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 POROCEDURE

STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA HAS BEEN RECORDED Has the FREEZE FRAME DATA (Mode 2)/snapshot data been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA (Mode 2)/snapshot data on the 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 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)] .)
3		No	Go to the next step.
4	INSPECT EXHAUST CMP SENSOR CONNECTOR CONDITION Switch the ignition off. Disconnect the exhaust CMP sensor connector. Inspect for poor connection (such as damaged/pulled-out pins, corrosion). Is there any malfunction?	Yes	Repair or replace the connector and/or terminals, then go to Step 15.
4		No	Go to the next step.
5	INSPECT EXHAUST CMP SENSOR POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT Verify that the exhaust CMP sensor connector is disconnected. Switch the ignition ON (engine off). NOTE: Another DTC may be stored by the PCM detecting an open circuit. Measure the voltage at the exhaust CMP sensor terminal C (wiring harness-side). Is the voltage B+?	Yes	Go to the next step.
5		No	Inspect the ENGINE2 15 A fuse. If the fuse is blown: Refer to the wiring diagram and verify whether or not there is a common connector between ENGINE2 15 A fuse and exhaust CMP sensor terminal C. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to ground. Replace the fuse. If the fuse is damaged: Replace the fuse. If the fuse is normal: Refer to the wiring diagram and verify whether or not there is a common connector between main relay terminal D and exhaust CMP sensor terminal C. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has an open circuit. Go to Step 15.
6	INSPECT EXHAUST CMP SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND Verify that the exhaust CMP sensor connector is disconnected. Switch the ignition off. Inspect for continuity between exhaust CMP sensor terminal A (wiring harness-side) and body ground. Is there continuity?	Yes	If the short to ground circuit could be detected in the wiring harness: Refer to the wiring diagram and verify whether or not there is a common connector between exhaust CMP sensor terminal A and PCM terminal 1T. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to ground. If the short to ground circuit could not be detected in the wiring harness: Replace the PCM (short to ground in the PCM internal circuit). (See PCM REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Go to Step 15.
6		No	Go to the next step.
7	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 connector and/or terminals, then go to Step 15.
7		No	Go to the next step.
8	INSPECT EXHAUST CMP SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY Verify that the exhaust CMP sensor and PCM connectors are disconnected. Switch the ignition ON (engine off). NOTE: Another DTC may be stored by the PCM detecting an open circuit. Measure the voltage at the exhaust CMP sensor terminal A (wiring harness-side). Is the voltage 0 V?	Yes	Go to the next step.
8		No	Refer to the wiring diagram and verify whether or not there is a common connector between exhaust CMP sensor terminal A and PCM terminal 1T. If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to power supply. Go to Step 15.
9	INSPECT EXHAUST CMP SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER Verify that the exhaust CMP sensor and PCM connectors are disconnected. Switch the ignition off. Inspect for continuity between exhaust CMP sensor terminals A and B (wiring harness-side). Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: Exhaust CMP sensor terminal A-PCM terminal 1T Exhaust CMP sensor terminal B-PCM terminal 1X If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to each other. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has a short to each other. Go to Step 15.
9		No	Go to the next step.
10	INSPECT EXHAUST CMP SENSOR CIRCUIT FOR OPEN CIRCUIT Verify that the exhaust CMP sensor and PCM connectors are disconnected. Inspect for continuity between the following terminals (wiring harness-side): Exhaust CMP sensor terminal A-PCM terminal 1T Exhaust CMP sensor terminal B-PCM terminal 1X Is there continuity?	Yes	Go to the next step.
10		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: Exhaust CMP sensor terminal A-PCM terminal 1T Exhaust CMP sensor terminal B-PCM terminal 1X If there is a common connector: Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has an open circuit. Go to Step 15.
11	INSPECT EXHAUST CMP SENSOR Inspect the exhaust CMP sensor. (See CAMSHAFT POSITION (CMP) SENSOR INSPECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Is there any malfunction?	Yes	Replace the exhaust CMP sensor, then go to Step 15. (See CAMSHAFT POSITION (CMP) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
11		No	Go to the next step.
12	INSPECT CKP SENSOR CONNECTOR CONDITION Switch the ignition off. 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 connector and/or terminals, then go to Step 15.
12		No	Go to the next step.
13	INSPECT CKP SENSOR Inspect the CKP sensor. (See CRANKSHAFT POSITION (CKP) SENSOR INSPECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Is there any malfunction?	Yes	Replace the CKP sensor, then go to Step 15. (See CRANKSHAFT POSITION (CKP) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
13		No	Go to the next step.
14	VERIFY ASSEMBLY CONDITION OF TIMING CHAIN Verify the condition of the timing chain assembly (exhaust valve timing, looseness, jumping). (See TIMING CHAIN REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Is there any malfunction?	Yes	Repair or replace the malfunctioning part. Assemble the timing chain using the correct timing, then go to the next step. (See TIMING CHAIN REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
14		No	Go to the next step.
15	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 race it. Perform the KOER self test. (See KOEO/KOER SELF 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.
15		No	Go to the next step.
16	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)] .)
16		No	DTC troubleshooting completed.