Test Procedure

HU1 CHECK FOR DIAGNOSTIC TROUBLE CODES (DTCS)

Are DTCs P0505, P0506, P0660, P0663, P1512, P1513, P1516, P1517, P1518, P1519, P151A, P1520, P1537, P1538, P1549, P2004, P2005, P2006, P2007, P2008, P2014, P2015, P2019, P2020, P2070, or P2071 present?

Yes	No
For DTCs P0505 or P0506, on vehicles with electronic throttle control (ETC), GO to HU51. For DTCs P0505 or P0506, on vehicles without ETC, GO to HU2. For DTCs P0660, P0663, P1549, P2070 or P2071, GO to HU42. For DTCs P1512, P1513, P1516, P1517, P1518, P1519, P1520, P1537, P1538, P2004, P2005, P2006, P2007, P2008, P2014, P2015, P2019 or P2020, GO to HU15. For DTC P151A, Mustang 4.6L, Explorer 4.6L, Explorer Sport Trac 4.6L, and Mountaineer 4.6L. GO to HU18. For DTC P151A, all others, GO to HU17.	For vehicles equipped with electronic throttle control (ETC) that have low idle concerns, difficulty starting, hesitation, loss of RPM, GO to HU51. For lack/loss of power, GO to HU42. For all other symptoms without DTCs, GO to HU2.

Yes

For DTCs P0505 or P0506, on vehicles with electronic throttle control (ETC),
GO to HU51.
For DTCs P0505 or P0506, on vehicles without ETC,
GO to HU2.
For DTCs P0660, P0663, P1549, P2070 or P2071, GO to HU42.
For DTCs P1512, P1513, P1516, P1517, P1518, P1519, P1520, P1537, P1538, P2004, P2005, P2006, P2007, P2008, P2014, P2015, P2019 or P2020, GO to HU15.
For DTC P151A, Mustang 4.6L, Explorer 4.6L, Explorer Sport Trac 4.6L, and Mountaineer 4.6L.
GO to HU18.
For DTC P151A, all others,
GO to HU17.

For vehicles equipped with electronic throttle control (ETC) that have low idle concerns, difficulty starting, hesitation, loss of RPM, GO to HU51.
For lack/loss of power, GO to HU42.
For all other symptoms without DTCs, GO to HU2.

HU2 PART THROTTLE SYMPTOM

Are any part throttle concerns present?

Yes	No
GO to HU7.	GO to HU3.

HU3 CHECK THE BASE IDLE SPEED

NOTE: The vehicle must be at operating temperature and at idle for a minimum of 1 minute.

Ignition ON, engine running.
Determine if the idle speed is incorrect. Refer to the REFERENCE VALUES Typical Reference Value Charts, if necessary.
Access the PCM and monitor the RPM PID.
If equipped, read the vehicle tachometer.

Is vehicle idle speed correct?

Yes	No
GO to HU5.	GO to HU4.

HU4 CHECK THE THROTTLE ARM CONTACTS

Ignition OFF.
Check that the throttle arm contacts the return stop.
Ignition ON, engine running.

Is the idle speed high?

Yes	No
GO to HU9.	GO to HU10.

HU5 CHECK FOR BINDING OR STICKING IN THE THROTTLE SYSTEM

Gently cycle the throttle from fully closed to fully open and back to fully closed. Check for sticking or binding during rotation.

Is a stick and bind condition present?

Yes	No
GO to HU6.	GO to HU7.

HU6 ISOLATE THE BINDING AND/OR STICKING CONCERN

NOTE: Do not attempt to clean the throttle bore and plate area. Cleaning damages the throttle body assembly.

NOTE: The sticking or binding condition can either be within the cables or throttle body assembly.

Disconnect the accelerator cable and speed control cable from the throttle body linkage.
Rotate the throttle body linkage.

Does the throttle body rotate freely without a sticking, binding or grabbing condition?

Yes	No
REPAIR the cable(s) causing the concern. CLEAR the DTCs. REPEAT the self-test.	INSTALL a new throttle body assembly. REFER to the appropriate Fuel Charging And Controls article . CLEAR the DTCs. REPEAT the self-test.

HU7 CHECK THE FUNCTIONALITY OF THE THROTTLE POSITION (TP) SENSOR

Ignition ON, engine OFF.
Access the PCM and monitor the TP PID.
Gently cycle the throttle from fully closed to fully open and back to fully closed.

Does the TP PID display a smooth voltage reading?

Yes	No
GO to HU8.	INSTALL a new TP sensor. REFER to the appropriate Electronic Engine Controls article . CLEAR the DTCs. REPEAT the self-test.

HU8 CHECK THE INTAKE AIR SYSTEM FOR LEAKS, OBSTRUCTIONS AND DAMAGE

NOTE: The Focus air cleaner element is integral to the air cleaner assembly. Inspect the air restriction gauge (if equipped) for a restriction indication.

Ignition OFF.
Remove the air cleaner element. Check the air cleaner for blockage.
Check for restrictions between the air inlet and the throttle body.

Are any restriction concerns present?

Yes	No
REMOVE the restriction. INSTALL a new air cleaner element. REFER to the appropriate Intake Air Distribution And Filtering article . CLEAR the DTCs. REPEAT the self-test.	REINSTALL the air cleaner element. GO to HU9.

HU9 CHECK THE POSITIVE CRANKCASE VENTILATION (PCV) SYSTEM

NOTE: A high idle may indicate an incorrect PCV valve size or a vacuum leak.

Check that no cracks or leaks are present.
Remove the PCV valve.
- Verify a clean PCV valve.
- Verify the proper PCV valve part number.

Are any PCV system concerns present?

Yes	No
INSTALL a new PCV valve. REPAIR as necessary. REFER to the appropriate Engine Emission Controls article . CLEAR the DTCs. REPEAT the self-test.	For high idle, GO to HU13. For all others, CONNECT the PCV valve. GO to HU10.

HU10 CHECK THE IDLE AIR CONTROL (IAC) VALVE RESPONSE

Ignition ON, engine running.
The vehicle must be at operating temperature and at idle for a minimum of 1 minute.
IAC connector disconnected.

Does the RPM drop or the engine stall?

Yes	No
GO to HU12.	GO to HU11.

HU11 CHECK THE IAC VALVE RESPONSE

Is the idle speed high?

Yes	No
GO to HU13.	INSTALL a new IAC. REFER to the appropriate Electronic Engine Controls article . CLEAR the DTCs. REPEAT the self-test.

HU12 INSPECT THE THROTTLE BODY PLATE HOLE FOR PLUGGING

NOTE: Only some applications have a throttle plate hole. If not equipped go to SYMPTOM CHARTS - GASOLINE MODELS article .

Ignition OFF.
Remove the resonator from the throttle body assembly.
Inspect the throttle plate hole for any restrictions.

Are any restriction concerns present?

Yes	No
REPAIR as necessary. CLEAR the DTCs. REPEAT the self-test.	The concern is elsewhere. RETURN to NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT SYMPTOM CHART INDEX , to DIAGNOSE performance while driving concerns.

HU13 CHECK FOR VACUUM LEAKS

Listen for vacuum leaks.
Inspect the entire intake air system from the mass air flow (MAF) sensor to the intake manifold for leaks such as:
- cracked or punctured intake air tube.
- loose connections on the intake air tube at the air cleaner housing or throttle body
- IAC valve assembly or gasket
- EGR valve gasket leak to intake manifold
- intake manifold assembly or gasket
- EGR valve diaphragm or control solenoid
- vacuum supply connectors and hose

Are any leaks present?

Yes	No
REPAIR as necessary. CLEAR the DTCs. REPEAT the self-test.	GO to HU14.

HU14 CHECK THE THROTTLE BODY FOR EXCESSIVE WEAR

Ignition OFF.
Remove the throttle body assembly. Refer to the appropriate Fuel Chargine And Controls article for removal and inspection.
Check the following:
- excessive wear or grooving in the throttle bore
- misaligned or worn throttle plate
- excessive gap between the throttle bore and plate

Are any concerns present?

Yes	No
INSTALL a new throttle body assembly. REFER to the appropriate Fuel Charging And Controls article . CLEAR the DTCs. REPEAT the self-test.	The concern is elsewhere. RETURN to NO DIAGNOSTIC TROUBLE CODES (DTCS) PRESENT SYMPTOM CHART INDEX , to DIAGNOSE performance while driving concerns.

HU15 DTCS P1512, P1513, P1516, P1517, P1518, P1519, P1520, P1537, P1538, P2004, P2005, P2006, P2007, P2008, P2014, P2015, P2019 OR P2020: VISUAL INSPECTION

NOTE: If unable to fully carry out the following inspections, answer NO to the question in this step.

NOTE: The IMRC return spring is strong on vacuum systems. Make sure the vacuum system operates correctly and the plates open and close fully. On vacuum operated systems the engine must run for 20 seconds to restore vacuum then return to KOEO for testing.

Some IMRC electrical systems are driven in both directions by the solenoid and do not use a return spring. They can not be opened manually.

Visually inspect the linkage for possible causes of binding or obstructions. Check the lever/linkage for movement. There may be some tension in one direction but there should be full travel.
Manually open and close the IMRC plates at the intake manifold while checking for sticking or binding.

Is a mechanical concern present?

Yes	No
GO to HU16.	For Explorer 4.6L, Explorer Sport Trac 4.6L, Mountaineer 4.6L, Mustang 4.6L, and F-150 4.6L 3V, GO to HU18. For all others, GO to HU17.

HU16 CHECK THE IMRC FOR MECHANICAL OPERATION

NOTE: The IMRC return spring is strong - approximately 0.34 to 0.45 Nm (3 to 4 in-lb).

NOTE: Some electric motor applications do not use a return spring and should move freely when open and closed.

Disconnect the IMRC linkage or remove the actuator assembly from the manifold.
Rotate the IMRC plate lever to fully open and to fully closed, contacting both limits.
Check for sticking or binding during rotation.

Is a mechanical concern present?

Yes	No
REPAIR as necessary or INSTALL a new IMRC. REFER to the appropriate Engine article or appropriate Electronic Engine Controls article . CLEAR the DTCs. REPEAT the self-test.	CONNECT the IMRC linkage. For Explorer 4.6L, Explorer Sport Trac 4.6L, Mountaineer 4.6L, Mustang 4.6L, and F-150 4.6L 3V, GO to HU18. For all others, GO to HU17.

HU17 DTC P151A: CHECK THE FUNCTIONALITY OF THE IMRC

WARNING: KEEP FINGERS CLEAR OF THE MECHANISM. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.

NOTE: The vehicle must be at operating temperature and at idle for a minimum of 1 minute.

Ignition ON, engine running.
Access the PCM and monitor the IMRC1M PID.
Access the PCM and control the IMRC PID.
Command IMRC ON then OFF.
Refer to the following chart.

IMRCM VOLTAGE VALUES

VEHICLE	IMRC OFF	IMRC ON
Focus, 2.0L	0	5
F-150, 3V, 4.6L	5	0
All Others	2.5	0

Using the table for reference, do the IMRCM voltage values correctly change while the IMRC is cycled?

Yes	No
GO to Pinpoint Test Z .	GO to HU19.

HU18 CHECK THE FUNCTIONALITY OF BI-DIRECTIONAL IMRC

WARNING: KEEP FINGERS CLEAR OF THE MECHANISM. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.

NOTE: The vehicle must be at operating temperature and at idle for a minimum of 1 minute.

Ignition ON, engine running.
Access the PCM and monitor the IMRC_F PID.
Access the PCM and control the IMRC PID.
Command IMRC ON then OFF.

Do the IMRC values correctly change from off to on while the IMRC is cycled and is the IMRCF PID no?

Yes	No
GO to Pinpoint Test Z .	GO to HU19.

HU19 CHECK THE FUNCTIONALITY OF THE IMRC

WARNING: KEEP FINGERS CLEAR OF THE MECHANISM. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.

NOTE: The vehicle must be at operating temperature and at idle for a minimum of 1 minute.

Ignition ON, engine running.
Physically monitor the IMRC actuator.
Access the PCM and control the IMRC PID.
Command the outputs ON.

Do the IMRC levers cycle from fully closed and remain fully open while the outputs are on?

Yes	No
GO to HU28.	GO to HU20.

HU20 CHECK THE VPWR CIRCUIT FOR AN OPEN IN THE HARNESS

Ignition OFF.
IMRC Actuator connector disconnected.
Ignition ON, engine OFF.
Measure the voltage between:

(+) IMRC Actuator Connector, Harness Side	(-)
VPWR	Ground

Is the voltage greater than 10 V?

Yes	No
GO to HU21.	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

HU21 CHECK THE GROUND CIRCUIT FOR AN OPEN IN THE HARNESS

Measure the voltage between:

(+) IMRC Actuator Connector, Harness Side	(-) IMRC Actuator Connector, Harness Side
VPWR	PWRGND

Is the voltage greater than 10 V?

Yes	No
GO to HU22.	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

HU22 VERIFY THE DRIVER CIRCUIT FUNCTION

Connect a non-powered test lamp between:

Point A IMRC Actuator Connector, Harness Side	Point B IMRC Actuator Connector, Harness Side
VPWR	IMRC

Does the test lamp illuminate?

Yes	No
GO to HU27.	GO to HU23.

HU23 VERIFY THE DRIVER CIRCUIT FUNCTION WHILE COMMANDING ON IMRC

Ignition ON, engine running.
Access the PCM and control the IMRC PID.
Connect a non-powered test lamp between:

Point A IMRC Actuator Connector, Harness Side	Point B IMRC Actuator Connector, Harness Side
VPWR	IMRC

Command the outputs ON.

Does the test lamp illuminate?

Yes	No
GO to HU26.	GO to HU24.

HU24 CHECK THE IMRC CIRCUIT FOR AN OPEN IN THE HARNESS

Ignition OFF.
PCM connector disconnected.
Measure the resistance between:

(+) IMRC Actuator Connector, Harness Side	(-) PCM Connector, Harness Side
IMRC	IMRC

Is the resistance less than 5 ohms?

Yes	No
GO to HU25.	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

HU25 CHECK THE IMRC CIRCUIT FOR A SHORT TO VPWR IN THE HARNESS

Ignition ON, engine OFF.
Measure the voltage between:

(+) IMRC Actuator Connector, Harness Side	(-)
IMRC	Ground

Is the voltage less than 10 V?

Yes	No
GO to HU53.	REPAIR the short circuit to voltage. CLEAR the DTCs. REPEAT the self-test.

HU26 CHECK FOR SHORTS BETWEEN CIRCUITS IN THE IMRC HARNESS

Ignition OFF.
PCM connector connected.
Measure the resistance between:

(+) IMRC Actuator Connector, Harness Side	(-) IMRC Actuator Connector, Harness Side
IMRC	IMRCM
IMRC	PWRGND

Are the resistances greater than 10K ohms?

Yes	No
INSTALL a new IMRC actuator. REFER to the appropriate Engine article or appropriate Electronic Engine Controls article as necessary. CLEAR the DTCs. REPEAT the self-test.	GO to HU27.

HU27 CHECK FOR SHORTS BETWEEN CIRCUITS IN THE IMRC HARNESS

PCM connector disconnected.
Measure the resistance between:

(+) IMRC Actuator Connector, Harness Side	(-) IMRC Actuator Connector, Harness Side
IMRC	IMRCM
IMRC	PWRGND

Are the resistances greater than 10K ohms?

Yes	No
GO to HU53.	REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test. GO to HU41.

HU28 CHECK THE IMRCM PID

Ignition ON, engine OFF.
Access the PCM and monitor the IMRC1M PID.

Is the IMRCM PID displaying either VREF or approximately 2.5 volts?

Yes	No
GO to HU29.	GO to HU33.

HU29 CHECK THE IMRCM CIRCUIT FOR A SHORT TO VPWR

NOTE: The vehicle must be at operating temperature and at idle for a minimum of 1 minute.

Ignition ON, engine running.
Access the PCM and control the IMRC PID.
Command the outputs ON.
Access the PCM and monitor the IMRC1M PID.

Is the voltage less than 1 V?

Yes	No
GO to HU30.	GO to HU35.

HU30 CHECK THE IMRCM CIRCUIT FOR A SHORT TO VPWR IN THE HARNESS

Ignition ON, engine OFF.
IMRCM Sensor connector disconnected.
Measure the voltage between:

(+) IMRCM Sensor Connector, Harness Side	(-)
IMRCM	Ground

Is the voltage greater than 10 V?

Yes	No
GO to HU31.	GO to HU32.

HU31 CHECK THE IMRCM CIRCUIT FOR A SHORT TO VOLTAGE IN THE CONTROL MODULE

PCM connector disconnected.
Ignition ON, engine OFF.
Measure the voltage between:

(+) IMRCM Sensor Connector, Harness Side	(-)
IMRCM	Ground

Is the voltage greater than 10 V?

Yes	No
REPAIR the short circuit to voltage. CLEAR the DTCs. REPEAT the self-test.	GO to HU53.

HU32 CHECK THE IMRCM CIRCUIT FOR A SHORT TO VPWR

Ignition OFF.
Measure the resistance between:

(+) IMRCM Sensor Connector, Component Side	(-) IMRCM Sensor Connector, Component Side
IMRCM	VPWR

Is the resistance greater than 10K ohms?

Yes	No
CHECK for an intermittent concern. GO to Pinpoint Test Z .	INSTALL a new IMRCM sensor. REFER to the appropriate Engine article or appropriate Electronic Engine Controls article as necessary. CLEAR the DTCs. REPEAT the self-test. GO to HU41.

HU33 CHECK THE IMRCM CIRCUIT FOR A SHORT TO GROUND

Ignition ON, engine OFF.
Access the PCM and monitor the IMRC1M PID.
IMRCM Sensor connector disconnected.

Does voltage change from less than 1 volt to VREF when disconnecting the IMRCM harness connector?

Yes	No
INSTALL a new IMRCM sensor. REFER to the appropriate Engine article or appropriate Electronic Engine Controls article as necessary. CLEAR the DTCs. REPEAT the self-test. GO to HU41.	GO to HU34.

HU34 CHECK THE IMRCM CIRCUIT(S) FOR A SHORT TO GROUND IN THE HARNESS

PCM connector disconnected.
Measure the resistance between:

(+) IMRCM Sensor Connector, Harness Side	(-) IMRCM Sensor Connector, Harness Side
IMRCM	PWRGND

Is the resistance greater than 10K ohms?

Yes	No
GO to HU53.	REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test. GO to HU41.

HU35 CHECK THE MONITOR CIRCUIT RESPONSE

IMRCM Sensor connector disconnected.
Access the PCM and monitor the IMRC1M PID.
Connect a 5 amp fused jumper wire between the following:

Point A IMRCM Sensor Connector, Harness Side	Point B
IMRCM	Ground

Does voltage change from less than 1 volt to VREF when disconnecting the IMRCM harness connector?

Yes	No
GO to HU36.	GO to HU39.

HU36 CHECK THE PWRGND CIRCUIT FOR CONTINUITY TO CHASSIS GND

Ignition OFF.
Remove the jumper wire(s).
PCM connector connected.
Measure the resistance between:

(+) IMRCM Sensor Connector, Harness Side	(-) Vehicle Battery
PWRGND	Negative terminal

Is the resistance less than 5 ohms?

Yes	No
GO to HU37.	GO to HU38.

HU37 CHECK THE MONITOR CIRCUIT FOR AN INTERMITTENT OPEN

PCM connector disconnected.
Measure the resistance between:

(+) IMRCM Sensor Connector, Harness Side	(-) PCM Connector, Harness Side
IMRCM	IMRCM

Wiggle, shake, and bend small sections of the wiring harness while working from the component to the module.

Is the resistance fluctuating while checking the harness?

Yes	No
REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test. GO to HU41.	INSTALL a new IMRCM sensor. REFER to the appropriate Engine article or appropriate Electronic Engine Controls article as necessary. CLEAR the DTCs. REPEAT the self-test. GO to HU41.

HU38 CHECK THE HARNESS PWRGND CIRCUIT FOR CONTINUITY

PCM connector disconnected.
Measure the resistance between:

(+) IMRCM Sensor Connector, Harness Side	(-) PCM Connector, Harness Side
PWRGND	PWRGND

Is the resistance less than 5 ohms?

Yes	No
CHECK the circuit for an intermittent concern. GO to Pinpoint Test Z .	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test. GO to HU41.

HU39 CHECK THE IMRCM CIRCUIT FOR AN OPEN IN THE HARNESS

Ignition OFF.
Remove the jumper wire(s).
PCM connector disconnected.
Measure the resistance between:

(+) IMRCM Sensor Connector, Harness Side	(-) PCM Connector, Harness Side
IMRCM	IMRCM

Is the resistance less than 5 ohms?

Yes	No
GO to HU40.	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test. GO to HU41.

HU40 CHECK THE MONITOR CIRCUIT FOR AN INTERMITTENT OPEN

Measure the resistance between:

(+) IMRCM Sensor Connector, Harness Side	(-) PCM Connector, Harness Side
IMRCM	IMRCM

Wiggle, shake, and bend small sections of the wiring harness while working from the component to the module.

Is the resistance fluctuating while checking the harness?

Yes	No
REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test. GO to HU41.	GO to HU53.

HU41 VERIFY THE REPAIR

Ignition ON, engine OFF.
Clear the PCM DTCs.
Access the PCM and monitor the IMRC and IMRC_F PIDs.
Access the PCM and monitor the IMRC1M PID.
Ignition ON, engine running.
Drive the vehicle, obeying all traffic and safety laws.
Safely carry out 3 acceleration runs from a stop or roll to between 3,000 and 4,000 RPM.
Watch for any PID change.
Carry out the PCM self-test.

Are any DTCs received?

Yes	No
DISREGARD the current diagnostic trouble code (DTC) at this time. DIAGNOSE the next DTC. GO to DTC LIST .	The test completed successfully.

HU42 DTCS P0660, P0663, P1549, P2070 OR P2071: VISUAL INSPECTION OF THE INTAKE MANIFOLD TUNING VALVE

Inspect the component for signs of damage.
Check the harness and connection.

Is a concern present?

Yes	No
REPAIR as necessary. CLEAR the DTCs. REPEAT the self-test.	GO to HU43.

HU43 CHECK THE VPWR CIRCUIT FOR AN OPEN IN THE HARNESS

IMTV Actuator connector disconnected.
Ignition ON, engine OFF.
Measure the voltage between:

(+) IMTV Actuator Connector, Harness Side	(-) Vehicle Battery
VPWR	Negative terminal

Is the voltage greater than 10.5 V?

Yes	No
GO to HU44.	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

HU44 CHECK THE IMTV CIRCUIT FOR AN OPEN IN THE HARNESS

Ignition OFF.
PCM connector disconnected.
Measure the resistance between:

(+) IMTV Actuator Connector, Harness Side	(-) PCM Connector, Harness Side
IMTV	IMTV

Is the resistance less than 5 ohms?

Yes	No
GO to HU45.	REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

HU45 CHECK THE IMTV CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS

Measure the resistance between:

(+) PCM Connector, Harness Side	(-)
IMTV	Ground

Is the resistance greater than 10K ohms?

Yes	No
GO to HU46.	REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test.

HU46 CHECK THE IMTV CIRCUIT FOR A SHORT TO VPWR IN THE HARNESS

Measure the voltage between:

(+) PCM Connector, Harness Side	(-)
IMTV	Ground

Is the voltage less than 1 V?

Yes	No
GO to HU47.	REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test.

HU47 CHECK THE IMTV DRIVER CIRCUIT WITH THE PCM CONNECTED

IMTV Actuator connector disconnected.
PCM connector connected.
Ignition ON, engine OFF.
Connect a non-powered test lamp between:

Point A IMTV Actuator Connector, Harness Side	Point B IMTV Actuator Connector, Harness Side
VPWR	IMTV

Does the test lamp illuminate?

Yes	No
GO to HU53.	GO to HU48.

HU48 CHECK THE IMTV PCM DRIVER CIRCUIT WHEN COMMANDED ON

Access the PCM and control the IMTV PID.
Connect a non-powered test lamp between:

Point A IMTV Actuator Connector, Harness Side	Point B IMTV Actuator Connector, Harness Side
VPWR	IMTV

Does the test lamp illuminate?

Yes	No
GO to HU49.	GO to HU53.

HU49 CHECK THE IMTV FOR DAMAGE

Ignition OFF.
Remove the IMTV. Refer to the appropriate Engine article or Electronic Engine Controls article .
Visually inspect the shutter for damage.
Manually rotate the shutter.

Is a concern present?

Yes	No
INSTALL a new IMTV actuator. REFER to the appropriate Engine or appropriate Electronic Engine Controls article as necessary. CLEAR the DTCs. REPEAT the self-test.	GO to HU50.

HU50 CHECK THE IMTV FOR FUNCTIONALITY WHEN COMMANDED ON

IMTV Actuator connector connected.
Ignition ON, engine OFF.
Access the PCM and control the IMTV PID.

Does the IMTV shutter rotate?

Yes	No
The concern is an intermittent. GO to Pinpoint Test Z .	INSTALL a new IMTV actuator. REFER to the appropriate Engine article or appropriate Electronic Engine Controls article as necessary. CLEAR the DTCs. REPEAT the self-test.

HU51 PRELIMINARY DIAGNOSIS FOR DIAGNOSTIC TROUBLE CODES (DTCS) P0505 OR P0506

Ignition ON, engine OFF.

Are any DTCs present other than P0505 or P0506?

Yes	No
DISREGARD the current diagnostic trouble code (DTC) at this time. DIAGNOSE the next DTC. GO to DTC LIST .	GO to HU52.

HU52 MONITOR THE INTAKE AIR SYSTEM RELATED PIDS

NOTE: Verify that the vehicle has reached the normal engine coolant operating temperature of 77°C (170°F). Allow the engine to idle an additional 5 minutes.

NOTE: The ETC_TRIM PID may not be available on all vehicles.

Access the PCM and monitor the ECT PID.
Access the PCM and monitor the ETC_TRIM PID.
Access the PCM and monitor the IACTRIM and IACKAM2 PIDs.
Mathematically add and record the value of the IACTRIM PID to the IACKAM2 PID value, for the total IAC value at idle.

Is the ETC_TRIM PID angle equal to 3.5 degrees or is the total IAC value greater than 0.5 lb/min?

Yes	No
INSTALL a new throttle body assembly. REFER to the appropriate Fuel Charging And Controls article to INSTALL a new throttle body. CLEAR the DTCs. REPEAT the self-test.	RETURN to SYMPTOM CHARTS - GASOLINE MODELS article for further direction.

HU53 CHECK FOR CORRECT PCM OPERATION

Disconnect all the PCM connectors.
Visually inspect for:
- pushed out pins
- corrosion
Connect all the PCM connectors and make sure they seat correctly.
Carry out the PCM self-test and verify the concern is still present.

Is the concern still present?

Yes	No
INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) , Programming the VID Block for a Replacement PCM.	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.