DTC U2511:68 [VEHICLE CONTROL MODULE]

id1502c5038000

Warning

<<High voltage>>

•  Always observe the following thoroughly to ensure safety when inspecting or removing/installing parts in the motor compartment. Otherwise, the high voltage circuit may operate on the vehicle regardless of whether or not the main power is switched OFF or ON (READY off or on). If this occurs, it could cause electrical shock and result in serious injury or, in the worst case, death.

―  Do not select high voltage battery cooling on center display after EV system stops

―  Do not open/close doors frequently with main power switched OFF

―  Do not perform normal charging or quick charging

―  Switch to connected vehicle maintenance mode (MyMazda App connected vehicle)

―  Cancel climate control timer

―  Operate center display and turn off battery heater operation

Warning

•  The cooling fan may suddenly start operating regardless of the main power switch position. Keep hands and tools away from the cooling fan even if the cooling fan is not operating to prevent injury, or damage to the cooling fan. When servicing the cooling fan or parts near the cooling fan, ensure the following.

―  Do not perform normal charging or quick charging

―  Do not select high voltage battery cooling on center display after EV system stops

―  Do not open/close doors frequently with main power switched OFF

―  Switch to connected vehicle maintenance mode (MyMazda App connected vehicle)

―  Cancel climate control timer

―  Operate center display and turn off battery heater operation

Outline

System malfunction location	Brake light control signal error
Detection condition	•  The vehicle control module (VCM) detects an error in the brake light illumination request signal received from the electronically controlled brake unit or the brake light illumination condition signal received from the electrical supply unit (ESU) for 5 s. Preconditions •  During brake pedal operation
Fail-safe	(See DTC TABLE [VEHICLE CONTROL MODULE (E)].)
Possible cause	•  Electrical supply unit (ESU) malfunction ―  Brake light illumination condition signal error •  Electronically controlled brake unit malfunction ―  Brake light illumination request signal error •  Vehicle control module (VCM) malfunction (built into body control module (BCM)) •  Body control module (BCM) malfunction
System wiring diagram	Not applicable
Connector diagram	Not applicable

Diagnostic Procedure

Step	Inspection	Results	Action
1	INSPECT VEHICLE CONTROL MODULE (VCM) AND BODY CONTROL MODULE (BCM) FOR MALFUNCTION •  Perform the DTC inspection for the vehicle control module (VCM) and the body control module (BCM). (See DTC INSPECTION.) •  Is a DTC related to an internal malfunction displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [VEHICLE CONTROL MODULE (E)].) (See DTC TABLE [BODY CONTROL MODULE (BCM) (E)].)
		No	Go to the next step.
2	VERIFY ELECTRICAL SUPPLY UNIT (ESU) DTCs •  Perform the DTC inspection for the electrical supply unit (ESU). (See DTC INSPECTION.) •  Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [BODY CONTROL MODULE (BCM) (E)].)
		No	Go to the next step.
3	VERIFY ELECTRONICALLY CONTROLLED BRAKE UNIT DTCs •  Perform the DTC inspection for electronically controlled brake unit. (See DTC INSPECTION.) •  Is a DTC displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)
		No	Go to the next step.
4	INSPECT ELECTRICAL SUPPLY UNIT (ESU) FOR MALFUNCTION DEPENDING ON REPEATABILITY •  Install/connect the part removed/disconnected during the troubleshooting procedure. •  Clear the DTC recorded in the memory. (See CLEARING DTC.) •  Switch the main power ON (READY off or on) and wait for 5 s or more. •  Perform the DTC inspection for the vehicle control module (VCM). (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 [L.H.D. (E)].) (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.].) If the CAN communication is normal, perform the diagnosis from Step 1. •  If the malfunction recurs, replace the electrical supply unit (ESU), then go to the next step. (See ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION.)
		No	Perform the “ACTION FOR NON-REPEATABLE MALFUNCTIONS”. (See TROUBLESHOOTING PROCEDURE [(E)].) If DTC is displayed: •  Repeat the diagnosis from Step 1. If DTC is not displayed: •  Go to repair completion verification 2.
5	INSPECT ELECTRONICALLY CONTROLLED BRAKE UNIT FOR MALFUNCTION DEPENDING ON REPEATABILITY •  Install/connect the part removed/disconnected during the troubleshooting procedure. •  Clear the DTC recorded in the memory. (See CLEARING DTC.) •  Switch the main power ON (READY off or on) and wait for 5 s or more. •  Perform the DTC inspection for the vehicle control module (VCM). (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 [L.H.D. (E)].) (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.].) If the CAN communication is normal, perform the diagnosis from Step 1. •  If the malfunction recurs, replace the electronically controlled brake unit, then go to the next step. (See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].) (See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [R.H.D.].)
		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.) •  Switch the main power ON (READY off or on) and wait for 5 s or more. •  Perform the DTC inspection for the vehicle control module (VCM). (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 [L.H.D. (E)].) (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [R.H.D.].) 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.)
		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTC IS DISPLAYED •  Perform the DTC inspection. (See DTC INSPECTION.) •  Are any other DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
		No	DTC troubleshooting completed.