Diagnostic Procedure

WARNING: This page is about a different car, the 2017 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	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.
1		No	Go to the next step.
2	VERIFY RELATED PENDING CODE AND/OR DTC Switch the ignition off, then ON (engine off). Perform the Pending Trouble Code Access Procedure and DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .) Are any other PENDING CODEs and/or DTCs present?	Yes	Go to the applicable PENDING CODE or DTC inspection. (See DTC TABLE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .)
2		No	Go to the next step.
3	INSPECT VEHICLE CONDITION FOR EFFECT ON MALFUNCTION Verify how the customer drives the vehicle by asking the customer the following: Engine speed is high and remains high for continuous long periods like when climbing a long steep grade. Is the engine generating excessive heat when driven?	Yes	Go to the next step.
3		No	Go to Step 5.
4	DETERMINE IF MALFUNCTION CAUSE IS OVERHEATING OR OTHER Access the ECT PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .) CAUTION: While performing this step, always operate the vehicle in a safe and lawful manner. When the M-MDS is used to observe monitor system status while driving, be sure to have another technician with you, or record the data in the M-MDS using the PID/DATA MONITOR AND RECORD capturing function and inspect later. Is the ECT PID value less than 122 °C {252 °F} while the vehicle is driven on a flat road?	Yes	Explain to the customer that the vehicle is normal. Go to Step 6.
4		No	The cause of this concern could be from the cooling system overheating. Perform the symptom troubleshooting "NO. 17 COOLING SYSTEM CONCERNS OVERHEATING". (See NO. 17 COOLING SYSTEM CONCERNS-OVERHEATING [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
5	INSPECT ECT SENSOR Inspect the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR INSPECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Is there any malfunction?	Yes	Replace the ECT sensor, then go to the next step. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
5		No	Go to the next step.
6	VERIFY DTC TROUBLESHOOTING COMPLETED Always reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. (See AFTER REPAIR PROCEDURE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .) Start the engine and warm it up completely. Drive the vehicle. Perform the DTC Reading Procedure. (See ON-BOARD DIAGNOSTIC TEST [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .) Is the same DTC present?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the PCM. (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Go to the next step.
6		No	Go to the next step.
7	VERIFY AFTER REPAIR PROCEDURE Perform the "AFTER REPAIR PROCEDURE". (See AFTER REPAIR PROCEDURE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .) Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [PCM (SKYACTIV-G 2.0, SKYACTIV-G 2.5)] .)
7		No	DTC troubleshooting completed.