Diagnostic Procedure

WARNING: This page is about a different car, the 2017 Mazda CX-9. However, it is still accessible from the selected car via links, so may be relevant.

DIAGNOSTIC PROCEDURE

Step	Inspection		Action
1	VERIFY EPS CONTROL MODULE DTC Using the M-MDS, perform the EPS control module DTC inspection. (See DTC INSPECTION [ELECTRIC POWER STEERING (EPS)] .) Are any DTCs present?	Yes	Go to applicable DTC inspection. (See DTC TABLE [ELECTRIC POWER STEERING (EPS)] .) DTC troubleshooting completed, then go to the next step.
1		No	Go to the next step.
2	VERIFY DTC TROUBLESHOOTING COMPLETED Using the M-MDS, clear the DTC from the laser sensor. (See CLEARING DTC [LASER SENSOR] .) Using the M-MDS, perform the laser sensor DTC inspection. (See DTC INSPECTION [LASER SENSOR] .) Is the same DTC present?	Yes	Perform the following procedures: Verify that the steering angle sensor is equipped, and its wiring harness connects with start stop unit (See STEERING ANGLE SENSOR REMOVAL/INSTALLATION .) Using the M-MDS, select the PID item STR_AB_EST for EPS control module. Verify the monitor value with steering wheel position 0 ° (vehicle wheels straight-ahead). If monitor value is ± 20 ° or less, replace the steering column, then go to the next step. (See STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION .) If monitor value is ± 20 ° or more, verify that the master warning light blacks out when vehicle is driven for approx. 5 min after the steering angle signal is reset. (See START STOP UNIT CONFIGURATION (USING AS-BUILT DATA) .) If the malfunction recurs, replace the steering column, then go to the next step. (See STEERING WHEEL AND COLUMN REMOVAL/INSTALLATION .)
2		No	Go to the next step.
3	VERIFY NO DTC IS PRESENT Are any DTCs present?	Yes	Go to applicable DTC inspection. (See DTC TABLE [LASER SENSOR] .)
3	VERIFY NO DTC IS PRESENT Are any DTCs present?	No	DTC troubleshooting completed.