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 B2009:23 [DASH-ELECTRICAL SUPPLY UNIT] DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	VERIFY THAT CLIMATE CONTROL UNIT OPERATION PANEL IS STUCK ON Select the following PIDs according to the vehicle specification. (See PID/DATA MONITOR INSPECTION .) (See PID/DATA MONITOR TABLE [CLIMATE CONTROL UNIT (MANUAL AIR CONDITIONER) (US)] .) (See PID/DATA MONITOR TABLE [CLIMATE CONTROL UNIT (FULL-AUTO AIR CONDITIONER) (US)] .) Climate control unit (manual air conditioner) A/C_MODE_BILVL_SW A/C_MODE_FLOOR_DEF_SW A/C_MODE_FLOOR_SW A/C_MODE_PNL_SW A/C_SW (With refrigerant system) DEF_SW R_DEF_SW REC_SW SEAT_HEAT_SW_L (With seat warmer system) SEAT_HEAT_SW_R (With seat warmer system) STR_HEAT_SW (With heated steering wheel system) Climate control unit (full-auto air conditioner) A/C_SW AUTO_SW DEF_SW FAN_DOWN_SW FAN_UP_SW MODE_SW ON_OFF_SW R_DEF_SW REC_SW SEAT_HEAT_SW_L (With seat warmer system) SEAT_HEAT_SW_R (With seat warmer system) STR_HEAT_SW (With heated steering wheel system) SYNC_SW Operate the switches located on the climate control unit operation panel and verify if the corresponding PID item display changes according to the operation. Is the operation for all the switches in conjunction with the PID item display?	Yes	Go to the next step.
1		No	Replace the climate control unit and perform the repair completion verification. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (US)] .) (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (US)] .)
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 dash-electrical supply unit. (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 dash-electrical supply unit, then go to the next step. (See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER (US)] .) (See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (US)] .)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTCs DISPLAYED Perform the DTC inspection. (See DTC INSPECTION .) Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.