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DTC B1258:71 [DASH-ELECTRICAL SUPPLY UNIT]

id0702k8012500

Outline

System malfunction location

Rear vent actuator motor lock

Detection condition

•  The dash-electrical supply unit detects that the rear vent actuator remains operating clockwise or counterclockwise and does not stop for 8 s or more.

Fail-safe

•  Rear vent actuator drive signal is stopped right when the malfunction is determined.

Possible cause

•  Rear vent actuator malfunction

•  A/C unit malfunction

―  Rear vent link set malfunction

―  Rear vent door malfunction

•  Dash-electrical supply unit malfunction

System wiring diagram

Not applicable

Connector diagram

Not applicable

System malfunction location	Rear vent actuator motor lock
Detection condition	• The dash-electrical supply unit detects that the rear vent actuator remains operating clockwise or counterclockwise and does not stop for 8 s or more.
Fail-safe	• Rear vent actuator drive signal is stopped right when the malfunction is determined.
Possible cause	• Rear vent actuator malfunction • A/C unit malfunction ― Rear vent link set malfunction ― Rear vent door malfunction • Dash-electrical supply unit malfunction
System wiring diagram	Not applicable
Connector diagram	Not applicable

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY OTHER DTCs RELATED TO REAR VENT ACTUATOR INTERNAL POTENTIOMETER CIRCUIT

•  Perform the DTC inspection for the dash-electrical supply unit.
(See DTC INSPECTION.)

•  Are other DTCs related to the rear vent actuator internal potentiometer circuit displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

(See DTC TABLE [DASH-ELECTRICAL SUPPLY UNIT (E)].)

No

Go to the next step.

2

INSPECT REAR VENT ACTUATOR FOR MALFUNCTION

•  Perform the actuator inspection.
(See REAR VENT ACTUATOR INSPECTION [MANUAL AIR CONDITIONER].)

(See REAR VENT ACTUATOR INSPECTION [FULL-AUTO AIR CONDITIONER].)

•  Is the part normal?

Yes

Go to the next step.

No

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

(See REAR VENT ACTUATOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].)

(See REAR VENT ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)

3

INSPECT REAR VENT LINK SET OPERATION

•  Operate the rear vent link set manually.

•  Does the rear vent link set operate smoothly?

Yes

Go to the next step.

No

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

(See A/C UNIT REMOVAL/INSTALLATION [(E)].)

(See A/C UNIT DISASSEMBLY/ASSEMBLY [(E)].)

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.)

•  Switch the ignition ON (engine off or on) and wait for 8 s or more.

•  Perform the DTC inspection for the dash-electrical supply 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 dash-electrical supply unit, then go to the next step.
(See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)

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.

Step	Inspection	Results	Action
1	VERIFY OTHER DTCs RELATED TO REAR VENT ACTUATOR INTERNAL POTENTIOMETER CIRCUIT • Perform the DTC inspection for the dash-electrical supply unit. (See DTC INSPECTION.) • Are other DTCs related to the rear vent actuator internal potentiometer circuit displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting. (See DTC TABLE [DASH-ELECTRICAL SUPPLY UNIT (E)].)
1		No	Go to the next step.
2	INSPECT REAR VENT ACTUATOR FOR MALFUNCTION • Perform the actuator inspection. (See REAR VENT ACTUATOR INSPECTION [MANUAL AIR CONDITIONER].) (See REAR VENT ACTUATOR INSPECTION [FULL-AUTO AIR CONDITIONER].) • 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 REAR VENT ACTUATOR REMOVAL/INSTALLATION [MANUAL AIR CONDITIONER].) (See REAR VENT ACTUATOR REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)
3	INSPECT REAR VENT LINK SET OPERATION • Operate the rear vent link set manually. • Does the rear vent link set operate smoothly?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See A/C UNIT REMOVAL/INSTALLATION [(E)].) (See A/C UNIT DISASSEMBLY/ASSEMBLY [(E)].)
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.) • Switch the ignition ON (engine off or on) and wait for 8 s or more. • Perform the DTC inspection for the dash-electrical supply 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 dash-electrical supply unit, then go to the next step. (See DASH-ELECTRICAL SUPPLY UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER (E)].)
Repair completion verification 1		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.
Repair completion verification 2		No	DTC troubleshooting completed.