Diagnostic Procedure

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC U2301:56 (PARKING ASSIST UNIT (OPTICAL)) DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	INSPECT VEHICLE CONTROL MODULE (VCM) AND BODY CONTROL MODULE (BCM) FOR MALFUNCTION Switch the ignition OFF, and then switch it ON (engine off). Perform the DTC inspection for the vehicle control module (VCM) and the body control module (BCM). (See DTC INSPECTION .) Is a DTC related to a communication error or internal malfunction displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [VEHICLE CONTROL MODULE (US)] .) (See DTC TABLE [BODY CONTROL MODULE (BCM) (US)] .)
1		No	Go to the next step.
2	INSPECT PARKING ASSIST UNIT (OPTICAL) FOR MALFUNCTION Perform the DTC inspection for the parking assist unit (optical). (See DTC INSPECTION .) Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PARKING ASSIST UNIT (OPTICAL) (US)] .)
2		No	Go to the next step.
3	VERIFY PARKING ASSIST UNIT (OPTICAL) REPLACEMENT RECORD Verify if the parking assist unit (optical) has been replaced before performing this troubleshooting procedure. Has the parking assist unit (optical) been replaced?	Yes	After performing the procedure required for the parking assist unit (optical) replacement again, perform the repair completion verification according to the [PARKING ASSIST UNIT (OPTICAL) REMOVAL/INSTALLATION]. (See PARKING ASSIST UNIT (OPTICAL) REMOVAL/INSTALLATION (US) .)
3		No	Go to the next step.
4	VERIFY IF MALFUNCTION IS CAUSED BY BODY CONTROL MODULE (BCM) CONFIGURATION ERROR Switch the ignition OFF and wait for 30 s or more. Switch the ignition ON (engine off or on) and wait for 30 s or more. Clear the DTC recorded in the memory. (See CLEARING DTC .) Perform the DTC inspection for the parking assist unit (optical). (See DTC INSPECTION .) Is the same Pending DTC present?	Yes	Go to the next step.
4		No	Go to repair completion verification 2.
5	VERIFY BODY CONTROL MODULE (BCM) CONFIGURATION RELATED DTCs Clear the DTC recorded in the memory. (See CLEARING DTC .) Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION .) Is a configuration related DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [BODY CONTROL MODULE (BCM) (US)] .)
5		No	Go to the next step.
6	RESET BODY CONTROL MODULE (BCM) CONFIGURATION DATA Using the M-MDS, perform the body control module (BCM) configuration. (See CONFIGURATION .) Clear the DTC recorded in the memory. (See CLEARING DTC .) Perform the DTC inspection for the parking assist unit (optical). (See DTC INSPECTION .) Is the same Pending DTC present?	Yes	Replace the parking assist unit (optical) and perform the repair completion verification. (See PARKING ASSIST UNIT (OPTICAL) REMOVAL/INSTALLATION (US) .)
6		No	Go to repair completion verification 2.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED Install/connect the part removed/disconnected during the troubleshooting procedure. Clear the DTC recorded in the memory. (See CLEARING DTC .) Perform the DTC inspection for the parking assist unit (optical). (See DTC INSPECTION .) Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW (US) .) If the CAN communication is normal, perform the diagnosis from Step 1. If the malfunction recurs, replace the body control module (BCM), then go to the next step. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION (US) .)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTCs ARE DISPLAYED Perform the DTC inspection. (See DTC INSPECTION .) Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.