
6E–153 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
10. To avoid backprobing the VSS and possibly
damaging a seal or terminal, the VSS output can be
tested at the point where the transmission harness
connected to the engine harness. The green 16-way
connector is adjacent to a blue 16-way connector,
and it can be easily accessed by removing the air
cleaner assembly. The green 16-way connector is
separated, and battery voltage is applied to the VSS
through the yellow wire at one corner of the
connector. The VSS output can be monitored with a
DVM connected to the blue wire with a black tracer.
The two wires are next to each other in the 16-way
connector . The test connections are made on the
transmission side of the connector, the side that is
not clipped to the body sheetmetal.11. The speedometer-to-ECM VSS signal wire is
spliced to a wire leading to the cruise control
module. If a short to ground or voltage is found
between the ECM and speedometer, it could be
located between the splice and the cruise control
module.
DTC P0502 –VSS No Signal
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
2Does the speedometer work?—Go to Step 10Go to Step 3
31. Disconnect the VSS connector.
2. Ignition “ON.”
3. Using a test light to battery +, probe the connector
ground wire.
Did the light illuminate?
—Go to Step 5Go to Step 4
4Repair the sensor ground.
Is the action complete?
—Verify repair—
51. Ignition “ON,” sensor disconnected.
2. Using a DVM, measure at the VSS connector
between ground and voltage supply.
Was the measurement near the specified value?
Battery
voltage
Go to Step 7Go to Step 6
6Repair the open or short to ground which may have
blown the meter fuse.
Is the action complete?
—Verify repair—
71. Ignition “ON,” VSS disconnected.
2. Using a DVM, measure at the VSS connector
between ground and the blue/black wire from the
speedometer.
Was the measurement near the specified value?
7.5-8 VGo to Step 9Go to Step 8
8Check for an open or short circuit between the
speedometer and the VSS.
Was an open or short circuit located?
—Verify repairGo to Step 9
9Replace the VSS.
Is the action complete?
—Verify repairGo to Step 10
10Replace the speedometer.
Is the action complete?
—Verify repairGo to Step 11

6E–174
4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1589 (Flash DTC 47)
Transmission SW Circuit Open/Short
060RW131
Circuit Description
The trans mission SW circuit receives current through
ELEC IG 10A fuse from the battery, current flowing in the
order of the trans mission SW and ECM.
Action Taken When the DTC Sets
The ECM will illuminate the malfunction indicator lamp
(MIL) the first time the fault is detected.
The ECM will store conditions which were present
when the DTC was set as Freeze Frame and in the
Failure Records data.
Conditions for Clearing the MIL/DTC
DTC P1589 can be cleared by using the Tech 2 “Clear
Info” function or by disconnecting the ECM battery
feed.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM – Inspect harness connectors
for backed-out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal-to-wire connection.
Damaged harness – Inspect the wiring harness for
damage. If the harness appears to be OK, observe the
throttle position display on the Tech 2 while moving
connectors and wiring harnesses related to the TP
sensor. A change in the display will indicate the
location of the fault.
If DTC P1589 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
DTC P1589 – Transmission Circuit Open/Short
StepActionVa l u e ( s )Ye sNo
1Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
2Check the Fuse 10A for a open circuit and replace the
Fuse if necessary.
Did the Fuse require replacement?
—Verify repairGo to Step 3

6E–175 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
DTC P1589 – Transmission Circuit Open/Short
StepNo Ye s Va l u e ( s ) Action
31. Ignition “ON,” engine “OFF.”
2. Review and record Tech 2 Failure Records data.
3. Operate the vehicle within Failure Records
conditions as noted.
4. Using a Tech 2, monitor the “DTC” info for DTC
P1589.
Does the Tech 2 indicate DTC P1589 failed?
—
Go toStep 4
(A/T)
Go toStep 6
(M/T)
Refer to
Diagnostic
Aids
4Check the Indicator Lamp correct indicated for a
correct indication on the Meter. (A/T only)
Did the Indicator Lamp correct indicated?
—Go to Step 5Go to Step 8
5Check the Trans Mission SW signal circuit for a poor
connection at the ECM and replace the terminal if
necessary.
Did the terminal require replacement?
—Verify repairGo to Step 8
6Check the Trans Mission SW circuit for a poor
connection at the Trans Mission SW and replace the
terminal if necessary.
Did the terminal require replacement?
—Verify repairGo to Step 7
7Replace the Trans Mission SW.
Is the action complete?
—Verify repairGo to Step 8
8Replace the ECM (Refer to the Data Programming in
Case of ECM change).
Is the action complete?
—Verify repair—

6E–179 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Surges and/or Chuggles Symptom
StepActionVa l u e ( s )Ye sNo
1DEFINITION:
Engine power variation under steady throttle or cruise.
Feels like the vehicle speeds up and slows down with
no change in the accelerator pedal.
Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
—Verify repairGo to Step 3
3Was a visual/physical check performed?
—Go to Step 4
Go to Visual/
Physical
Check
4Be sure that the driver understands transmission
torque converter clutch and A/C compressor operation
as explained in the owner’s manual.
Inform the customer how the TCC and the A/C clutch
operate.
Is the customer experiencing a normal condition?
—System OKGo to Step 5
51. Check the priming pump. Refer to Fuel System.
2. If a problem is found, operate the priming pump.
Was a problem found?
—Verify repairGo to Step 6
61. Injector Test
Operate the each injector by Tech 2 with the
ignition “ON” and check if the working noise
confirm.
2. If a problem is found, check the harness and repair
as necessary.
Is the action complete?
—Verify repairGo to Step 7
71. Check ECM grounds for the cleanliness, tightness
and proper locations. Refer to the ECM wiring
diagrams in
Electrical Diagnosis.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 8
81. Check AP sensor connections.
2. If a problem is found, replace the faulty terminals as
necessary. Refer to
Electrical Diagnosis for wiring
repair procedures.
Was a problem found?
—Verify repairGo to Step 9
91. Visually/physically check vacuum hoses for splits,
kinks, and proper connections and routing as
shown on the “Vehicle Emission Control
Information” label.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 10

6E–181 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Lack of Power, Sluggish or Spongy Symptom
StepActionVa l u e ( s )Ye sNo
1DEFINITION:
Engine delivers less than expected power. Little or no
increase in speed when accelerator pedal is pushed
down part-way.
Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
—Verify repairGo to Step 3
3Was a visual/physical check performed?
—Go to Step 4
Go to Visual/
Physical
Check
41. Remove and check the air filter element for dirt or
restrictions. Refer to
Air Intake System in
On-Vehicle Service.
2. Replace the air filter element if necessary.
Was a repair required?
—Verify repairGo to Step 5
51. Check AP sensor system. Refer to AP sensor
diagnostic
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 6
61. Check for water-or alcohol-contaminated fuel.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 7
71. Using a Tech 2, Injector test.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 8
81. Check the ECM grounds for the cleanliness,
tightness and proper locations. Refer to the ECM
wiring diagrams in
Electrical Diagnosis.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 9
91. Check the exhaust system for possible restriction:
Inspect the exhaust system for damaged or
collapsed pipes.
Inspect the muffler for heat distress or possible
internal failure.
Check for a possible plugged catalytic
converter by checking the exhaust system
back pressure. Refer to
Restricted Exhaust
System Check
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 10
101. Check the torque converter clutch (TCC) for proper
operation. Refer to
Transmission Diagnosis.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 11

6E–183 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Rough, Unstable, or Incorrect Idle, Stalling Symptom
StepActionVa l u e ( s )Ye sNo
1DEFINITION:
Engine runs unevenly at idle. If severe, the engine or
vehicle may shake. Engine idle speed may vary in
RPM. Either condition may be severe enough to stall
the engine.
Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
—Go to Step 6Go to Step 3
3Was a visual/physical check performed?
—Go to Step 4
Go to Visual/
Physical
Check
41. Check the ECM grounds for cleanliness, tightness
and proper routing. Refer to the ECM wiring
diagrams in
Electrical Diagnosis.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 5
51. Check for incorrect idle speed. Ensure that the
following conditions are present:
The engine is fully warm.
The accessories are “OFF.”
2. Using a Tech 2, monitor the AP position.
Is the AP position within the specified values?
0%Go to Step 10Go to Step 9
61. Visually/physically inspect for the following
conditions:
Restricted air intake system. Check for a
possible collapsed air intake duct, restricted
air filter element, or foreign objects blocking
the air intake system.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 7
71. Injector Test
Operate the each injector by Tech 2 with the
ignition “ON” and check if the working noise
confirm.
2. If a problem is found, check the harness or replace
the injector.
Is the action complete?
—Verify repairGo to Step 8
81. Check the transmission range switch circuit. Use a
Tech 2 and be sure the Tech 2 indicates that the
vehicle is in drive with the gear selector in drive or
overdrive.
2. If a problem is found, diagnose and repair the
transmission range switch as necessary (Refer to
Automatic Transmission Diagnosis).
Was a problem found?
—Verify repairGo to Step 9

6E–186
4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Poor Fuel Economy Symptom
StepNo Ye s Va l u e ( s ) Action
111. Check the TCC operation. Refer to Transmission
Diagnosis
.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 12
121. Check the exhaust system for possible restriction:
Inspect the exhaust system for damaged or
collapsed pipes.
Inspect the muffler for heat distress or possible
internal failure.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 13
13Check for proper calibration of the speedometer.
Does the speed indicated on the speedometer closely
match the vehicle speed displayed on the Tech 2?
—Go to Step 15Go to Step 14
14Diagnose and repair an inaccurate speedometer
condition as necessary. Refer to
Vehicle Speed
Sensor
in Electrical Diagnosis.
Was a problem found?
—Verify repair—
151. Check the air intake system and the crankcase for
air leaks. Refer to
Air Intake System and
Crankcase Ventilation System.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 16
161. Review all diagnostic procedures within this table.
2. When all procedures have been completed and no
malfunctions have been found, review/inspect the
following:
Visual/physical inspection
Te c h 2 d a t a
Freeze Frame data/Failure Records buffer
All connections within a suspected circuit
and/or system.
3. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 17
17Perform the procedure in Injector Test.
Was the fuel pressure normal?
—
Contact
Te c h n i c a l
Assistance
Verify repair

6E–189 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Cuts Out, Symptom
StepActionVa l u e ( s )Ye sNo
1DEFINITION:
Steady pulsation or jerking that follows engine speed;
usually more pronounced as engine load increases.
Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2
Go to OBD
System
Check
21. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
—Go to Step 7Go to Step 3
3Was a visual/physical check performed?
—Go to Step 4
Go to Visual/
Physical
Check
41. Check the ECM grounds for clearness, tightness
and proper routing. Refer to the ECM wiring
diagrams in
Electrical Diagnosis.
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 5
51. Check for incorrect idle speed. Ensure that the
following conditions are present:
The engine is fully warm.
The accessories are “off.”
2. Using a Tech 2, monitor the AP position.
Is the AP position within the specified values?
0%Go to Step 6Go to Step 7
61. Visually/physically inspect for the following
conditions:
Restricted air intake system. Check for a
possible collapsed air intake duct, restricted
air filter element, or foreign objects blocking
the air intake system.
Check the Throttle body.
Large vacuum leak. Check for a condition that
causes a large vacuum leak, such as an
incorrectly installed or faulty VSV or brake
booster hose disconnected .
2. If a problem is found, repair as necessary.
Was a problem found?
—Verify repairGo to Step 7
7Using a Tech 2, monitor the AP angle with the engine
idling.
Is the AP angle at the specified value and steady?
0%Go to Step 8
Refer to DTC
P0123
for
further
diagnosis
81. Check the transmission range switch circuit. Use a
Tech 2 and be sure the Tech 2 indicates that the
vehicle is in drive with the gear selector in drive or
overdrive.
2. If a problem is found, diagnose and repair the
transmission range switch as necessary.
Was a problem found?
—Verify repairGo to Step 9