Troubleshooting Diagnostic Procedure

WARNING: This page is about a different car, the 2016 Mazda CX-5. However, it is still accessible from the selected car via links, so may be relevant.

Intention of troubleshooting procedure

Step 1-3
- Perform an inspection of the A/F sensor and PCM-related connectors and wiring harnesses.
Step 4
- Perform a unit inspection of the A/F sensor.
Step 5-6
- Verify that the primary malfunction is resolved and there are no other malfunctions.

STEP	INSPECTION	RESULTS	ACTION
1	PURPOSE: INSPECT A/F SENSOR CONNECTOR CONDITION Switch the ignition off. Disconnect the A/F 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 5.
1		No	Go to the next step.
2	PURPOSE: 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 5.
2		No	Go to the next step.
3	PURPOSE: INSPECT A/F SENSOR CIRCUIT FOR OPEN CIRCUIT Verify that the A/F sensor and PCM connectors are disconnected. Inspect for continuity between A/F sensor terminal B (wiring harness-side) and PCM terminal 1AG (wiring harness-side). Is there continuity?	Yes	Go to the next step.
3		No	Refer to the wiring diagram and verify whether or not there is a common connector between A/F sensor terminal B and PCM terminal 1AG. 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 5.
4	PURPOSE: DETERMINE INTEGRITY OF A/F SENSOR Start the engine and warm it up completely. Access the O2S11 PID using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Drive the vehicle under the following conditions. WARNING: 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. While performing this step, always operate the vehicle in a safe and lawful manner. After increasing the engine speed to 3, 000 rpm, decelerate using engine braking. Is the displayed PID value as follows? O2S11: 0.25 mA or more	Yes	Go to the next step.
4		No	Replace the A/F sensor, then go to the next step. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
5	PURPOSE: VERIFICATION OF VEHICLE REPAIR COMPLETION Always reconnect all disconnected connectors. Clear the DTC from the PCM memory using the M-MDS. (See CLEARING DTC [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Perform the KOER self test. (See KOEO/KOER SELF TEST [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Is the PENDING CODE for this 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.
5		No	Go to the next step.
6	PURPOSE: VERIFY IF THERE IS ANY OTHER MALFUNCTION Is any other DTC or pending code stored?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
6		No	DTC troubleshooting completed.