Diagnostic Procedure

WARNING: This page is about a different car, the 2014 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

DTC C1A67:04 (VEHICLE CONTROL MODULE) DIAGNOSTIC PROCEDURE

Step	Inspection		Action
1	PERFORM DTC INSPECTION FOR PCM Perform the PCM DTC inspection using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 2.5] .) Are any DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE [SKYACTIV-G 2.5] .) Then go to Step 6.
1		No	Go to the next step.
2	INSPECT FUSE Switch the ignition off (LOCK). Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.5] .) Remove the C/U IG1 15 A fuse. Is the fuse normal?	Yes	Install the C/U IG1 15 A fuse, then go to the next step.
2		No	Replace the C/U IG1 15 A fuse, then go to Step 6.
3	INSPECT BATTERY Inspect the battery. (See BATTERY INSPECTION [SKYACTIV-G 2.5] .) Is the battery normal?	Yes	Go to the next step.
3		No	Replace/charge the battery, then go to Step 6. (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G 2.5] .) (See BATTERY RECHARGING [SKYACTIV-G 2.5] .)
4	INSPECT WIRING HARNESS BETWEEN RADAR SENSOR AND IG1 RELAY Remove the front bumper. (See FRONT BUMPER REMOVAL/INSTALLATION .) Disconnect the radar sensor connector. Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.5] .) Switch the ignition ON (engine off or on). Measure the voltage of radar sensor terminal E (wiring harness-side). NOTE: Measure the voltage while shaking the wiring harness between the radar sensor and IG1 relay. Is the voltage between approx. 9.5-15.5 V ?	Yes	Go to the next step.
4		No	Refer to the wiring diagram and verify whether or not there is a common connector between radar sensor terminal E and IG1 relay. 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 or short to ground. Repair or replace the malfunctioning part. If there is no common connector: Repair or replace the wiring harness which has an open circuit or short to ground. Go to Step 6.
5	PERFORM DTC INSPECTION FOR VEHICLE CONTROL MODULE (V/C-MODULE) Connect the radar sensor connector. Connect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 2.5] .) Clear vehicle control module (V/C-module) DTCs using the M-MDS. (See CLEARING DTC [VEHICLE CONTROL MODULE (V/C-MODULE)] .) Switch the ignition ON (engine on). Perform the vehicle control module (V/C-module) DTC inspection using the M-MDS. (See DTC INSPECTION [VEHICLE CONTROL MODULE (V/C-MODULE)] .) Is the same DTC present?	Yes	Replace the radar sensor, then go to the next step. (See RADAR SENSOR REMOVAL/INSTALLATION [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM] .)
5		No	Go to the next step.
6	VERIFY THAT REPAIRS HAVE BEEN COMPLETED Clear vehicle control module (V/C-module) DTCs using the M-MDS. (See CLEARING DTC [VEHICLE CONTROL MODULE (V/C-MODULE)] .) Switch the ignition ON (engine on). Perform the vehicle control module (V/C-module) DTC inspection using the M-MDS. (See DTC INSPECTION [VEHICLE CONTROL MODULE (V/C-MODULE)] .) Is the same DTC present?	Yes	Repeat the inspection from Step 1. If the malfunction does not recur, go to the next step. If the malfunction recurs, replace the vehicle control module (V/C-module). (See VEHICLE CONTROL MODULE (V/C-MODULE) REMOVAL/INSTALLATION [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM] .) Go to the next step.
6		No	Go to the next step.
7	VERIFY THAT NO OTHER DTCs ARE PRESENT Verify other DTCs displayed. Are any other DTCs output?	Yes	Perform the corresponding DTC inspection.
7		No	DTC troubleshooting completed.