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.

Step	Inspection		Action
1	INSPECT ACC RELAY FOR MALFUNCTION Switch the ignition to off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Remove the ACC relay. Inspect the ACC relay. (See RELAY INSPECTION .) Is the ACC relay normal?	Yes	Go to the next step.
1		No	Replace the ACC relay, then go to Step 7.
2	INSPECT ACC RELAY POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT OR SHORT TO GROUND Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Switch the ignition to ACC or ON (engine off or on). Measure the voltage at ACC relay terminal D (vehicle wiring harness side). Is the voltage B+?	Yes	Go to the next step.
2		No	Inspect the IG2 30 A fuse. If a fuse is burnt out: Repair or replace the wiring harness which is shorted to ground. Replace the fuse. If a fuse is damaged: Replace the fuse. If the fuse is normal: Repair or replace the wiring harness which has an open circuit. Go to Step 7.
3	INSPECT START STOP UNIT CONNECTOR CONDITION Switch the ignition to off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Disconnect the start stop unit connector. Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. Is the connector normal?	Yes	Go to the next step.
3		No	Repair or replace the connector, then go to Step 7.
4	INSPECT MIRROR 7.5A FUSE Remove the MIRROR 7.5A fuse. Inspect the MIRROR 7.5A fuse. Is the MIRROR 7.5A fuse normal?	Yes	If the fuse is blown: Repair or replace the wiring harness for a possible short to ground. Replace the fuse. If the fuse is deteriorated: Replace the fuse. Go to Step 7.
4		No	Reinstall the MIRROR 7.5A fuse, then go to the next step.
5	INSPECT ACC RELAY CIRCUIT FOR SHORT TO GROUND Verify that the start stop unit disconnected. Inspect for continuity start stop unit terminal 1E (vehicle wiring harness side) and body ground. Is there continuity?	Yes	Repair or replace the wiring harness which is shorted to ground, then go to Step 7.
5		No	Go to the next step.
6	INSPECT ACC RELAY CIRCUIT FOR OPEN CIRCUIT IG1 relay is removed. Verify that the start stop unit connector is disconnected. Inspect the wiring harness for continuity between ACC relay terminal D (vehicle wiring harness side) and start stop unit terminal 1E (vehicle wiring harness side). Is there continuity?	Yes	Go to the next step.
6		No	Repair or replace the wiring harness which has an open circuit, then go to the next step.
7	VERIFY THAT REPAIRS HAVE BEEN COMPLETED Reconnect all the disconnected connectors. Reconnect the disconnected negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Clear DTC for the start stop unit using the M-MDS. (See CLEARING DTC [START STOP UNIT] .) Switch the ignition to ACC or ON (engine off or on) and wait for 1 s or more . Perform the DTC inspection for the start stop unit using the M-MDS. (See DTC INSPECTION [START STOP UNIT] .) Is the DTC U3004:16 displayed?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the start stop unit, then go to the next step. (See START STOP UNIT REMOVAL/INSTALLATION .)
7		No	Go to the next step.
8	VERIFY IF OTHER DTCs DISPLAYED Are any other DTCs displayed?	Yes	Repair the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [START STOP UNIT] .)
8		No	DTC troubleshooting completed.