Description

Electrical supply unit (ESU) internal malfunction

Detection condition

• ROM malfunction in electrical supply unit (ESU) detected.

Fail-safe

Exterior lighting system

• When the ignition is switched ON (engine off or on), the headlights LO, TNS (parking lights), and panel light turn on and other exterior light controls are stopped.

Interior light control system

• Turn the interior light off when the room light switch is in the DOOR position.

Possible cause

• Electrical supply unit (ESU) malfunction

System wiring diagram

Not applicable

Step

Inspection

Action

1

• Clear the DTC for the electrical supply unit (ESU) using the M-MDS.

  (See CLEARING DTC [ELECTRICAL SUPPLY UNIT (ESU)].)

• Retrieve the electrical supply unit (ESU) DTCs using the M-MDS.

  (See DTC INSPECTION [ELECTRICAL SUPPLY UNIT (ESU)].)

• Is the same DTC displayed?

Yes

Replace the electrical supply unit (ESU), then go to the next step.

(See ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION.)

No

Go to the next step.

2

• Are any other DTCs displayed?

Yes

Repair or replace the malfunctioning part according to the applicable DTC troubleshooting.

(See DTC TABLE [ELECTRICAL SUPPLY UNIT (ESU)].)

No

DTC troubleshooting completed.