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Home >> Mazda >> 2019 >> 3 Base, 4D Hatchback, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Communication Devices >> On-Board Diagnostic - Body Control Module (BCM) (2 Of 2) >> DTC U2100-56: LF Control Unit Configuration Error (BCM) >> Diagnostic Procedure
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Diagnostic Procedure

DTC U2100:56 (BCM) DIAGNOSTIC PROCEDURE

Step Inspection Results Action
1 VERIFY BODY CONTROL MODULE (BCM) DTCs AGAIN
  • Clear the DTC recorded in the memory. (See CLEARING DTC .)
  • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION .)
  • Is the same Pending DTC present?
Yes Go to the next step.
No Go to repair completion verification 2.
2 RESET CONFIGURATION DATA FOR LF CONTROL UNIT
  • Using the M-MDS, perform the LF control unit configuration. (See CONFIGURATION .)
  • Clear the DTC recorded in the memory. (See CLEARING DTC .)
  • Perform the DTC inspection for the body control module (BCM). (See DTC INSPECTION .)
  • Is the same Pending DTC present?
Yes Replace LF control unit and perform the repair completion verification.
(See LF CONTROL UNIT REMOVAL/INSTALLATION .)
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 body control module (BCM). (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.
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.