battery voltage
Is the result as specified?Go to Step 5. Faulty brake pedal switch
or its circuit.
If OK, substitute a known-
good PCM and recheck.
7B1-20 AUTOMATIC TRANSMISSION (4 A/T)
Table A-2 : No Gear Shift to O/D
SYSTEM DESCRIPTION
PCM does not shift to O/D gear under any of the following conditions.
•O/D off switch : ON
•4WD LOW switch : ON
•Cruise control module : O/D OFF command signal is output (if equipped).
•ECT : ECT < 30 °C (86 °F)
TROUBLESHOOTING
WARNING:
When performing a road test, select a place where there is no traffic or possibility of a traffic acci-
dent and very careful during testing to avoid occurrence of an accident.
Road test should be carried out with 2 person, a driver and tester, on a level road.
Step Action Yes No
1Was “AUTOMATIC TRANSMISSION DIAG-
NOSTIC FLOW TABLE” performed?Go to Step 2. Go to “AUTOMATIC
TRANSMISSION DIAG-
NOSTIC FLOW TABLE” in
this section.
2 ECT check :
1) Warm up engine to normal operating tem-
perature.
2) Check ECT using scan tool.
Is ECT more than 30 °C (86 °F)?Go to Step 3. Faulty ECT sensor, its cir-
cuit or engine cooling sys-
tem.
If OK, substitute a known-
good PCM and recheck.
3 Perform running test under the following condi-
tions and check voltage between C51-1-2 termi-
nal of PCM coupler and ground, C51-1-1
terminal of PCM coupler and ground.
•O/D off switch OFF (“O/D OFF” lamp OFF).
•Normal mode in “D” range.
•Transfer “2H” position.
•Cruise control is not operated (if equipped).
•Drive vehicle with 4th gear condition refer-
ring to “Gear shift diagram” in this section.
Is each voltage about 0 V?Faulty shift solenoid valve,
its circuit or transmission“GRN” wire or “GRN/
RED” wire shorted to
power circuit.
If OK, go to Step 4.
4 O/D off switch signal inspection :
With ignition switch ON, check voltage between
E61-33 terminal of PCM coupler and ground.
“O/D” cut switch specification
“O/D” cut switch OFF : Battery voltage
“O/D” cut switch ON : 0 V
Is the result as specified?Go to Step 5. Faulty O/D off switch or its
circuit.
If OK, substitute a known-
good PCM and recheck.
AUTOMATIC TRANSMISSION (4 A/T) 7B1-23
Table B-2 : “O/D OFF” Light Circuit Check (“O/D OFF” Light Comes ON
Steadily)
WIRING DIAGRAM
Refer to “TABLE B-1” in this section.
TROUBLESHOOTING
[A] for Step 1/[B] for Step 4Step Action Yes No
1 Check O/D off switch status.
Press O/D off switch button (1).
Does “O/D OFF” lamp come ON steadily?Go to Step 2. System is OK.
2 Check lamp circuit for short.
1) Turn ignition switch OFF and disconnect
PCM connectors.
2) Turn ignition switch ON.
Does “O/D OFF” lamp come ON steadily?“WHT/BLK” circuit
shorted to ground.Go to Step 3.
3 Check O/D off switch circuit.
1) Check resistance between terminal E61-33
of disconnected PCM connector and body
ground with O/D off switch button (1)
released.
Is continuity indicated?Go to Step 4. Check PCM ground circuit
for open.
If ground circuit is OK,
substitute a known-good
PCM and recheck.
4 Check O/D off switch for operation.
1) Remove console box.
2) Disconnect O/D off switch connector.
3) Check continuity between switch terminals
under each condition below.
O/D switch operation
With O/D off switch button (1) released :
No continuity
With O/D off switch button (1) pressed :
Continuity
Is check result satisfactory?“YEL/RED” circuit shorted
to ground.Replace O/D off switch.
AUTOMATIC TRANSMISSION (4 A/T) 7B1-25
Table B-4 : “POWER” Light Circuit Check (“POWER” Light Comes ON
Steadily)
WIRING DIAGRAM
Refer to “TABLE B-3” in this section.
TROUBLESHOOTING
[A] for Step 1/[B] for Step 4Step Action Yes No
1 Check Power/Normal change switch position.
Is switch button at Normal position?Go to Step 2. Set Power/Normal
change switch at Nor-
mal position.
2 Check lamp circuit for short.
1) Turn ignition switch OFF and disconnect PCM
connectors.
2) Turn ignition switch ON.
Does “POWER” lamp come ON steadily?“GRY/BLU” circuit
shorted to ground.Go to Step 3.
3 Check Power/Normal change switch circuit.
1) Check resistance between terminal E61-31 of dis-
connected PCM connector and body ground with
P/N change switch OFF.
Is continuity indicated?Go to Step 4. Check PCM ground
circuit for open.
If ground circuit is OK,
substitute a known-
good PCM and
recheck.
4 Check Power/Normal change switch for operation.
1) Remove Power/Normal change switch.
2) Check continuity between switch terminals “4” and
“5” under each condition below.
Normal position: No continuity
Power position: Continuity.
Is check result satisfactory?“ORN/BLU” circuit
shorted to ground.Replace Power/Normal
change switch.