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ENGINE CONTROL SYSTEM OPERATION INSPECTION [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513)

BME010300103236

## Input Signal System Investigation Procedure

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

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

3. Repair or replace the defective part.

4. Confirm that the unusual signal has been erased.

### Finding unusual signals

While referring to ON-BOARD DIAGNOSTIC TEST [AJ], 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 the specifications by a wide margin are unusual.

2. When recreating the problem, any sudden change in monitor input signals that is not consciously created by the driver can be judged as unusual.

### Locating the source of unusual signals

  Caution

  • Compare the WDS or equivalent 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 GND to the GND of the PCM that is being tested, or to the engine itself. If this is not done, 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 harness or terminal from water damage, leading to problems with the vehicle.

### Variable resistance type 1 (TP sensor and EGR boost sensor)

### Investigate the input signal system for variable resistance type 1

1. When you get an unusual signal, measure the #1 PCM terminal voltage.

  • If the #1 terminal voltage and the WDS or equivalent monitor voltage are the same, proceed to the next step.
  • If there is a difference of 0.5 V or above, 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 above difference between the sensor and the WDS or equivalent voltages, inspect the harness for open or short circuits.
  • If the sensor and the WDS or equivalent voltages are the same, inspect for the following points concerning the sensor connector.
  • If there are no problems, proceed to next investigation below.

  - Female terminal opening is loose.
  - Coupler (pin holder) damage
  - Pin discoloration (blackness)

### Investigate the standard power supply system 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 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
  • Wiring harness/pin crimp is loose or disconnected.

### Investigate the GND system 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 open or short circuit in wiring harness
  • Coupler (pin holder) damage
  • Pin discoloration (blackness)
  • Wiring harness/pin crimp is loose or disconnected.

### Variable resistance type 2 (fuel tank level sensor and mass air flow (MAF) sensor)

### Investigate the GND system 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)
  • Wiring harness/pin crimp is loose or disconnected.

### Investigate the input signal system for variable resistance type 2

1. When you get an unusual signal, measure the #1 PCM terminal voltage.

  • If the #1 terminal voltage and the WDS or equivalent monitor voltage are the same, proceed to the next step.
  • If there is a difference of 0.5 V or above, inspect for the following points concerning the PCM connector.

  - Female terminal opening is loose.
  - Coupler (pin holder) damage
  - Pin discoloration (blackness)
  - Wiring harness/pin crimp is loose or disconnected.

2. Measure the #2 sensor terminal voltage.

  • If there is a 0.5 V or above difference between the sensor and the WDS or equivalent voltages, inspect the wiring harness for open or short circuits.
  • If the sensor and the WDS or equivalent voltages are the same, inspect the following points concerning the sensor connector.

  - Female terminal opening is loose.
  - Coupler (pin holder) damage
  - Pin discoloration (blackness)
  - Wiring harness/pin crimp is loose or disconnected.

  • If there are no problems, proceed to next investigation below.

### Investigate the electrical supply system 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
  • Wiring harness/pin crimp is loose or disconnected.

### Thermistor type (IAT sensor and ECT sensor)

### Investigate the input signal system for thermistor type

1. When you get an unusual signal, measure the #1 PCM terminal voltage.

  • If the #1 terminal voltage and the WDS or equivalent monitor voltage are the same, proceed to the next step.
  • If there is a difference of 0.5 V or above, inspect the following points concerning the PCM connector.

  - Female terminal opening loose
  - Coupler (pin holder) damage
  - Pin discoloration (blackness)
  - Wiring harness/pin crimp is loose or disconnected.

2. Measure the #2 sensor terminal voltage.

  • If there is a 0.5 V or above difference between the sensor and the WDS or equivalent voltages, inspect the harness for open or short circuits.
  • If the sensor and the WDS or equivalent voltages are the same, inspect the following points concerning the sensor connector.

  - Female terminal opening is loose.
  - Coupler (pin holder) damage
  - Pin discoloration (blackness)
  - Wiring harness/pin crimp is loose or disconnected.

  • If there are no problems, proceed to next investigation below.

### Investigate the GND system 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)
  • Wiring harness/pin crimp is loose or disconnected.

### VSS

1. Measure the #1 PCM terminal voltage and confirm that it is at 0 V or 5 V when the ignition switch is at the ON position and the engine at idle.

  • If it is at 0 V or 5 V, intermittent concern exists. (See INTERMITTENT CONCERN TROUBLESHOOTING [AJ].)
  • If not, inspect the following points concerning the PCM connector.
  • If there is no problem, inspect for the following.

  - Female terminal opening is loose.
  - Coupler (pin holder) damage
  - Pin discoloration (blackness)
  - Wiring harness/pin crimp is loose or disconnected.

2. Measure the #2 sensor terminal voltage and confirm that it is at 0 V or 5 V when the ignition switch is at the ON position and the engine at idle.

  • If it is at 0 V or 5 V, intermittent concern exists. (See INTERMITTENT CONCERN TROUBLESHOOTING [AJ].)
  • If not, inspect the following points concerning the sensor connector.
  • If there is no problem, inspect for the following.

  - Female terminal opening is loose.
  - Coupler (pin holder) damage
  - Pin discoloration (blackness)
  - Wiring harness/pin crimp is loose or disconnected.

3. Confirm that the #3 terminal switch voltage is at 0 V.

  • If it is at 0 V, inspect the sensor. If necessary, replace 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)
  - Wiring harness/pin crimp is loose or disconnected.

## Intake Manifold Vacuum Inspection

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

2. Start the engine and run it at idle.

3. Measure the manifold vacuum using a vacuum gauge.

  • If not as specified, inspect following.

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

Specification

  Above 60 kPa {450 mmHg, 18 inHg}

## Idle Air Control Inspection

### Engine coolant temperature compensation inspection

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

2. Select the PID/DATA MONITOR AND RECORD function on the WDS or equivalent display.

3. Select the following PIDs.

  • ECT
  • RPM

4. Verify that the engine is in cold condition, then start the engine.

5. 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 [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513).)
  - IAC valve and related wiring harness (See IDLE AIR CONTROL (IAC) VALVE INSPECTION [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513).)

## Fuel Injector Operation Inspection

STEP | INSPECTION | ACTION
--- | --- | ---
1 | • While cranking the engine, inspect for the fuel injector operation sound at each cylinder using a soundscope. • Is operation sound heard? | Yes | The fuel injector operation is normal.
No | All cylinders no heard: • Go to the next step. Some cylinders no heard: • Go to step 3.
2 | • Carry out main relay operation inspection. • Is main relay operation normal? | Yes | Inspect the following. • Fuel injector power system related wiring harness and connectors • PCM connectors • Fuel injector GND and related wiring harness and connectors
No | Repair or replace the malfunctioning part.
3 | • Change the fuel injector connector of the not operating fuel injector and the 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 not operating fuel injector normal? (Open or short circuit) | Yes | Inspect the PCM terminal voltage of the fuel injector signal.
No | Repair or replace the malfunctioning part.

## Ignition Control Inspection

1. Start the engine and run it at idle.

2. Warm up the engine to normal operating temperature.

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

4. Select the PID/DATA MONITOR AND RECORD function on the WDS or equivalent display.

5. Select the SPARKADV PID.

6. Verify that SPARKADV PID is within the specification.

Specification

  BTDC 4°-16° (10° ± 6°)

7. Increase the engine speed and verify that the SPARKADV PID value is advanced.

  • If it is not advanced, inspect the following.

  - CKP sensor and related harness (See CRANKSHAFT POSITION (CKP) SENSOR INSPECTION [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513).)
  - MAF sensor and related harness (See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION [AJ] (VIN: JMZ LW19J7*# 300001-, JM0 LW10J300 300001-301405, JM6 LW10J300 300001-, JM8 LW28J**# 300001-301513).)

## 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. • Reconnect the spark plugs to the ignition coil. • Ground the spark plugs to the engine. • Is strong blue spark visible at each cylinder while cranking? | Yes | The 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 open or short circuit:

  - Ignition coil No.1 terminal B-PCM terminal 26
  - Ignition coil No.2 terminal B-PCM terminal 52
  - Ignition coil No.3 terminal B-PCM terminal 78
  - Ignition coil No.4 terminal B-PCM terminal 1
  - Ignition coil No.5 terminal B-PCM terminal 27
  - Ignition coil No.6 terminal B-PCM terminal 82

• Are the wiring harnesses normal?
Yes
Inspect and replace ignition coil.
(See IGNITION COIL INSPECTION [AJ].)
No | Repair or replace the malfunctioning part, then go to Step.1.
4 | • Measure the voltage at terminal A in each ignition coils. • Is the voltage B+? | Yes | Go to the next step.
No | Inspect the power supply of the ignition coils.
5 | • Does the PCM connector or the ignition coil connectors have 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
  - PCM terminal 21/22 voltage

Specification

Approx. 1.5 V

Yes
Inspect for open or short circuit in the wiring harness and the connector of the CKP sensor.
No | Repair or replace the malfunctioning part, then go to Step.1.

## Main Fan/Additional Fan Motor Operation Inspection

1. Cool down the engine.

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

3. Turn the ignition switch to the ON position.

4. Turn A/C switch off.

5. Verify that the main fan/additional fan are not operated.

  • If the main fan/additional fan are operated, verify FAN_DUTY PID.

  - If FAN_DUTY PID value is not 0%, inspect the following PIDs.

  • ECT (voltage)
  • AC_REQ

  - If FAN_DUTY PID value is 0%, inspect the following:

  • Fan control module
  • Open or short to ground circuit between fan control module and PCM

6. Increase FAN_DUTY PID value from 0% to 100% gradually by Datalogger/simulation function. Verify that both main fan and additional fan operation speed increase in accordance with FAN_DUTY PID value changes.

  Note

  • The main fan and the additional fan are not rotate when FAN_DUTY PID value is lower than 30% by fan motor internal friction.

  • If there is a problem, perform the following steps:
  (1) Verify clicking sound of fan relay when the ignition switch is turned to the ON position.

  • If there is no clicking sound, inspect the following:

  - Fan relay
  - Open circuit between main relay and fan relay

  • If clicking sound heard, go to the next step.

  (2) Inspect the following parts in order in accordance with the fan operation condition.

  • Both main fan and additional fan do not operate.

  - Open circuit between fan control module and fan relay
  - Open circuit in fan control module ground harness
  - Poor connection of fan control module connector
  - Fan control module

  • Only main fan does not operate.

  - Open or short to ground circuit between fan control module and main fan motor
  - Poor connection of fan control module connector and/or main fan motor connector
  - Main fan motor malfunction
  - Fan control module

  • Only additional fan does not operate.

  - Open or short to ground circuit between fan control module and additional fan motor
  - Poor connection of fan control module connector and/or additional fan motor connector
  - Additional fan motor malfunction
  - Fan control module