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	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.
1		No	Go to the next step.
2	INSPECT CAPACITOR (i-ELOOP) CONNECTOR CONDITION Switch the ignition off. Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Remove the service plug. (See SERVICE PLUG DISCONNECTION/CONNECTION [i-ELOOP] .) Disconnect the capacitor (i-ELOOP) 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 9.
2		No	Go to the next step.
3	INSPECT DC-DC CONVERTER CONNECTOR CONDITION Disconnect the DC-DC converter 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 9.
3		No	Go to the next step.
4	INSPECT CAPACITOR (i-ELOOP) TEMPERATURE SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND Verify that the capacitor (i-ELOOP) and DC-DC converter connectors are disconnected. Inspect for continuity between capacitor (i-ELOOP) terminal 1A (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 capacitor (i-ELOOP) terminal 1A and DC-DC converter terminal 1E. 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 9.
4		No	Go to the next step.
5	INSPECT CAPACITOR (i-ELOOP) TEMPERATURE SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER SUPPLY Verify that the capacitor (i-ELOOP) and DC-DC converter 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). Measure the voltage at the capacitor (i-ELOOP) terminal 1A (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 capacitor (i-ELOOP) terminal 1A and DC-DC converter terminal 1E. 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 9.
6	INSPECT CAPACITOR (i-ELOOP) TEMPERATURE SENSOR SIGNAL CIRCUIT AND GROUND CIRCUIT FOR SHORT TO EACH OTHER Verify that the capacitor (i-ELOOP) and DC-DC converter 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 capacitor (i-ELOOP) terminals 1A and 1B (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: Capacitor (i-ELOOP) terminal 1A-DC-DC converter terminal 1E Capacitor (i-ELOOP) terminal 1B-DC-DC converter terminal 1D 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 9.
6		No	Go to the next step.
7	INSPECT CAPACITOR (i-ELOOP) TEMPERATURE SENSOR CIRCUIT FOR OPEN CIRCUIT Verify that the capacitor (i-ELOOP) and DC-DC converter connectors are disconnected. Inspect for continuity between the following terminals (wiring harness-side): Capacitor (i-ELOOP) terminal 1A-DCDC converter terminal 1E Capacitor (i-ELOOP) terminal 1B-DC-DC converter terminal 1D Is there continuity?	Yes	Go to the next step.
7		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: Capacitor (i-ELOOP) terminal 1A-DC-DC converter terminal 1E Capacitor (i-ELOOP) terminal 1B-DC-DC converter terminal 1D 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 9.
8	INSPECT CAPACITOR (i-ELOOP) TEMPERATURE SENSOR Inspect the capacitor (i-ELOOP) temperature sensor. (See CAPACITOR (i-ELOOP) INSPECTION [i-ELOOP] .) Is there any malfunction?	Yes	Replace the capacitor (i-ELOOP), then go to the next step. (See CAPACITOR (i-ELOOP) REMOVAL/INSTALLATION [i-ELOOP] .)
8		No	Go to the next step.
9	VERIFY DTC TROUBLESHOOTING 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] .) Reinstall the service plug. (See SERVICE PLUG DISCONNECTION/CONNECTION [i-ELOOP] .) Clear the DTC for the DC-DC converter using the M-MDS. (See CLEARING DTC [i-ELOOP] .) Switch the ignition off. Switch the ignition ON (engine on) and wait for 1 s or more. Retrieve the DC-DC converter DTCs using the M-MDS. (See DTC INSPECTION [i-ELOOP] .) Is the same DTC present?	Yes	Repeat the inspection from Step 1. If the malfunction recurs, replace the DCDC converter. (See DC-DC CONVERTER REMOVAL/INSTALLATION [i-ELOOP] .) Go to the next step.
9		No	Go to the next step.
10	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 [i-ELOOP] .)
10		No	DTC troubleshooting completed.