Intention of troubleshooting procedure

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

Step 1-2
- Perform an ignition system parts inspection.
Step 3
- Perform a fuel injector control system inspection.
Step 4-9
- Perform an inspection of parts which may be affected by misfire except for ignition-related parts and fuel injection control-related parts.
Repair completion verification
- Verify that primary malfunction is resolved and there are no other malfunctions.

TROUBLESHOOTING DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	PURPOSE: INSPECT SPARK PLUG FOR MALFUNCTION Inspect the applicable part. (See SPARK PLUG INSPECTION (VIN M) .) (See SPARK PLUG INSPECTION (VIN L) .) Is the part normal?	Yes	Go to the next step.
1		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See SPARK PLUG REMOVAL/INSTALLATION (VIN M) .) (See SPARK PLUG REMOVAL/INSTALLATION (VIN L) .)
2	PURPOSE: INSPECT IGNITION COIL FOR MALFUNCTION Inspect the applicable part. (See IGNITION COIL INSPECTION (VIN M) .) (See IGNITION COIL INSPECTION (VIN L) .) Is the part normal?	Yes	Go to the next step.
2		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION (VIN M) .) (See IGNITION COIL/ION SENSOR REMOVAL/INSTALLATION (VIN L) .)
3	PURPOSE: INSPECT FUEL INJECTOR FOR MALFUNCTION Inspect the applicable part. (See FUEL INJECTOR INSPECTION (VIN M) .) (See FUEL INJECTOR INSPECTION (VIN L) .) Is the part normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See FUEL INJECTOR REMOVAL/INSTALLATION (VIN M) .) (See FUEL INJECTOR REMOVAL/INSTALLATION (VIN L) .)
4	PURPOSE: VERIFY IF MALFUNCTION RELATED TO INTAKE-AIR SYSTEM IS CAUSE OF MISFIRE Visually inspect for loose, cracked or damaged hoses on intake air system. Is there any malfunction?	Yes	Repair or replace the malfunctioning location and perform the repair completion verification.
4		No	Go to the next step.
5	PURPOSE: VERIFY IF POOR DRIVE BELT ASSEMBLY IS CAUSE OF MISFIRE Verify the condition of the drive belt assembly. (See DRIVE BELT INSPECTION (VIN M) .) (See DRIVE BELT INSPECTION (VIN L) .) Is there any malfunction?	Yes	Assemble drive belt correctly and perform the repair completion verification. (See DRIVE BELT REMOVAL/INSTALLATION (VIN M) .) (See DRIVE BELT REMOVAL/INSTALLATION (VIN L) .)
5		No	Go to the next step.
6	PURPOSE: VERIFY IF FOREIGN MATTER ON DRIVE BELT IS CAUSE OF MISFIRE Verify if oil is on the drive belt. Is there foreign matter on the drive belt?	Yes	Remove the foreign matter on the drive belt and perform the repair completion verification.
6		No	Go to the next step.
7	PURPOSE: INSPECT DRIVE BELT AUTO TENSIONER FOR MALFUNCTION Inspect the applicable part. (See DRIVE BELT AUTO TENSIONER INSPECTION (VIN M) .) (See DRIVE BELT AUTO TENSIONER INSPECTION (VIN L) .) Is the part normal?	Yes	Go to the next step.
7		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See DRIVE BELT AUTO TENSIONER REMOVAL/INSTALLATION (VIN M) .) (See DRIVE BELT AUTO TENSIONER REMOVAL/INSTALLATION (VIN L) .)
8	PURPOSE: VERIFY IF MALFUNCTION RELATED TO ENGINE COMPRESSION IS CAUSE OF MISFIRE Inspect the engine compression. (See COMPRESSION INSPECTION (VIN M) .) (See COMPRESSION INSPECTION (VIN L) .) Are compression pressures within specification?	Yes	Go to the next step.
8		No	Replace or overhaul the engine and perform the repair completion verification.
9	PURPOSE: VERIFY IF MALFUNCTION RELATED TO SEALING OF ENGINE UNIT (COMBUSTION CHAMBER AND ENGINE COOLANT PASSAGE) IS CAUSE OF MISFIRE Perform the "ENGINE COOLANT LEAKAGE INSPECTION". (See ENGINE COOLANT LEAKAGE INSPECTION (VIN M) .) (See ENGINE COOLANT LEAKAGE INSPECTION (VIN L) .) Does the radiator cap tester needle drop even though there is no engine coolant leakage from the radiator or the hoses?	Yes	Engine coolant leakage from the engine (between the combustion chamber and the engine coolant passage) may have occurred. Verify the conditions of the gasket and the cylinder head. If there is any malfunction: Repair or replace the malfunctioning location and perform the repair completion verification.
9		No	Go to the next step.
Repair completion verification 1	PURPOSE: VERIFY THAT VEHICLE IS REPAIRED Install/connect the part removed/disconnected during the troubleshooting procedure. Clear the DTC recorded in the memory. (See CLEARING DTC .) Replicate the vehicle conditions at the time the DTC was detected using the following procedure. Implement the repeatability verification procedure. (See REPEATABILITY VERIFICATION PROCEDURE .) Perform the DTC inspection for the PCM. (See DTC INSPECTION .) Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW (US) .) If the CAN communication is normal, perform the diagnosis from Step 1. If the malfunction recurs, replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION (VIN M) .) (See PCM REMOVAL/INSTALLATION (VIN L) .)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	PURPOSE: VERIFY IF OTHER DTCs DISPLAYED Perform the DTC inspection. (See DTC INSPECTION .) Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.