Symptom Troubleshooting - Engine: Overview Mazda 3 BK

Scheme 422

1. When the customer reports a vehicle malfunction, check the Malfunction Indicator Lamp (MIL) indication and Diagnostic Trouble Code (DTC), then diagnose the malfunction according to the following flowchart: If a DTC exists, diagnose the applicable DTC inspection. (See DTC TABLE .) If no DTC exists and the MIL does not illuminate or flash, diagnose the applicable symptom troubleshooting. (See «QUICK DIAGNOSTIC CHART»(ref-177559-S34743863062005060200000) .)

MAIN RELAY OPERATION INSPECTION

1. Verify that the main relay clicks when the ignition switch is turned to ON position 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 terminal A. Harness and connector between PCM terminal 1AT and main relay terminal B.

VARIABLE INTAKE-AIR CONTROL OPERATION INSPECTION

1. Start the engine.
2. Inspect the rod operation under the following conditions

Scheme 423

Scheme 424

1. If the rod operation is not as specified, inspect as follows: Stop the engine. Connect the WDS or equivalent to the DLC-2. Verify that DTC P0661 or P0662 is not displayed. If DTC P0661 or P0662 is shown, perform DTC inspection. (See DTC TABLE .) Inspect the variable intake-air solenoid valve. (See VARIABLE INTAKE-AIR SOLENOID VALVE INSPECTION [LF] .) (See VARIABLE INTAKE-AIR SOLENOID VALVE INSPECTION [L3] .) If the variable intake-air solenoid valve is not normal, replace the variable intake-air solenoid valve. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF] .) (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3] .) If the variable intake-air solenoid valve is normal, inspect the following: Vacuum hose and vacuum chamber for looseness or damage. Shutter valve actuator. (See VARIABLE INTAKE-AIR SHUTTER VALVE ACTUATOR INSPECTION [LF] .) (See VARIABLE INTAKE-AIR SHUTTER VALVE ACTUATOR INSPECTION [L3] .) Shutter valve stuck open or closed.

VARIABLE TUMBLE CONTROL OPERATION INSPECTION

1. Connect the WDS or equivalent to the DLC-2.
2. Access ECT PID.
3. Verify that ECT PID is below 61.9 °C {143.4 °F} (LF), below 63 °C {145 °F} (L3) .
4. Start the engine.
5. Inspect rod operation under the following conditions

Scheme 425

1. If the rod operation is not specified, inspect as follows: Verify that DTC No. P2004, P2006, P2009 or P2010 is not displayed. If DTC No. P2004, P2006, P2009 or P2010 are shown, perform DTC inspection. (See DTC TABLE .) Inspect the variable tumble solenoid valve. (See VARIABLE TUMBLE SOLENOID VALVE INSPECTION [LF] .) (See VARIABLE TUMBLE SOLENOID VALVE INSPECTION [L3] .) If the variable tumble solenoid valve is not normal, replace the variable tumble solenoid valve. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [LF] .) (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L3] .) If the variable tumble solenoid valve is normal, inspect the following: Vacuum hose and vacuum chamber for looseness or damage. Shutter valve actuator. (See VARIABLE TUMBLE SHUTTER VALVE ACTUATOR INSPECTION [LF] .) (See VARIABLE TUMBLE SHUTTER VALVE ACTUATOR INSPECTION [L3] .) Shutter valve stuck open or closed.

Scheme 426

FUEL PUMP OPERATION INSPECTION

1. Remove the fuel-filler cap.
2. Turn the ignition switch to the ON position.
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 connector terminal C (California emission regulation applicable model), A (except for California emission regulation applicable model). Specification B+ (Ignition Switch 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 1AR (with immobilizer system), 1AQ (without immobilizer system). If not as specified, inspect the following: Fuel pump relay. Wiring harness connector (Main relay - fuel pump relay - fuel pump.)

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 maximum retard position.
2. Connect the Oil Control Valve (OCV).
3. Turn the ignition switch to the ON position.
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 Oil Control Valve (OCV) and the PCM.
5. Inspect the variable valve timing actuator. (See VARIABLE VALVE TIMING ACTUATOR INSPECTION [L3] .)