#
ENGINE CONTROL SYSTEM OPERATION INSPECTION [WITH WU-TWC]

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## Main Relay Operation Inspection

1. Verify that the main relay clicks when the ignition switch is turned to the ON position and than off.

  • If there is no operation sound, inspect the following.

  - Main relay
  - Immobilizer system (PATS) operation (if equipped)
  - Wiring harness and connector between the ignition switch and main relay terminal A.
  - Wiring harness and connector between PCM terminal 1AW and main relay terminal E.

## Intake Manifold Vacuum Inspection

1. Verify that the air intake hoses are installed properly.

2. Start the engine and idle it.

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

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

  • If it is not as specified, inspect the following.

Specification

  More than 60 kPa {450 mmHg, 18 inHg}

  Note

  • Air suction can be located by spraying lubricant to the area where the suction is occurring and revving the engine.

  - Air suction at the throttle body, intake manifold and PCV valve installation points
  - Accelerator cable free play
  - Fuel injector insulator
  - Engine compression

## Idle Air Control System Inspection

### Engine coolant temperature compensation inspection

1. Connect the WDS or equivalent to the DLC-2.

2. Select 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
  - IAC valve and related wiring harness

### Load compensation inspection

1. Start the engine and run at idle.

2. Connect the WDS or equivalent to the DLC-2.

3. Verify that P0511 not displayed.

  • If P0511 is displayed, carry out the DTC inspection.
  (See DTC table (With WU-TWC).)

4. Change the duty value of the IAC valve to 100 % using the IAC PID.

5. Verify that the idle speed increases.

  • If the idle speed does not change, inspect the following.

  - IAC valve air passage
  - Open or short circuit between the IAC valve connector terminals and PCM connector terminals 2X and 2AB

6. Select the following PIDs.

  • ACSW
  • IAC
  • PSP
  • RPM

  Note

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

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

  • If it is not at the specified load condition, inspect the following.

  - Refrigerant pressure switch (low, high) and related wiring harness
  - Fan switch and related wiring harness
  - PSP switch and related wiring harness

Engine speed

Condition | Idle speed (rpm)
--- | ---
P, N position (ATX) | Neutral (MTX)
No load | After the sensor detects the steering angle*1 | Steering angle is less than 60 ° | 650-750 | 600-700
Steering angle is above 60 ° | 650-750
Before the sensor detects the steering angle*1
A/C on | Low load*2 | 650-750
High load*3 | 700-800
Electrical load is on.*4 | 30-40 A | 650-750
above 40 A | 700-800
P/S on | After the sensor detects the steering angle*1 | Steering angle is less than 180 ° | 650-750
Steering angle is above 180 ° | 700-800
Before the sensor detects the steering angle*1

  *1 :
The steering angle will be cleared if the ignition switch is turned off. The sensor detects the steering angle after the ignition switch is turned to the ON position and the vehicle is driven straight at a vehicle speed of 20 km/h {12 mph} or more.
  *2 :
Refrigerant pressure switch (middle pressure) is off.
  *3 :
Refrigerant pressure switch (middle pressure) is on.
  *4 :
Generator generating current value

## Variable Intake-air System (VIS) Operation Inspection

1. Connect the WDS or equivalent to the DLC-2.

2. Carry out the KOEO self-test.

3. Verify that DTC P0660 is not displayed.

  • If DTC P0660 is displayed, carry out the DTC inspection.

4. Turn the ignition switch to the ON position (Engine off).

5. Turn the VIS shutter valve actuator from ON to OFF and from OFF to ON using the IMTV PID and verify that the operation sound of the actuator is heard.

  • If the operation sound is not heard, inspect the following.

  - VIS shutter valve actuator
  - VIS shutter valve actuator stuck open or close

## Variable Tumble Control System (VTCS) Operation Inspection

1. Connect the WDS or equivalent to the DLC-2.

2. Carry out the KOEO self-test.

3. Verify that DTC P2008 is not displayed.

  • If DTC P2008 is displayed, carry out the DTC inspection.

4. Turn the ignition switch to the ON position (Engine off).

5. Monitor the ECT, RPM and IMRC PIDs.

6. Verify that ECT PID is 60 °C {140 °F} or less.

7. Start the engine.

8. Verify that the IMRC PID is as shown below when the ECT PID is 60 °C {140 °F} or less.

  • If the IMRC PID is not as specified, inspect as follows.

  - TP sensor (misadjustment)

Engine speed

Engine speed | 3,250 rpm
--- | ---
Or less | Or more
IMRC PID | OFF | ON

9. Turn the VTCS shutter valve actuator from ON to OFF and from OFF to ON using the IMRC PID and verify that the operation sound of the actuator is heard.

  • If the operation sound is not heard, inspect the following.

  - VTCS shutter valve actuator
  - VTCS shutter valve actuator is stuck open or closed

## Fuel Injector Operation Inspection

STEP | INSPECTION | RESULTS | ACTION
--- | --- | --- | ---
1 | While cranking the engine, inspect the 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 | Carry out the main relay operation inspection. Is the main relay operation normal? | Yes | Inspect the following: • Fuel injector power system related wiring harness and connectors • PCM connectors • Fuel injector ground and related wiring harness and connectors
No | Repair or replace the malfunctioning parts.
3 | Change the fuel injector connector of the fuel injector that is not operating with an operating fuel injector. Is operation sound heard? | Yes | Go to the next step.
No | Replace the fuel injector.
4 | Are the wiring harness and connectors of the non-operational fuel injector normal? (Open or short circuit) | Yes | Inspect the PCM terminal voltage of the fuel injector signal.
No | Repair or replace the malfunctioning parts.

## Fuel Cut Control System Inspection

1. Warm up the engine and idle it.

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

3. Connect the WDS or equivalent to the DLC-2.

4. Select the RPM and FUELPW PIDs.

5. Monitor both PIDs while performing the following steps.

  (1) Depress the accelerator pedal and increase the engine speed to 4,000 rpm.
  (2) Release the accelerator pedal (brake pedal is not depressed) and verify that the fuel injector duration time is 0 ms, and 2-5 ms when the engine speed drops to 1,200 rpm or less.

  • If ti is not as specified, inspect the following:

  - ECT sensor and related wiring harness
  - Neutral/clutch pedal position switch and the related wiring harness (MTX)
  - TR switch and the related wiring harness (ATX)

## Fuel Pump Operation Inspection

1. Connect the WDS or equivalent to the DLC-2.

2. Remove the fuel-filler cap.

3. Turn the ignition switch to the ON position.

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

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

5. Measure the voltage at wiring harness-side fuel pump connector terminal B.

Specification

  B+ (Ignition switch is on)

  • If the voltage is as specified, inspect the following.

  - Fuel pump continuity
  - Fuel pump ground
  - Wiring harness between the fuel pump relay and PCM terminal 1AH

  • If it is not as specified, inspect the following.

  - Fuel pump relay
  - Wiring harness and connector (Main relay-fuel pump relay-fuel pump)

## Fuel Pump Control System Inspection

1. Connect the WDS or equivalent to the DLC-2.

2. Turn the ignition switch to the ON position.

3. Select FP PID.

4. Turn the fuel pump relay from off to on and verify if the operation sound of the fuel pump relay is heard.

  • If no operation sound is heard, inspect the fuel pump relay.
  • If the fuel pump relay is normal, inspect the following.

  - Wiring harnesses and connectors (Main relay-fuel pump relay-PCM)

## 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 a 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 spark plugs. • Remove the spark plugs. • Reconnect the spark plugs to ignition coil. • Ground the spark plugs to engine. • Is a strong blue spark visible at each cylinder while cranking? | Yes | Ignition system is normal.
No | Some cylinders do not spark: • Go to the next step. All cylinders do not spark: • Go to Step 4.
2 | • Inspect the spark plugs for damage, wear, carbon deposits, and proper plug gap. • Are the spark plugs normal? | Yes | Go to the next step.
No | Replace the spark plugs, then go to Step.1.
3 | • Inspect the following wiring harnesses for an open or short circuit: - Ignition coil No.1 terminal C-PCM terminal 2Y - Ignition coil No.2 terminal C-PCM terminal 2U - Ignition coil No.3 terminal C-PCM terminal 2Q - Ignition coil No.4 terminal C-PCM terminal 2M • Are the wiring harnesses normal? | Yes | Inspect and replace the ignition coil.
No | Repair or replace the malfunctioning parts, then go to Step.1.
4 | • Measure the voltage at terminal A in each ignition coils. • Is the voltage reading B+? | Yes | Go to the next step.
No | Inspect the power supply circuit of the ignition coils.
5 | • 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.
6 | • Are the following parts normal? - CKP sensor and crankshaft pulley | Yes | Inspect for an open or short circuit in the wiring harness and connector of the CKP sensor.
No | Repair or replace the malfunctioning parts, then go to Step.1.

## Purge Control System Inspection

1. Connect the WDS or equivalent to the DLC-2.

2. Start the engine and idle it.

3. Select the ECT PID.

4. Verify that the engine coolant temperature is 60 °C {140 °F} or more.

  • If the WDS or equivalent indicates 60 °C {140 °F} or less, carry out the ECT sensor inspection.

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

6. Put a finger to the purge solenoid valve and verify that vacuum is applied when the engine is cold.

  • If there is no vacuum, inspect the following.

  - Wiring harness and connectors (Purge solenoid valve terminal B-PCM terminal 2AV)
  - Purge solenoid valve

7. Stop the engine.

8. Verify that the DTC P0443 is shown. Carry out DTC inspection.

9. Turn the ignition switch to the ON position.

10. Select the EVAPCP PID.

11. Increase the duty value of the purge solenoid valve to 50 % and inspect if the operation sound of the valve is heard.

  • If the operation sound is heard, inspect for a loose or damaged vacuum hose. (Intake manifold-purge solenoid valve-charcoal canister)
  • If the operation sound is not heard, carry out the purge solenoid valve inspection.

## 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".

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.
  (1) Connect the WDS or equivalent to the DLC-2.
  (2) Turn the A/C switch off.
  (3) Turn the ignition switch to the ON position.
  (4) Select the ACCS PID.
  (5) Turn the A/C relay from off to on and inspect if the operation sound of the relay is heard.

  • If the operation sound is heard, inspect the TP PID.
  • If the operation sound is not heard, inspect the following.

  - A/C relay
  - Open or short to ground circuit in the wiring harness and connectors (Ignition switch-A/C relay-PCM terminal 1AL)
  - A/C related parts

## Cooling Fan Control System Inspection

### Cooling fan system operation

Engine condition | Cooling fan relay No.1 | Cooling fan relay No.2
ECT 100°C {212°F} or less | OFF | OFF
ECT 100°C {212°F} or more (until 97°C {207°F} or less) | ON | OFF
ECT 108°C {228°F} or more (until 105°C {230°F}) | ON | ON
A/C and fan switches are on. | ON | ON
ECT sensor malfunction | ON | ON

1. Connect the WDS or equivalent to the DLC-2.

2. Verify that the ECT PID is 100°C {212°F} or less.

3. Verify that the A/C switch and fan switch are off.

4. Start the engine and idle it.

5. Verify that the cooling fan is not operating.

  • If the cooling fan is operating, inspect the following:
  (1) Verify that ACCS PID is OFF.

  • If the ACCS PID is ON, inspect for a short to ground circuit between refrigerant pressure switch and PCM terminal 1Q.

  (2) Verify that the FAN1 PID is OFF.

  • If the FAN1 PID is ON, inspect the following:

  - DTC for ECT sensor (P0117, P0118)

  • If the FAN1 PID is ON, inspect the following:

  - Cooling fan relay No.1
  - Short to ground circuit between cooling fan relay No.1 and PCM terminal 1AT
  - Short to power between cooling fan relay No.1 and cooling fan motor
  - Cooling fan relay No.2
  - Short to ground circuit between cooling fan relay No.2 and PCM terminal 1I
  - Short to power between cooling fan relay No.2 and cooling fan motor

6. Warm up the engine to the engine coolant temperature is 100 °C {212 °F} or more.

7. Verify that the cooling fan is operating.

  • If the cooling fan is not operating, inspect following procedure.
  (1) Cool the engine until the engine coolant temperature is 97 °C {207 °F} or less.
  (2) Select FAN1 PID.
  (3) Send an ON command and verify that the operation sound from cooling fan relay No.1 is heard.

  • If the operation sound is heard, inspect the following:

  - Open circuit between cooling fan relay No.1 and cooling fan motor
  - Open circuit between cooling fan motor and ground.
  - Cooling fan motor

  • If the operation sound is heard, inspect the following:

  - Cooling fan relay
  - Open circuit between ignition switch and PCM terminal 1AT through cooling fan relay

8. Turn the A/C switch and fan switch to ON with the engine idling.

9. Verify that the cooling fan speed is higher than Step 7.

  • If the cooling fan speed does not rise, inspect the following procedure.
  (1) Verify that the ACCS PID is ON.

  • If the ACCS PID is OFF, inspect following:

  - A/C switch
  - Fan switch
  - Refrigerant pressure switch (low & high pressure)
  - Evaporator temperature sensor (Evaporator temperature is too low.)
  - Open circuit between the refrigerant pressure switch and PCM terminal 1Q

  (2) Select the FAN2 PID.
  (3) Send an ON command and verify that the operation sound from cooling fan relay No.2 is heard.

  • If the operation sound is heard, inspect the following:

  - Open circuit between cooling fan relay No.2 and cooling fan motor
  - Open circuit between cooling fan motor and ground
  - Cooling fan

  • If the operation sound is not heard, inspect the following:

  - Cooling fan relay No.2
  - Open circuit between ignition switch and PCM terminal 2I through cooling fan relay No.2.

## Variable Valve Timing Control System Operation Inspection

### When idling cannot be continued

1. Remove the oil control valve (OCV) and verify that the spool valve is at the maximum retard position.

2. If the spool valve is stuck in the advance direction, replace the OCV.

3. Connect the OCV.

4. Turn the ignition switch to the ON position.

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

6. If the spool valve is stuck in the advance direction, inspect for the following.

  • Short circuit in harnesses or connectors between the OCV and the PCM.

7. Inspect the variable valve timing actuator.

### When idling can be continued

1. Warn up the engine.

2. Connect the WDS or equivalent to the DLC-2.

3. Idle the engine.

4. Select the VT DUTY1 PID.

5. Set the OCV duty valve to 100% and verify that the engine idles roughly or stalls.

  • If as specified, inspect the timing belt component (valve timing deviation).
  • If it is not as specified, go to the next step.

6. Remove the OCV and connect the OCV connector to the OCV.

7. Turn the ignition switch to the ON position.

8. Select the VT DUTY1 PID.

9. Set the OCV duty value to 100% and verify that the spool valve operates in the advance direction.

10. If it is not as specified, inspect the following.

  • OCV operation.
  • Harnesses and connectors between the OCV and the PCM for an open or short circuit.

11. Inspect the following hydraulic passages for clogging and/or leakage.

  • Oil pressure switch-OCV
  • OCV-camshaft
  • Camshaft internal passage

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

## 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 WDS or equivalent to the DLC-2 and verify that DTC P0403 is shown. Perform the DTC inspection.

2. Start the engine and idle it.

3. Increase the step value of EGR valve from 0 to 40 using the SEGRP PID.

4. Operate the EGR valve and inspect if the engine speed becomes unstable or the engine stalls.

  • If the engine speed does not change, perform the following.
  (1) Stop the engine.
  (2) Remove the EGR valve.
  (3) Connect the EGR valve connector.
  (4) Turn the ignition switch to the ON position.
  (5) Increase the step value of the EGR valve from 0 to 40 using the SEGRP PID.
  (6) Inspect the EGR operation.

  • If the EGR valve operates, clean the EGR valve and reinspect from Step 2.
  • If the EGR valve does not operate, replace the EGR valve and reinspect from Step 2.

5. Start the engine and warm it up completely.

6. Access the following PIDs.

  • ECT
  • RPM
  • SEGRP
  • TP
  • VSS

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

8. Drive the vehicle.

9. Depress the accelerator pedal and verify that the SEGRP value increases.

  • If the SEGRP value does not increase, inspect the VSS, TP and ECT PIDs.

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