Symptom Troubleshooting (Engine Control System) Aj: Diagnosis Mazda MPV II рестайлинг

Inspection Method for Sensors

1. Connect WDS or equivalent to DLC-2.
2. Turn ignition key to ON (Engine OFF). NOTE: If engine starts and runs, perform the following steps at idle.
3. Access PIDs for the switch you are inspecting.
4. Vibrate the sensor slightly with your finger. If PID value is unstable, or malfunction occurs, check for poor connection and/or poorly mounted sensor.

Scheme 234

1. Connect WDS or equivalent to DLC-2.
2. Turn ignition key to ON (Engine OFF). NOTE: If engine starts and runs, perform the following steps at idle.
3. Prepare the SIMULATION TEST for actuators or relays that you are inspecting.
4. Vibrating the actuator or relay with your finger for 3 seconds after SIMULATION TEST is activated. If a variable click sound is heard, check for poor connection and/or poorly mounted actuator or relay. NOTE: Vibrating relays too strongly may result in open relays.

Intake Manifold Vacuum Inspection

1. Verify 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 (See COMPRESSION INSPECTION .) Specification: More than 60 kPa {450 mmHg, 18 inHg}

Engine coolant temperature compensation Inspection

1. Connect the SSTs (WDS or equivalent) to 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 decrease slowly, inspect the following. ECT sensor and related harness (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION .) IAC valve and related harness (See IDLE AIR CONTROL (IAC) VALVE INSPECTION .)

Scheme 235

Scheme 236

1. Start the engine and run it at idle.
2. Warm up the engine to normal operating temperature.
3. Connect the SSTs (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 .) MAF sensor and related harness (See MASS AIRFLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR INSPECTION .)

Spark Test

1. Disconnect the fuel pump relay.
2. Verify that each high-tension lead and connector is connected properly.
3. Inspect the ignition system in the following procedure.

Scheme 237

Evaporative system test outline

1. To verify that the problem has been fixed properly after repairs, the run Drive Cycle or evaporative system test must be performed.
2. The evaporative system test, which can substituted for the run Drive Cycle as an EVAP control system repair confirmation method, can be done while operating the WDS at idle instead of actually driving the vehicle.

Scheme 238

Scheme 239

1. The evaporative system test finds gas leaks in the system using the PCM to monitor changes in the EVAP system leak detection pump air pump load current. This test starts after sending an on-demand test signal from the WDS to the PCM. The PCM controls the Air pump and Change over valve (COV) operation and also stores the load current of the air pump as follows. The PCM commands turn the air pump up and retrieve the air pump load current value (LDP_MON PID) as a reference current (LDP_REF PID). After retrieving a reference current value, the PCM commands the Change over valve (COV) to open, then captures the air pump load current value (LDP_MON PID) as idle current (LDP_IDL PID). The evaporative system will be pressurized from the phase. The PCM continues to monitor the air pump load current value (LDP_MON PID) until the end of the test.
2. You can confirm whether any evaporative gas leak occurred or not by reading the test results.