Mazdamanuals.com

DTC U3003:68 [ELECTRONICALLY CONTROLLED BRAKE UNIT]

Home  id0402c6014200

Outline

System malfunction location	Power supply system
Detection condition	•  The electronically controlled brake unit shuts down while the electric parking brake motor gear unit is operating.
Fail-safe	Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”. (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)
Possible cause	•  DTCs are stored in the following modules. ―  PCM ―  Mazda M Hybrid battery ―  DC-DC converter (Mazda M Hybrid) ―  Integrated starter generator (ISG) •  Battery malfunction •  Electronically controlled brake unit connector or terminals malfunction •  Short to ground or open circuit in electronically controlled brake unit power supply circuit •  Open circuit in electronically controlled brake unit ground circuit •  Electronically controlled brake unit malfunction

Diagnostic Procedure

Step	Inspection	Results	Action
1	VERIFY OPERATION CONDITION BY CUSTOMER •  Verify if the customer switched the ignition OFF while pulling up/pressing down the electric parking brake switch. •  Did the customer switch the ignition OFF while pulling up/pressing down the electric parking brake switch?	Yes	The system is normal. (Explain to the customer that switching the ignition OFF while pulling up/pressing down the electric parking brake switch was the cause of the DTC being displayed, and explain how to appropriately operate the switch.)
		No	Go to the next step.
2	VERIFY DTCs •  Perform the DTC inspection for the following modules. (See DTC INSPECTION.) ―  PCM ―  Mazda M Hybrid battery ―  DC-DC converter (Mazda M Hybrid) ―  Integrated starter generator (ISG) •  Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [PCM (SKYACTIV-G (E))].) (See DTC TABLE [PCM (SKYACTIV-X)].) (See DTC TABLE [Mazda M Hybrid BATTERY].) (See DTC TABLE [DC-DC CONVERTER (Mazda M Hybrid)].) (See DTC TABLE [INTEGRATED STARTER GENERATOR (ISG)].)
		No	Go to the next step.
3	INSPECT BATTERY FOR MALFUNCTION •  Inspect the applicable part. (See BATTERY INSPECTION [(E)].) •  Is the part normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See BATTERY RECHARGING [(E)].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITHOUT CYLINDER DEACTIVATION (E))].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G (WITH CYLINDER DEACTIVATION (E))].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-X 2.0].)
4	INSPECT ELECTRONICALLY CONTROLLED BRAKE UNIT CONNECTOR FOR MALFUNCTION •  Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION.) •  Are the connector and terminal normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
5	INSPECT ELECTRONICALLY CONTROLLED BRAKE UNIT POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT •  Inspect the power supply circuit for an open circuit and short to ground. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
6	INSPECT ELECTRONICALLY CONTROLLED BRAKE UNIT GROUND CIRCUIT FOR OPEN CIRCUIT •  Inspect the applicable circuit for open circuit. (See CIRCUIT INSPECTION.) •  Is the circuit normal?	Yes	Go to the next step.
		No	Repair or replace the malfunctioning location and perform the repair completion verification.
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 electronically controlled brake 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 [(E)].) 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 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.
		No	DTC troubleshooting completed.