System malfunction location

Mazda radar cruise control (MRCC) system operation malfunction

Detection condition

• The MRCC brake is operated excessively

Fail-safe

• Inhibits the Mazda radar cruise control (MRCC) system control

• Inhibits the forward obstruction warning (FOW) system control

Possible cause

• Accelerator pedal was operated repeatedly while driving using MRCC

• Dirt on radiator grille ornament, modifications, application of stickers (including transparent types), scratches, or damage

• Dirt on radar sensor, scratches, or damage

• Impact is transmitted to area around radar sensor

• Incorrect installation of radar sensor

• Radar sensor aiming adjustment error

• Radar sensor malfunction

• DSC HU/CM malfunction

• SAS control module malfunction

• Signal error in circuit between radar sensor and vehicle control module (V/C-module)

• Vehicle control module (V/C-module) malfunction

System wiring diagram

• Not applicable

Step

Inspection

Action

1

• Visually inspect the surface of the radiator grille ornament.

• Under the following conditions?

• Dirt is adhering to radiator grille ornament.

• Foreign matter (reflective object) is adhering to radiator grille ornament

• Radiator grille ornament is scratched or damaged

Yes

Return the surfaces of the radiator grille ornament to their normal condition, then go to Step 7.

No

Go to the next step.

2

• Remove front bumper.

  (See FRONT BUMPER REMOVAL/INSTALLATION.)

• Visually inspect the surface of the radar sensor.

• Under the following conditions?

• Dirt is adhering to radar sensor

• Foreign matter (reflective object) is adhering to radar sensor

• Radar sensor is scratched or damaged

Yes

Return the radar sensor to their normal condition, then go to Step 7.

No

Go to the next step.

3

• Verify that there is no bending or damage on the radar sensor bracket.

• Is there bending or damage on the radar sensor bracket?

Yes

Go to the next step.

No

Replace the radar sensor bracket and perform the aiming adjustment.

(See RADAR SENSOR DISASSMBLY/ASSEMBLY [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM].)

(See RADAR SENSOR AIMING [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM].)

Then go to Step 7.

4

• Perform the DSC HU/CM DTC inspection using the M-MDS.

  (See ON-BOARD DIAGNOSIS [DYNAMIC STABILITY CONTROL (DSC)].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See ON-BOARD DIAGNOSIS [DYNAMIC STABILITY CONTROL (DSC)].)

Then go to Step 7.

No

Go to the next step.

5

• Perform the SAS control module DTC inspection using the M-MDS.

  (See DTC INSPECTION [STANDARD DEPLOYMENT CONTROL SYSTEM].)

  (See DTC INSPECTION [TWO-STEP DEPLOYMENT CONTROL SYSTEM].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [STANDARD DEPLOYMENT CONTROL SYSTEM].)

(See DTC TABLE [TWO-STEP DEPLOYMENT CONTROL SYSTEM].)

Then go to Step 7.

No

Go to the next step.

6

• Clear vehicle control module (V/C-module) DTCs using the M-MDS.

  (See CLEARING DTC [VEHICLE CONTROL MODULE (V/C-MODULE)].)

• Switch the ignition ON (engine on).

• Perform the vehicle control module (V/C-module) DTC inspection using the M-MDS.

  (See DTC INSPECTION [VEHICLE CONTROL MODULE (V/C-MODULE)].)

• Are any DTCs present?

Yes

Go to the applicable DTC inspection.

(See DTC TABLE [VEHICLE CONTROL MODULE (V/C-MODULE)].)

Then go to the next step.

No

Go to the next step.

7

• Clear vehicle control module (V/C-module) DTCs using the M-MDS.

  (See CLEARING DTC [VEHICLE CONTROL MODULE (V/C-MODULE)].)

• Switch the ignition ON (engine on).

• Perform the vehicle control module (V/C-module) DTC inspection using the M-MDS.

  (See DTC INSPECTION [VEHICLE CONTROL MODULE (V/C-MODULE)].)

• Is the same DTC present?

Yes

Repeat the inspection from Step 1.

• If the malfunction does not recur, go to the next step.

• If the malfunction recurs, replace the vehicle control module (V/C-module).

  (See VEHICLE CONTROL MODULE (V/C-MODULE) REMOVAL/INSTALLATION [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM].)

Go to the next step.

No

Go to the next step.

8

• Verify other DTCs displayed.

• Are any other DTCs output?

Yes

Perform the corresponding DTC inspection.

No

DTC troubleshooting completed.