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	INSPECT IF MALFUNCTION CAUSE IS START STOP UNIT OR FRONT BODY CONTROL MODULE (FBCM) Display the start stop unit PID WIP_F_LOW using the M-MDS. (See PID/DATA MONITOR INSPECTION [START STOP UNIT] .) Verify the PID while operating the windshield wiper switch. Is the PID displayed normally?	Yes	Go to Step 3.
1		No	Go to the next step.
2	INSPECT WINDSHIELD WIPER SWITCH Inspect the windshield wiper switch. (See WIPER AND WASHER SWITCH INSPECTION .) Is the windshield wiper switch normal?	Yes	Replace the start stop unit, then go to Step 7. (See START STOP UNIT REMOVAL/INSTALLATION .)
2		No	Replace the wiper and washer switch, then go to Step 7. (See WIPER AND WASHER SWITCH REMOVAL/INSTALLATION .)
3	INSPECT IF MALFUNCTION CAUSE IS FRONT BODY CONTROL MODULE (FBCM) OR WIRING HARNESS Display the front body control module (FBCM) PID WIP_F using the M-MDS. (See PID/DATA MONITOR INSPECTION [FRONT BODY CONTROL MODULE (FBCM)] .) Verify the PID while operating the windshield wiper switch. Is the PID displayed normally?	Yes	Go to the next step.
3		No	Perform the CAN malfunction diagnosis flow and inspect the CAN for a malfunction. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW .) If there is no malfunction in the CAN, replace the front body control module (FBCM), then go to Step 7. (See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION .)
4	INSPECT FOR SHORT TO GROUND IN WIRING HARNESS BETWEEN START STOP UNIT AND FRONT BODY CONTROL MODULE (FBCM) Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Disconnect the front body control module (FBCM) connector. Disconnect the start stop unit connector. Inspect for continuity between front body control module (FBCM) terminal 2Y (wiring harness-side) and body ground. Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between start stop unit terminal 1V and front body control module (FBCM) terminal 2Y. 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. Go to Step 7.
4		No	Go to the next step.
5	INSPECT FOR SHORT TO POWER SUPPLY IN WIRING HARNESS BETWEEN START STOP UNIT AND FRONT BODY CONTROL MODULE (FBCM) Verify that the front body control module (FBCM) and start stop unit connectors are disconnected. Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Switch the ignition ON (engine off or on). Measure the voltage at the front body control module (FBCM) terminal 2Y (wiring harness-side). Is the voltage 0 V?	Yes	Go to the next step.
5		No	Refer to the wiring diagram and verify whether or not there is a common connector between start stop unit terminal 1V and front body control module (FBCM) terminal 2Y. 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 7.
6	INSPECT FOR OPEN CIRCUIT IN WIRING HARNESS BETWEEN START STOP UNIT AND FRONT BODY CONTROL MODULE (FBCM) Verify that the front body control module (FBCM) and start stop unit connectors are disconnected. Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Inspect for continuity between start stop unit terminal 1V (wiring harness-side) and front body control module (FBCM) terminal 2Y (wiring harness-side). Is there continuity?	Yes	Go to the next step.
6		No	Refer to the wiring diagram and verify whether or not there is a common connector between start stop unit terminal 1V and front body control module (FBCM) terminal 2Y. 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 the next step.
7	VERIFY THAT REPAIRS HAVE BEEN COMPLETED Always reconnect all disconnected connectors. Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Clear the front body control module (FBCM) DTCs using the M-MDS. (See CLEARING DTC [FRONT BODY CONTROL MODULE (FBCM)] .) Switch the ignition ON (engine off or on) and wait for 5 s or more. Retrieve the front body control module (FBCM) DTCs using the M-MDS. (See DTC INSPECTION [FRONT BODY CONTROL MODULE (FBCM)] .) Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the front body control module (FBCM). (See FRONT BODY CONTROL MODULE (FBCM) REMOVAL/INSTALLATION .) Go to the next step.
7		No	Go to the next step.
8	VERIFY IF OTHER DTCs DISPLAYED Are any other DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [FRONT BODY CONTROL MODULE (FBCM)] .)
8		No	DTC troubleshooting completed.