ENGINE CONTROL SYSTEM OPERATION INSPECTION [LF, L5]


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Input Signal System Inspection Procedure

1.  Find an irregular signal. (See Finding irregular signals.)

2.  Locate source. (See Locating the source of unusual signals.)

3.  Repair or replace the malfunctioning part.

4.  Confirm that the irregular signal is no longer detected.


Finding irregular signals

While referring to ON-BOARD DIAGNOSTIC TEST [LF, L5], use the PID/DATA monitor and record function to inspect the input signal system relating to the problem.

1.  Start the engine and idle the vehicle. You can assume that any signals that are out of specification by a wide margin are irregular.

2.  When recreating the problem, any sudden change in monitor input signals that is not intentionally created by the driver can be determined as irregular.


Locating the source of unusual signals

Caution
•  Compare the M-MDS monitor voltage with the measurement voltage using the digital measurement system function. If you use another tester, misreading may occur.
•  When measuring voltage, attach the tester ground to the ground of the PCM that is being tested, or to the engine itself. If this is not performed, the measured voltage and actual voltage may differ.
•  After connecting the pin to a waterproof coupler, confirming continuity and measuring the voltage, inspect the waterproof connector for cracks. If there are any, use sealant to fix them. Failure to do this may result in deterioration of the wiring harness or terminal from water damage, leading to problems with the vehicle.


Variable resistance type 1 (TP sensor and EGR valve)

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Input signal system inspection for variable resistance type 1

1.  When an irregular signal is detected, measure the #1 PCM terminal voltage.

•  If the #1 terminal voltage and the M-MDS monitor voltage are the same, proceed to the next step.
•  If there is a difference of 0.5 V or more, inspect for the following points concerning the PCM connector:
―  Female terminal opening is loose
―  Coupler (pin holder) damage
―  Pin discoloration (blackness)
―  Harness/pin crimp is loose or disconnected

2.  Measure the #2 sensor terminal voltage.

•  If there is a 0.5 V or more difference between the sensor and the M-MDS voltages, inspect the wiring harness for open or short circuits.
•  If the sensor and the M-MDS voltages are the same, inspect for the following points concerning the sensor connector:
―  Female terminal opening is loose
―  Coupler (pin holder) damage
―  Pin discoloration (blackness)
•  If there are no problems, proceed to next investigation below


Standard power supply system inspection for variable resistance type 1

•  Confirm that the #3 terminal is at 5 V.
―  If the measured voltage on the #3 terminal is 5 V, inspect the following points on the sensor connector.
―  If there is no problem, inspect for the following:
•  Female terminal opening is loose.
•  Coupler (pin holder) damage
•  Pin discoloration (blackness)
―  If the #3 terminal measures other than 5 V, inspect for the following:
•  Open or short circuit in wiring harness
•  Harness/pin crimp is loose or disconnected


GND system inspection for variable resistance type 1

•  Confirm that terminal sensor #5 is at 0 V.
―  If it is at 0 V, inspect the sensor.
•  If necessary, replace the sensor.
―  If not, inspect for the following:
•  Open or short circuit in wiring harness
•  Female terminal opening is loose causing an open or short circuit in wiring harness
•  Coupler (pin holder) damage
•  Pin discoloration (blackness)
•  Harness/pin crimp is loose or disconnected.


Variable resistance type 2 (Mass air flow (MAF) sensor and VSS)

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GND system inspection for variable resistance type 2

•  Confirm that terminal sensor #4 is at 0 V.
―  If it is at 0 V, inspect the sensor.
•  If necessary, replace the sensor.
―  If not at 0 V, inspect for the following:
•  Open circuit in wiring harness
•  Female terminal opening is loose
•  Coupler (pin holder) damage
•  Pin discoloration (blackness)
•  Harness/pin crimp is loose or disconnected.


Input signal system inspection for variable resistance type 2

1.  When an irregular signal is detected, measure the #1 PCM terminal voltage.

•  If the #1 terminal voltage and the M-MDS monitor voltage are the same, proceed to the next step.
•  If there is a difference of 0.5 V or more, inspect for the following points concerning the PCM connector:
―  Female terminal opening is loose
―  Coupler (pin holder) damage
―  Pin discoloration (blackness)
―  Harness/pin crimp is loose or disconnected

2.  Measure the #2 sensor terminal voltage.

•  If there is a 0.5 V or more difference between the sensor and the M-MDS voltages, inspect the wiring harness for open or short circuits.
•  If the sensor and the M-MDS voltages are the same, inspect the following points concerning the sensor connector:
―  Female terminal opening is loose
―  Coupler (pin holder) damage
―  Pin discoloration (blackness)
―  Harness/pin crimp is loose or disconnected
•  If there are no problems, proceed to next investigation below.


Electrical supply system inspection for variable resistance type 2

•  Confirm that the sensor #3 terminal is B+.
―  If the measured voltage on the #3 terminal is B+, inspect the following points on the sensor connector.
―  If there is no problem, inspect for the following:
•  Female terminal opening is loose
•  Coupler (pin holder) damage
•  Pin discoloration (blackness)
―  If the #3 terminal measures other than B+, inspect the following:
•  Open or short circuit in wiring harness
•  Harness/pin crimp is loose or disconnected


Thermistor type (IAT sensor and ECT sensor)

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Input signal system inspection for thermistor type

1.  When an irregular signal is detected, measure the #1 PCM terminal voltage.

•  If the #1 terminal voltage and the M-MDS monitor voltage are the same, proceed to the next step.
•  If there is a difference of 0.5 V or more, inspect the following points concerning the PCM connector:
―  Female terminal opening loose
―  Coupler (pin holder) damage
―  Pin discoloration (blackness)
―  Harness/pin crimp is loose or disconnected

2.  Measure the #2 sensor terminal voltage.

•  If there is a 0.5 V or more difference between the sensor and the M-MDS voltages, inspect the wiring harness for open or short circuits.
•  If the sensor and the M-MDS voltages are the same, inspect the following points concerning the sensor connector:
―  Female terminal opening is loose
―  Coupler (pin holder) damage
―  Pin discoloration (blackness)
―  Harness/pin crimp is loose or disconnected
•  If there are no problems, proceed to next investigation below.


GND system inspection for thermistor type

•  Confirm that terminal sensor #3 is at 0 V.
―  If it is at 0 V, inspect the sensor. If necessary, replace the sensor.
―  If not, inspect for the following:
•  Open circuit in wiring harness
•  Female terminal opening is loose
•  Coupler (pin holder) damage
•  Pin discoloration (blackness)
•  Harness/pin crimp is loose or disconnected


Main Relay Operation Inspection

1.  Verify that the main relay clicks when the ignition to ON and off.

•  If there is no operation sound, inspect the following:
―  Main relay (See RELAY INSPECTION.)
―  Harness and connector between ignition switch and main relay
―  Harness and connector between PCM terminal 1Q and main relay
―  Advanced keyless entry and push button start system operation (with advanced keyless entry and push button start). (See SYMPTOM TROUBLESHOOTING CHART [ADVANCED KEYLESS ENTRY AND PUSH BUTTON START SYSTEM].)


Intake Manifold Vacuum Inspection

1.  Verify air intake hoses are installed properly.

2.  Start the engine and run it at idle.

3.  Disconnect the vacuum hose between the intake manifold and purge solenoid valve from the intake manifold side.

4.  Connect a vacuum gauge to the intake manifold and measure the intake manifold vacuum.

•  If not as specified, inspect the following:
Specification
More than 60 kPa {450 mmHg, 18 inHg}
Note
•  Air suction can be located by engine speed change when lubricant is sprayed on the area where suction is occurring.
―  Air suction at throttle body, intake manifold and PCV valve installation points
―  EGR valve (stuck open)
―  Fuel injector insulator
―  Engine compression (See COMPRESSION INSPECTION [LF, L5].)


Electronic Throttle Control System Inspection


Engine coolant temperature compensation inspection

1.  Connect the M-MDS to the DLC-2.

2.  Access the following PIDs:

•  ECT
•  IAT
•  RPM

3.  Verify that the engine is cold, then start the engine.

4.  Verify that the engine speed decreases as the engine warms up.

•  If the engine speed does not decrease or decreases slowly, inspect the following:
―  ECT sensor and related wiring harness (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [LF, L5].)
―  Electronic throttle body and related wiring harness


Load compensation inspection

1.  Start the engine and idle it.

2.  Connect the M-MDS to the DLC-2.

3.  Verify that P0506:00 or P0507:00 is not displayed.

•  If P0506:00 or P0507:00 are displayed, perform DTC inspection. (See DTC P0506:00 [LF, L5].) (See DTC P0507:00 [LF, L5].)

4.  Access the RPM PID.

Note
•  Excludes temporary idle speed drop just after the loads are turned on.

5.  Verify that the engine speed is within the specification under each load condition.

•  If load condition is not as specified, inspect the following:
―  A/C switch and related wiring harness (See CLIMATE CONTROL UNIT INSPECTION [FULL-AUTO AIR CONDITIONER].)
―  Fan switch and related wiring harness (See CLIMATE CONTROL UNIT INSPECTION [FULL-AUTO AIR CONDITIONER].)


Except for Israel

Idle-up speed (MTX: Neutral position, ATX: P, N position)
A/C on: 700—800 rpm (MTX), 650—770 rpm (ATX)
Electrical loads on: 650—800 rpm


Israel

Idle-up speed (ATX: P, N position)
A/C on: 650—850 rpm (ATX)
Electrical loads on: 650—800 rpm


Throttle position (TP) sweep inspection

1.  Connect the M-MDS to the DLC-2.

2.  Switch the ignition to ON.

3.  Verify that none of the following DTC are displayed:

•  P0122:00, P0123:00, P0222:00, P0223:00, P0638:00, P2100:00, P2101:00, P2107:00, P2108:00, P2119:00, P2122:00, P2123:00, P2127:00, P2128:00, P2135:00, P2138:00
―  If any one DTC is displayed, perform DTC inspection. (See DTC TABLE [LF, L5].)

4.  Access TP REL PID.

5.  Verify that the PID reading is within the TP REL value. (See PCM INSPECTION [LF, L5].)

•  If the PID reading is out of range, perform the following:
―  Remove the air duct from the throttle body.
―  Verify that the throttle valve opens when the accelerator pedal is depressed.
•  If the throttle valve opens, inspect the TP sensor and related wiring harness. (See THROTTLE POSITION (TP) SENSOR INSPECTION [LF, L5].)
•  If the throttle valve does not open, inspect the throttle valve actuator control motor and related wiring harness.

6.  Gradually depress the throttle pedal and verify that the PID reading increases accordingly.

•  If the PID reading drops momentarily, inspect the following:

7.  Fully depress the throttle pedal and verify that the PID reading is within WOT value. (See PCM INSPECTION [LF, L5].)

•  If the PID reading is out of range, perform the followings:
―  Remove the air duct from throttle valve body.
―  Verify that the throttle valve opens when throttle pedal is depressed.
•  If the throttle valve opens, inspect the TP sensor and related wiring harness.
•  If the throttle valve does not open, inspect the throttle valve actuator control motor and related wiring harness.


Variable Intake air Control Operation Inspection

1.  Start the engine.

2.  Inspect the rod operation under the following condition:

Rod operation

Engine speed
4,600 rpm (LF), 4,300 rpm (L5)
Below
Above
Shutter valve actuator
Operate
Not operate

•  If the rod operation is not as specified, inspect as follows:
(1)  Stop the engine.
(2)  Connect the M-MDS to the DLC-2.
(3)  Verify that DTC P0661:00 or P0662:00 is not displayed.
•  If DTC P0661:00 or P0662:00 is shown, perform DTC inspection. (See DTC P0661:00 [LF, L5].) (See DTC P0662:00 [LF, L5].)
(4)  Inspect the variable intake air solenoid valve. (See VARIABLE INTAKE AIR SOLENOID VALVE INSPECTION [LF, L5].)
•  If the variable intake air solenoid valve is not normal, replace the variable intake air solenoid valve. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF, L5].)
•  If the variable intake air solenoid valve is normal, inspect the following:
―  Vacuum hose and vacuum chamber for looseness or damage
―  Shutter valve stuck open or closed


Brake override system operation inspection (From BL****-198281,BL1***-239890)

Note
•  If the brake override system operates normally after performing the following inspection, the PCM detects DTC P2299.

1.  Start the engine and run it is idling.

2.  Verify that the engine speed becomes approx. 1,200 rpm under the following conditions.

•  Neutral (MTX)
•  P, or N position (ATX)
•  Engine speed of 1,150 rpm or more other than idle
•  Brake pedal depressed

•  If the engine speed becomes approx. 1,200 rpm, clear the PCM DTC using the M-MDS. (System operation is normal.)
•  If the engine speed does not become approx. 1,200 rpm, inspect for the following parts, then repair or replace the malfunctioning part:
―  Neutral switch (MTX)
―  Brake switch


Variable Tumble Control Operation Inspection

1.  Connect the M-MDS to the DLC-2.

2.  Access ECT PID.

3.  Verify that ECT PID is between 63 °C {145 °F} and 67 °C {153 °F}.

4.  Start the engine.

5.  Inspect rod operation under the following conditions:

Rod operation

Engine speed
3,750 rpm
Below
Above
Shutter valve actuator
Operate
Not operate

•  If the rod operation is not specified, inspect as follows:
(1)  Verify that DTC P2009:00 or P2010:00 is not displayed.
•  If DTC No. P2009:00 or P2010:00 are shown, perform DTC inspection. (See DTC P2009:00 [LF, L5].) (See DTC P2010:00 [LF, L5].)
(2)  Inspect the variable tumble solenoid valve. (See VARIABLE TUMBLE SOLENOID VALVE INSPECTION [LF, L5].)
•  If the variable tumble solenoid valve is not normal, replace the variable tumble solenoid valve. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF, L5].)
•  If the variable tumble solenoid valve is normal, inspect the following:
―  Vacuum hose and vacuum chamber for looseness or damage
―  Shutter valve stuck open or closed


Fuel Injector Operation Inspection

If simulation function of M-MDS is used:

STEP

INSPECTION

RESULTS

ACTION

1
Start the engine and warm it up until normal operating temperature.
Connect the M-MDS to the DLC-2.
Select the INJ_1, INJ_2, INJ_3 and INJ_4 PIDs.
Turn the fuel injector from on to off using the M-MDS simulation function for each cylinder.
Does the engine speed drop?
Yes
Fuel injector operation is normal.
No
Go to the next step.
2
Disconnect the fuel injector connector that the engine speed does not drop at Step 1.
Switch the ignition to ON.
Measure the voltage between suspected fuel injector terminal B (wiring harness-side) and body ground.
Is the voltage B+?
Yes
Go to the next step.
No
Repair or replace for open or short circuit between fuel injector terminal B and main relay terminal C.
3
Inspect for open or short circuit between suspected fuel injector terminal A (wiring harness-side) and following PCM terminals:
•  Fuel injector No.1 terminal A—PCM terminal 2BB
•  Fuel injector No.2 terminal A—PCM terminal 2BC
•  Fuel injector No.3 terminal A—PCM terminal 2BD
•  Fuel injector No.4 terminal A—PCM terminal 2AZ
Is there any malfunction?
Yes
Repair or replace the wiring harness for a possible open or short circuit.
No
Go to the next step.
4
Inspect the suspected fuel injector.
Is there any malfunction?
Yes
Replace the suspected fuel injector.
No
Replace the PCM.

If simulation function of M-MDS is not used:

STEP

INSPECTION

RESULTS

ACTION

1
While cranking the engine, inspect for fuel injector operation sound at each cylinder using a soundscope.
Is the operation sound heard?
Yes
Fuel injector operation is normal.
No
All cylinders not heard:
•  Go to the next step.
Some cylinders not heard:
•  Go to Step 3.
2
Perform the Main Relay Operation Inspection.
Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Inspect the following:
•  Fuel injector power system related wiring harness and connectors
•  PCM connectors
•  Fuel injector GND and related wiring harness and connectors
Repair or replace the malfunctioning part according to the inspection results.
3
Switch the fuel injector connector of not operating fuel injector with operating fuel injector.
Is the operation sound heard?
Yes
Go to the next step.
No
Replace the suspected fuel injector.
4
Inspect the wiring harness and connectors of suspected fuel injector (Open or short).
•  Fuel injector No.1 terminal A—PCM terminal 2BB
•  Fuel injector No.2 terminal A—PCM terminal 2BC
•  Fuel injector No.3 terminal A—PCM terminal 2BD
•  Fuel injector No.4 terminal A—PCM terminal 2AZ
Is there any malfunction?
Yes
Repair or replace the malfunctioning part according to the inspection results.
No
Replace the PCM.


Fuel Cut Control System Inspection

1.  Warm up engine and idle it.

2.  Turn off the electrical loads and A/C switch.

3.  Connect the M-MDS to the DLC-2.

4.  Access RPM PID.

5.  Listen for the fuel injector operation sound at all cylinders using the soundscope and monitor both PIDs while performing the following steps:

(1)  Depress the accelerator pedal and increase the engine speed to 4,000 rpm.
(2)  Quickly release the accelerator pedal (brake pedal is not depressed) and verify that the fuel injector operation sound stops, and starts again when the engine speed drops below 1,200 rpm.
•  If not as specified, inspect the following:
―  ECT sensor and related wiring harness (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [LF, L5].)
―  Neutral/clutch pedal position switch and related wiring harness (MTX) (See NEUTRAL SWITCH INSPECTION [LF, L5].) (See CLUTCH PEDAL POSITION (CPP) SWITCH INSPECTION [LF, L5].)
―  TR switch and related wiring harness (ATX) (See TRANSAXLE RANGE (TR) SWITCH INSPECTION [FS5A-EL].)


Fuel Pump Operation Inspection

1.  Remove the fuel-filler cap.

2.  Switch the ignition to ON.

3.  Turn the fuel pump relay from off to on using the FP PID and inspect if the operation sound is heard.

•  If no operation sounds is heard, proceed to next step.

4.  Measure voltage at wiring harness side fuel pump unit connector terminal B.

Specification
B+ (Ignition at on)
•  If the voltage is as specified, inspect the following:
―  Fuel pump continuity
―  Fuel pump GND
―  Wiring harness between fuel pump relay and PCM terminal 1BG (with immobilizer system)/1BH (without immobilizer system)
•  If not as specified, inspect the following:
―  Fuel pump relay
―  Wiring harness connector (Main relay—Fuel pump relay—Fuel pump unit)


Fuel Pump Control System Inspection

1.  Crank the engine and verify that fuel pump relay operation sound is heard.

2.  If operation sound is not heard, inspect the following:

•  Fuel pump relay (See RELAY INSPECTION.)
•  Wiring harness and connectors (Main relay—Fuel pump relay—PCM terminal 1BG (with immobilizer system)/1BH (without immobilizer system))


Spark Test

1.  Disconnect the fuel pump relay.

2.  Verify that each ignition coil and connector is connected properly.

3.  Inspect the ignition system in the following procedure.

Warning
•  High voltage in the ignition system can cause strong electrical shock which can result in serious injury. Avoid direct contact to the vehicle body during the following spark test.

STEP

INSPECTION

ACTION

1
•  Disconnect the ignition coil from the spark plugs.
•  Remove the spark plugs.
•  Verify that the spark plugs do not have carbon deposits.
•  Are the spark plugs normal?
Yes
Go to the next step.
No
Perform no-load racing at 4,000 rpm for 2 min, 2 times to burn off the carbon deposits.
Repeat Step 1.
2
•  Inspect the spark plugs for damage, wear, and proper plug gap.
•  Is there any malfunction?
Yes
Replace the spark plugs, then go to Step 1.
No
Go to the next step.
3
•  Reconnect the spark plugs to the ignition coil.
•  Ground the spark plugs to the engine.
•  Is a strong blue spark visible at each cylinder while cranking the engine?
Yes
Ignition system is normal.
No
Some cylinders do not spark:
•  Go to the next step.
All cylinders do not spark:
•  Go to Step 5.
4
•  Inspect the open or short circuit in wiring harness between the following terminals (wiring harness-side):
―  Ignition coil No.1 terminal C—PCM terminal 2G
―  Ignition coil No.2 terminal C—PCM terminal 2K
―  Ignition coil No.3 terminal C—PCM terminal 2L
―  Ignition coil No.4 terminal C—PCM terminal 2H
•  Are the wiring harnesses normal?
Yes
Inspect and replace the ignition coil.
No
Repair or replace the malfunctioning part according to the inspection results, then go to Step 1.
5
•  Measure the voltage at terminal A (wiring harness-side) in each ignition coils.
•  Is the voltage B+?
Yes
Go to the next step.
No
Inspect the power supply circuit of ignition coils.
Repair or replace the malfunctioning part according to the inspection results.
6
•  Does the PCM connector or ignition coil connectors have a poor connection?
Yes
Repair or replace the connector, then go to Step 1.
No
Go to the next step.
7
•  Are the CKP sensor and crankshaft pulley normal?
Yes
Inspect for an open or short circuit in the wiring harness and connector of CKP sensor.
Repair or replace the malfunctioning part according to the inspection results.
No
Repair or replace the malfunctioning part according to the inspection results, then go to Step 1.


EGR Control System Inspection

1.  Crank the engine and verify that EGR valve operation (initial operation) sound is heard.

•  If the operation sound is not heard, connect the M-MDS to the DLC-2 and verify that the DTC P0403:00 is shown. Perform DTC inspection. (See DTC P0403:00 [LF, L5].)

2.  Start the engine and idle it.

3.  Warm up the engine to normal operating temperature.

4.  Access the following PIDs:

•  ECT, RPM, SEGRP DSD, APP1, APP2, VSS

5.  Idle the vehicle and verify that the SEGRP value is 0.

6.  Put the vehicle in drive.

7.  Depress the accelerator pedal and verify that the SEGRP DSD value is increased.

•  If the EGR valve increases, inspect the following:
―  EGR valve (stuck open or close)
―  Wiring harness and connectors (Main relay—EGR valve—PCM)
•  If the SEGRP DSD value does not increase, inspect the VSS, APP1, APP2, TP REL and ECT PIDs. (See PCM INSPECTION [LF, L5].)

8.  Stop the vehicle and verify that the SEGRP value returns to 0.


Purge Control System Inspection

1.  Start the engine.

2.  Disconnect the vacuum hose between the purge solenoid valve and the charcoal canister.

3.  Put a finger to the purge solenoid valve and verify that there is no vacuum applied when the engine is cold.

•  If there is a vacuum, inspect the following:
―  Wiring harness and connectors (Purge solenoid valve—PCM terminal 1BA)
―  Purge solenoid valve (See PURGE SOLENOID VALVE INSPECTION [LF, L5].)

4.  Warm up the engine to the normal operating temperature.

5.  Stop the engine.

6.  Connect the M-MDS to the DLC-2 and verify that the DTC P0443:00 is shown. Perform DTC inspection. (See DTC P0443:00 [LF, L5].)

7.  Switch the ignition to ON.

8.  Access ECT PID.

9.  Verify that the engine coolant temperature is more than 78 °C {172 °F}.

•  If the M-MDS indicates less than 78 °C {172 °F}, perform the ECT sensor inspection.

10.  Set the vehicle on the dynamometer or chassis roller.

Warning
•  When the dynamometer or chassis roller is operating, there is a possibility that the operator may come into contact with or be caught up in the rotating parts, leading to serious injuries or death. When performing work while the dynamometer or chassis roller is operating, be careful not to come into contact with or be caught up in any of the rotating parts.

11.  Drive vehicle at engine speed approx. 2,000 rpm for 30 s or more.

12.  Put a finger to the purge solenoid valve and verify that there is no vacuum applied while Step 2.

•  If there is no vacuum, inspect the following:
―  Wiring harness and connector (Main relay—Purge solenoid valve—PCM terminal 1BA)
―  Purge solenoid valve (See PURGE SOLENOID VALVE INSPECTION [LF, L5].)
―  MAF, APP1, APP2, TP REL and LOAD PIDs
•  If there is vacuum, inspect the following:
―  Vacuum hose (Purge solenoid valve—Charcoal canister)


A/C Cut-off Control System Inspection

1.  Start the engine.

2.  Turn the A/C switch and the fan switch on.

3.  Verify that the A/C compressor magnetic clutch actuates.

•  If it does not actuate, go to symptom troubleshooting “NO.23 A/C DOES NOT WORK SUFFICIENTLY”. (See NO.23 A/C DOES NOT WORK SUFFICIENTLY [LF, L5].)

4.  Fully open the throttle valve and verify that the A/C compressor magnetic clutch does not actuate for 2—5 s.

•  If it actuates, inspect as follows:
―  A/C relay (See RELAY INSPECTION.)
―  Open or short to ground circuit in wiring harness and connectors (Ignition switch—A/C relay—PCM terminal 1I)
―  A/C related parts
―  APP1, APP2 PIDs


Cooling Fan Control System Inspection

1.  Verify that the battery voltage is above 12.4 V.

•  If the battery voltage is below 12.4 V, charge the battery or connect the external power supply.

2.  Connect the M-MDS to the DLC-2.

3.  Access the following PIDs:

•  ECT
•  AC_REQ

4.  Turn the A/C switch to off.

5.  Verify that the ECT PID is below 98 °C {209 °F} and the AC_REQ is off.

•  If the ECT PID is below 98 °C {209 °F}, inspect the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [LF, L5].)
•  If the AC_REQ PID is on, perform the A/C symptom troubleshooting “NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY“. (See NO.24 A/C IS ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [LF, L5].)

6.  Switch the ignition to ON while the temperature is below 98 °C {209 °F} with the ignition is ON.

7.  Verify that the cooling fan is not operating.

•  If the cooling fan is operating inspect the following:
(1)  Verify that the FAN DUTY PID is 0%. (See ON-BOARD DIAGNOSTIC TEST [LF, L5].)
•  If the FAN DUTY PID is not 0%, inspect the following PID and related parts.
―  ECT (ECT sensor)
―  AC_REQ (Climate control unit, refrigerant pressure sensor, evaporator temperature sensor and instrument cluster)
―  VSS (Vehicle speed sensor)
―  ACCS (A/C magnetic clutch)
•  If the FAN DUTY PID is 0%, replace cooling fan component.

8.  Turn the A/C switch to on.

9.  Verify that the cooling fan is operating while the ECT PID is below 98 °C {209 °F}.

•  If the cooling fan does not operate, inspect for the following:
―  Climate control unit (A/C switch and fan switch)
―  A/C refrigerant pressure sensor
―  Communication error between instrument cluster and PCM
―  Communication error between climate control unit and instrument cluster
―  Fan control module power supply circuit (open or short circuit)
―  Fan control module GND circuit (open or short circuit)
―  Fan control module control signal circuit (open or short circuit between fan control module terminal 1C and PCM terminal 1R)
―  Fan control module (See COOLING FAN COMPONENT INSPECTION [LF, L5].)

10.  Turn the A/C switch to the off position.

11.  Start the engine and idle it.

12.  Verify that the cooling fan operating speed increases relative to the ECT PID increase.

•  If the cooling fan speed does not increase inspect the following:
―  ECT sensor (characteristic) (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [LF, L5].)
―  Fan control signal circuit (between fan control module terminal 1C and PCM terminal 1R)
•  If the all items are normal, replace the cooling fan component.


Variable Valve Timing Control System Operation Inspection


When idling cannot be continued

1.  Remove the OCV and verify that the spool valve is at maximum retard position.

2.  Connect the OCV.

3.  Switch the ignition to ON.

4.  Verify that the spool valve is at maximum retard position.

•  If the spool valve is stuck in the advance direction, inspect for the following:
―  Short circuit in wiring harnesses or connectors between the OCV and the PCM.

5.  Inspect the variable valve timing actuator. (See VARIABLE VALVE TIMING ACTUATOR INSPECTION [LF, L5].)


When idling can be continued

1.  Disconnect OCV connector.

2.  Warm up the engine and idle it.

3.  Apply battery voltage to the OCV and verify that the engine idles roughly or stalls.

•  If the engine idles roughly or stalls, inspect the timing chain component (valve timing deviation).
•  If the engine does not idle roughly or stalls, go to the next step.

4.  Remove the OCV and perform spool valve operation inspection. (See OIL CONTROL VALVE (OCV) REMOVAL/INSTALLATION [LF, L5].)

•  If not as specified, inspect the following:
―  Harnesses and connectors between OCV and PCM open or short.
•  If as specified, inspect the following hydraulic passages for clogging or leakage or both:
―  Oil pressure switch—OCV
―  OCV—Camshaft
―  Camshaft internal passage

5.  If they are normal, replace the camshaft pulley (with built-in variable valve timing actuator).