VEHICLE SPEED CANNOT BE SET TO DESIRED SPEED [INTELLIGENT SPEED ASSISTANCE (ISA)]

id1503d8030600

Note

• Due to environmental effects, the system behavior may differ from the driver’s intentions even though the vehicle has no malfunction. To perform symptom troubleshooting, an understanding of the applicable system from the new vehicle instruction is required. For details on the control conditions of the system, refer to the [INTELLIGENT SPEED ASSISTANCE (ISA)] operation in the service highlights/technical guide.

Outline

Description

•  The vehicle speed cannot be set to the desired speed using the cruise control switch.

Possible cause

•  Cruise control switch malfunction

•  Forward sensing camera (FSC) malfunction

•  BCM malfunction

Diagnostic Procedure

Step

Inspection

Action

1

VERIFY ALL SYSTEM DTCs

•  Perform the DTC inspection.
(See DTC INSPECTION.)

•  Are any DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

Go to the next step.

2

INSPECT CRUISE CONTROL SWITCH FOR MALFUNCTION

•  Inspect the applicable part.
(See CRUISE CONTROL SWITCH INSPECTION [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM].)

•  Is the part normal?

Yes

Go to the next step.

No

Repair or replace the malfunctioning location and perform the repair completion verification.

(See CRUISE CONTROL SWITCH REMOVAL/INSTALLATION [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM].)

Repair completion verification

VERIFY THAT VEHICLE IS REPAIRED

•  Install/connect the part removed/disconnected during the troubleshooting procedure.

•  Has the malfunction symptom been eliminated?

Yes

Complete the symptom troubleshooting. (Explain contents of repair to customer)

No

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 is not resolved, replace the BCM.
(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.)

Description	• The vehicle speed cannot be set to the desired speed using the cruise control switch.
Possible cause	• Cruise control switch malfunction • Forward sensing camera (FSC) malfunction • BCM malfunction

Step	Inspection		Action
1	VERIFY ALL SYSTEM DTCs • Perform the DTC inspection. (See DTC INSPECTION.) • Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
1		No	Go to the next step.
2	INSPECT CRUISE CONTROL SWITCH FOR MALFUNCTION • Inspect the applicable part. (See CRUISE CONTROL SWITCH INSPECTION [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM].) • Is the part normal?	Yes	Go to the next step.
2		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See CRUISE CONTROL SWITCH REMOVAL/INSTALLATION [MAZDA RADAR CRUISE CONTROL (MRCC) SYSTEM].)
Repair completion verification	VERIFY THAT VEHICLE IS REPAIRED • Install/connect the part removed/disconnected during the troubleshooting procedure. • Has the malfunction symptom been eliminated?	Yes	Complete the symptom troubleshooting. (Explain contents of repair to customer)
Repair completion verification		No	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 is not resolved, replace the BCM. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION.)