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 (A/F sensor, HO2S 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 NOTE: If fuel monitor DTC, DTC P0132:00 is retrieved, ignore it until P0140:00 is fixed. Switch the ignition to off, then to the 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	IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA Is the DTC P0140:00 on FREEZE FRAME DATA?	Yes	Go to the next step
4		No	Go to troubleshooting procedures for DTC on FREEZE FRAME DATA. (See DTC TABLE [L5] .)
5	INSPECT HO2S CONNECTOR CONDITION Switch the ignition to off. Disconnect the HO2S 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 13.
5		No	Go to the next step
6	INSPECT PCM CONNECTOR CONDITION Disconnect the PCM 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 13.
6		No	Go to the next step
7	INSPECT GAS LEAKAGE FROM EXHAUST SYSTEM Visually inspect the exhaust system from exhaust manifold to HO2S Is there any leakage?	Yes	Repair or replace the malfunctioning part according to the inspection results, then go to Step 13.
7		No	Go to the next step.
8	INSPECT HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND Inspect for continuity between HO2S terminal A (wiring harness-side) and body ground. Is there continuity?	Yes	Repair or replace the wiring harness for a possible short to ground, then go to Step 13.
8		No	Go to the next step
9	INSPECT HO2S SIGNAL CIRCUIT FOR OPEN CIRCUIT Inspect for continuity between HO2S terminal A (wiring harness-side) and PCM terminal 2Q (wiring harness-side) Is there continuity?	Yes	Go to the next step.
9		No	Repair or replace the wiring harness for a possible open circuit, then go to Step 13
10	INSPECT HO2S Inspect the HO2S. (See HEATED OXYGEN SENSOR (HO2S) INSPECTION [L5] .) Is there any malfunction?	Yes	Replace the HO2S, then go to Step 13. (See HEATED OXYGEN SENSOR (HO2S) REMOVAL/INSTALLATION [L5] .)
10		No	Go to the next step
11	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 the inspection results, then go to Step 13.
11		No	Go to the next step.
12	INSPECT ENGINE COMPRESSION Inspect engine compression. (See COMPRESSION INSPECTION [L5] .) Is there any malfunction?	Yes	Perform the engine overhaul for repairs, then go to the next step.
12		No	Go to the next step.
13	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] .)
13		No	Go to the next step.
14	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] .)
14		No	DTC troubleshooting completed.