Page 5576 of 6000

6E–147 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
DTC P1486 – ITP Sensor High Voltage
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
21. Ignition “ON,” engine “OFF.”
2. With the throttle closed by the hand, observe the
“ITP Sensor” display on the Tech 2.
Is the “ITP Sensor” above the specified value?
4.88 VGo to Step 4Go to Step 3
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 “DTC” info for DTC P1486.
Does the Tech 2 indicate DTC P1486 failed.
—Go to Step 4
Refer to
Diagnostic
Aids
4Check for poor electrical connections at the ITP sensor
and replace terminals if necessary.
Did any terminals require replacement?
—Verify repairGo to Step 5
51. 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
P1486.
Dose the Tech 2 indicate DTC P1486 failed.
—Go to Step 6
Refer to
Diagnostic
Aids
6Replace the intake throttle.
Is the action complete?
—Verify repairGo to Step 7
7Replace the ECM (Refer to the Data Programming in
Case of ECM change).
Is the action complete?
—Verify repair—
Page 5577 of 6000

6E–148
4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1487 (Flash DTC 73)
Intake Throttle System Circuit Open/Start
060RW134
Circuit Description
The intake throttle position (ITP) sensor circuit provides a
voltage signal that changes relative to throttle blade
angle.
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 P1487 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 ITP
sensor. A change in the display will indicate the
location of the fault.
If DTC P1487 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
Page 5579 of 6000

6E–150
4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1488 (Flash DTC 72)
Intake Throttle Motor Control Circuit Signal Gap
060RW135
Circuit Description
The Intake throttle position (ITP) sensor circuit provides a
voltage signal that changes relative to throttle blade
angle.
Action Taken When the DTC Sets
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 P1488 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 ITP
sensor. A change in the display will indicate the
location of the fault.
If DTC P1488 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
Page 5580 of 6000

6E–151 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
DTC P1488 – Intake Throttle Motor Control Circuit Signal Gap
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
21. Ignition “ON,” engine “OFF.”
2. With the throttle closed, observe the “ITP Sensor”
display on the Tech 2.
Is the “ITP Sensor” below the specified value?
0.22 VGo to Step 4Go to Step 3
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 “Specific DTC” info for
DTC P1488.
Does the Tech 2 indicate DTC P1488 failed?
—Go to Step 4
Refer to
Diagnostic
Aids
4Check the ITP circuit for a poor connection at the ECM
and replace the terminal if necessary.
Did the terminal require replacement?
—Verify repairGo to Step 5
5Check the Intake throttle motor circuit for a poor
connection and replace the terminal if necessary.
Did the terminal require replacement?
—Verify repairGo to Step 6
6Check the ITP Assembly for a poor connection at the
TP sensor and fasten the ITP Assembly if necessary.
Did the ITP Assembly require repair?
—Verify repairGo to Step 7
7Replace the ECM (Refer to the Data Programming in
Case of ECM change).
Is the action complete?
—Verify repair—
Page 5584 of 6000

6E–155 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0510 (Flash DTC 75)
Idle SW Malfunction, Open Circuit
060RW134
Circuit Description
The idle switch signal is used by the Engine Control
Module ECM for fuel control.
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 P0510 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
Idle SW display on the Tech 2 while moving connectors
and wiring harnesses related to the Idle SW.
If DTC P0510 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
Page 5586 of 6000

6E–157 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1510 (Flash DTC 75)
Idle SW Malfunction Short Circuit
060RW134
Circuit Description
The idle switch signal is used by the Engine Control
Module ECM for fuel control.
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 P1510 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
Idle SW display on the Tech 2 while moving connectors
and wiring harnesses related to the Idle SW.
If DTC P0122 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
Page 5590 of 6000

6E–161 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1587 (Flash DTC 25)
Brake SW Malfunction
060RW130
Circuit Description
Brake Stop Lamp SW Circuit receives through Stop Lamp
10A fuse from the battery.
Action Taken When the DTC Sets
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 P1587 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
Brake SW display on the Tech 2 while moving
connectors and wiring harnesses related to the Brake
SW. A change in the display will indicate the location
of the fault.
If DTC P1587 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.
Page 5592 of 6000

6E–163 4JX1–TC ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1588 (Flash DTC 25)
Brake SW Malfunction
060RW130
Circuit Description
Brake Stop Lamp SW Circuit receives through Stop Lamp
10A fuse from the battery.
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 P1588 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
Brake SW display on the Tech 2 while moving
connectors and wiring harnesses related to the Brake
SW. A change in the display will indicate the location
of the fault.
If DTC P1588 cannot be duplicated, the information
included in the Failure Records data can be useful in
determining vehicle mileage since the DTC was last set.