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Diagnostic Procedure

DTC B14F1:78 [VEHICLE CONTROL MODULE] 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 (US)] .)
(See DTC TABLE [BODY CONTROL MODULE (BCM) (US)] .)
No Go to the next step.
2 INSPECT FRONT SIDE RADAR SENSOR (LH) FOR MALFUNCTION
  • Perform the DTC inspection for the front side radar sensor (LH). (See DTC INSPECTION .)
  • Is a DTC displayed?
 Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [FRONT SIDE RADAR SENSOR (US)] .)
No Go to the next step.
3 INSPECT FRONT SIDE RADAR SENSOR (RH) FOR MALFUNCTION
  • Perform the DTC inspection for the front side radar sensor (RH). (See DTC INSPECTION .)
  • Is a DTC displayed?
 Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [FRONT SIDE RADAR SENSOR (US)] .)
No Go to the next step.
4 VERIFY FRONT BUMPER CONDITION
  • Inspect the front side radar sensor installation surface of the front bumper for the following.
    • Damage (including repairs using putty application)
    • Dirt
    • Application of stickers (including transparent types)
    • Freezing
  • Is the front bumper condition normal?
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See FRONT BUMPER REMOVAL/INSTALLATION (US) .)
5 VERIFY IF FRONT BUMPER IS INSTALLED POORLY
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See FRONT BUMPER REMOVAL/INSTALLATION (US) .)
6 VERIFY IF FRONT SIDE RADAR SENSOR IS INSTALLED POORLY
 Yes Go to the next step.
No Repair or replace the malfunctioning location and perform the repair completion verification.
(See FRONT SIDE RADAR SENSOR REMOVAL/INSTALLATION .)
7 PERFORM FRONT SIDE RADAR SENSOR RADAR AIMING
 Yes Replace the front side radar sensor (RH), then go to the next step.
(See FRONT SIDE RADAR SENSOR REMOVAL/INSTALLATION .)
No Go to repair completion verification 2.
8 INSPECT FRONT SIDE RADAR SENSOR (LH) 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 .)
  • 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 (US) .)
If the CAN communication is normal, replace the front side radar sensor (LH) and perform the repair completion verification.
(See FRONT SIDE RADAR SENSOR 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 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 (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.
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