Software Update [10/2023 - ]: Procedure

PREPARATION WORK

NOTE:

If the voltage drops or fluctuates as an individual system or electric fan is activated during wired reprogramming, it becomes impossible to write the software, potentially damaging the ECU.

Electrical load reduction
1. Turn off all the systems that can be stopped and have an electrical load.
  HINT:
  - Exterior lights
  - Interior lights (turn off so that they do not come on even if a door is opened)
  - Air conditioning system
  - Audio/navigation system
  - Seat belt warning (belt lock)
  - Retrofitted equipment, etc.
  - Other commercially available electrical components (remote starter, security, etc.)
2. Remove the electric fan fuse or relay.
Battery voltage inspection
1. Turn the engine switch to ON (IG) and wait for 1 minute.
  Standard Voltage
  
  11.8 V or higher
2. If the battery voltage is below 11.8 V, recharge or replace the battery.

Connection of a battery charger and charging battery to the battery (assistance terminal)

NOTE:

If the No. 2 skid control ECU (brake actuator assembly) of the HV model is activated, a large current flows and wired reprogramming becomes unavailable because the drop in voltage cannot be compensated for by the battery charger alone. Therefore, in the case of the HV model, connect not only a battery charger but also an charging battery in parallel when performing wired reprogramming.

Check of the deterioration status of the charging battery
1. Perform an inspection using a conductance-type battery tester or a load-type battery tester (which discharges 100 A for 5 seconds or more).
  HINT:
  
  If any of the above battery testers is not available, remove the battery of another vehicle (whose displacement is 2 liter (2.1 US qts, 1.8 Imp. qts) or less) and check that the engine can be started, with the charging battery mounted. If the engine cannot be started, replace the charging battery.
  
  (This is to check that there is no short circuit in the charging battery.)
2. If the inspection result of the charging battery is not OK, replace the charging battery.
Check of the charging status of the charging battery
1. Inspect the open circuit voltage of the charging battery (when not connected).
  Standard Voltage
  
  12.6 V or higher
2. If the voltage of the charging battery is below 12.6 V, recharge or replace the charging battery.

Installation of the battery terminal attachment set

NOTE:

When not in use, remove the battery terminal attachment set from the charging battery and store it. Keeping the battery terminal attachment set attached can cause a short circuit.

Check the bar part of the battery terminal attachment set for looseness.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Battery terminal attachment set
*b	Check for looseness

Install the battery terminal attachment set to the charging battery.

To prevent the wrong connection, put positive (+) and negative (-) labels or other markings on the charging battery.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Auxiliary charging battery
*b	Positive (+) and negative (-) labels for wrong connection prevention
*c	Battery terminal attachment set

Connection of a battery charger, charging battery and booster cable

NOTE:

When using a battery charger that requires manual current value setting, be careful not to cause overcharging.
If the battery charger is connected to the vehicle when the power of the battery charger is on, the fuse may blow out. When connecting the battery charger to the vehicle, make sure that its power is off.
When the vehicle has an assistance terminal, connect the positive end of the booster cable to the assistance terminal, not the positive terminal of the battery.

Turn off the battery charger.
Connect the battery charger and charging battery.
NOTE:
To prevent the wrong connection, connect them according to the positive (+) and negative (-) labels put on the charging battery.
Connect the booster cable to the charging battery.

Connect the positive end of the booster cable to the positive terminal (assistance terminal) of the battery and the negative end to a metallic part of the uncoated vehicle.

NOTE:

Connect the battery charger, charging battery, booster cable and vehicle in parallel.

*a	The illustration shown is an example only.

COMPONENTS TO BE REPLACED

Operate the Techstream to perform Health Check.
Check the DTC and perform diagnosis by following the instructions given in "How to Proceed with Troubleshooting".

If the component needs to be replaced as a result of the diagnosis, perform the following procedure.

Target component	Reference
Forward recognition camera	3. COMPONENT REPLACEMENT AND WIRED REPROGRAMMING

COMPONENT REPLACEMENT AND WIRED REPROGRAMMING

Replace the component with a new one.
NOTE:
When replacing the component, always replace it with a new one. If a product installed to another vehicle is used, the information stored in the ECU does not match the information from the vehicle and a DTC may be stored.

HINT:

For information about component replacement, refer to the removal/installation procedure of the relevant component.
Using the Techstream, check if a software update is necessary, and perform a wired software update as necessary.
1. Refer to Service Bulletin for information about ECU program rewriting.
When the forward recognition camera has been replaced with a new one, it is necessary to perform optical axis alignment for the forward recognition camera.
HINT:

Forward recognition camera beam axis alignment can be performed by using "One Time Recognition", "Driving Adjustment" or "Camera Axis Adjustment Value Write".

One Time Recognition: Refer to TARGET ADJUSTMENT(ONE TIME RECOGNITION) [10/2023 - ]

Driving Adjustment: Refer to DRIVING ADJUSTMENT [10/2023 - ]

Camera Axis Adjustment Value Write: Refer to CAMERA AXIS ADJUSTMENT VALUE WRITE [10/2023 - ]
Perform Update ECU Security Key.
Refer to UPDATE ECU SECURITY KEY [10/2023 - ]
Clear the Vehicle Control History (RoB).
Refer to VEHICLE CONTROL HISTORY (RoB) [10/2023 - ]

Turn the engine switch to ON (IG), wait for 5 minutes, then confirm that the following notification is not displayed on the multi-information display.

Multi-information display
System Malfunction Visit Your Dealer