Diagnostic procedure

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED Have FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS (misfire related) been recorded?	Yes	Go to the next step.
1		No	Record FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS on repair order, then go to the next step.
2	VERIFY RELATED REPAIR INFORMATION AVAILABILITY Verify related Service Bulletins and/or on-line repair information availability. Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	VERIFY RELATED PENDING AND STORED DTC Switch the ignition to off, then to ON (engine off). Verify pending and stored DTCs using the M-MDS. Are any other DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [L5] .)
3		No	Go to the next step.
4	VERIFY CURRENT INPUT SIGNAL STATUS Access the following PIDs using the M-MDS. (See PCM INSPECTION [L5] .) APP1 APP2 ECT IAT MAF RPM TPREL VSS Is there any signal that is far out of specification when switch the ignition to ON and the engine idles?	Yes	Repair or replace the malfunctioning part according to inspection results, then go to Step 25.
4		No	Go to the next step.
5	VERIFY CURRENT INPUT SIGNAL STATUS UNDER FREEZE FRAME DATA CONDITION Access the following PIDs under FREEZE FRAME DATA condition (See PCM INSPECTION [L5] .) APP1 APP2 ECT IAT MAF RPM TP REL VSS Is there any signal which causes drastic changes?	Yes	Repair or replace the malfunctioning part according to inspection results, then go to Step 25.
5		No	Go to the next step.
6	INSPECT CMP SENSOR CONNECTOR CONDITION Switch the ignition to off Disconnect the CMP sensor connector. Inspect for poor connection (such as damaged/pulled-out pins, corrosion). Is there any malfunction?	Yes	Repair or replace the terminal and/or connector, then go to Step 25
6		No	Go to the next step.
7	INSPECT CMP SENSOR Inspect the CMP sensor (See CAMSHAFT POSITION (CMP) SENSOR INSPECTION [L5] .) Is there any malfunction?	Yes	Replace the CMP sensor, then go to Step 25. (See CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION [L5] .)
7		No	Go to the next step
8	INSPECT CKP SENSOR CONNECTOR CONDITION Disconnect the CKP sensor connector. Inspect for poor connection (such as damaged/pulled-out pins, corrosion) Is there any malfunction?	Yes	Repair or replace the terminal and/or connector, then go to Step 25
8		No	Go to the next step.
9	INSPECT CKP SENSOR Inspect the CKP sensor (See CRANKSHAFT POSITION (CKP) SENSOR INSPECTION [L5] .) Is there any malfunction?	Yes	Replace the CKP sensor, then go to Step 25. (See CRANKSHAFT POSITION (CKP) SENSOR REMOVAL/INSTALLATION [L5] .)
9		No	Go to the next step.
10	INSPECT IGNITION SYSTEM OPERATION Perform the spark test. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L5] .) Is strong blue spark visible at each cylinder?	Yes	Go to Step 14.
10		No	Go to the next step.
11	INSPECT SPARK PLUG CONDITION Remove the spark plug. Inspect the spark plug. (See SPARK PLUG INSPECTION [L5] .) Is there any malfunction?	Yes	Replace the spark plug, then go to Step 25. (See SPARK PLUG REMOVAL/INSTALLATION [L5] .)
11		No	Go to the next step.
12	INSPECT IGNITION COIL RELATED WIRING HARNESS Inspect the ignition coil related wiring harness condition (intermittent open or short) for all cylinders Is there any malfunction?	Yes	Repair or replace the malfunctioning wiring harness, then go to Step 25.
12		No	Go to the next step.
13	INSPECT IGNITION COIL Inspect the ignition coil for all cylinders. (See IGNITION COIL INSPECTION [L5] .) Is there any malfunction?	Yes	Replace the malfunctioning ignition coil, then go to Step 25. (See IGNITION COIL REMOVAL/INSTALLATION [L5] .)
13		No	Go to the next step.
14	VERIFY PID DATA FOR MAF SENSOR MALFUNCTION Connect the M-MDS to the DLC-2 Access the MAF PID using the M-MDS. Race the engine and verify that the MAF PID changes quickly according to change in the engine speed Is the MAF PID response normal?	Yes	Go to the next step.
14		No	Replace the MAF sensor, then go to Step 25. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [L5] .)
15	INSPECT INTAKE AIR SYSTEM FOR AIR SUCTION Inspect for air leakage between the following: MAF sensor and throttle body Throttle body and intake manifold Is there any leakage?	Yes	Repair or replace the malfunctioning part according to inspection results, then go to Step 25.
15		No	Go to the next step.
16	INSPECT FUEL LINE PRESSURE Inspect the fuel line pressure. (See FUEL LINE PRESSURE INSPECTION [L5] .) Is there any malfunction?	Yes	Go to the next step.
16		No	Go to Step 19.
17	INSPECT FUEL LINE LEAKAGE Visually inspect the leakage from fuel line. Is there any leakage?	Yes	Repair or replace the malfunctioning part according to inspection results, then go to Step 25.
17		No	Go to the next step.
18	INSPECT FUEL FILTER Visually inspect the foreign materials or stain inside fuel filter Is there any foreign materials or stain?	Yes	Repair or replace the malfunctioning part according to inspection results, then go to Step 25.
18		No	Replace the fuel pump unit, then go to Step 25. (See FUEL PUMP UNIT REMOVAL/INSTALLATION [L5] .)
19	VERIFY SIMULATION ITEM FOR PURGE SOLENOID VALVE MALFUNCTION Switch the ignition to off. Connect the vacuum pump to the purge solenoid valve and apply vacuum to the solenoid. Verify that the solenoid holds vacuum. Switch the ignition to ON (engine off). Access the EVAPCP PID in SIMULATION TEST using the M-MDS. Set the purge solenoid value to 100 % for the EVAPCP PID Verify that the purge solenoid value releases vacuum while the 100 % for the EVPCP PID. Is the purge solenoid valve operation normal?	Yes	Go to the next step.
19		No	Replace the purge solenoid valve, then go to Step 25 (See PURGE SOLENOID VALVE REMOVAL/INSTALLATION [L5] .)
20	INSPECT VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION Perform the Variable Valve Timing Control System Operation Inspection. (See ENGINE CONTROL SYSTEM OPERATION INSPECTION [L5] .) Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to inspection results, then go to Step 25.
20		No	Go to the next step.
21	INSPECT EGR VALVE Inspect the EGR valve. (See EGR VALVE INSPECTION [L5] .) Is there any malfunction?	Yes	Replace the EGR valve, then go to Step 25. (See EGR VALVE REMOVAL/INSTALLATION [L5] .)
21		No	Go to the next step.
22	INSPECT PCV VALVE OPERATION Remove the PCV valve Inspect the PCV valve operation (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE INSPECTION [L5] .) Is there any malfunction?	Yes	Replace the PCV valve, then go to Step 25. (See POSITIVE CRANKCASE VENTILATION (PCV) VALVE REMOVAL/INSTALLATION [L5] .)
22		No	Go to the next step.
23	INSPECT SEALING OF ENGINE COOLANT PASSAGE Perform the "ENGINE COOLANT LEAKAGE INSPECTION". (See ENGINE COOLANT LEAKAGE INSPECTION [L5] .) Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to inspection results, then go to Step 25.
23		No	Go to the next step.
24	INSPECT ENGINE COMPRESSION Inspect the engine compression. (See COMPRESSION INSPECTION [L5] .) Is there any malfunction?	Yes	Perform the engine overhaul for repairs, then go to the next step.
24		No	Go to the next step.
25	VERIFY DTC TROUBLESHOOTING COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. Start the engine and warm it up completely. Is the PENDING CODE for this DTC present?	Yes	Replace the PCM, then go to the next step. (See PCM REMOVAL/INSTALLATION [L5] .)
25		No	Go to the next step.
26	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE [L5] .) Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [L5] .)
26		No	DTC troubleshooting completed.