Caution / Notice / Hint

WARNING: This page is about a different car, the 2019 Toyota Highlander, 2018 Toyota Highlander, and 2017 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.

WARNING:

Before inspecting the high-voltage system or disconnecting a low voltage connector of the inverter with converter assembly, make sure to turn the power switch off. Also, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
Refer to PRECAUTION [11/2016 - ]

HINT:

Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

NOTE:

After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

Refer to PRECAUTION [11/2016 - ]

HINT:

After repair, clear the DTCs, turn the power switch off and wait for 30 seconds or more and perform the following procedure to confirm that the auxiliary battery low voltage indicated by this DTC has been repaired.
1. Wait for 2 minutes with the shift lever in P, the power switch on (READY) and the following conditions met, then confirm that Data List item "+B" is between 13.0 and 15.0 V.
  (If charging is not performed and the electrical load increases, +B voltage may not be steady and gradually drops.)
  1. Headlight switch is in the HI position.
  2. A/C blower fan switch is in the HI position.
  3. Window defogger switch is turned on.
By performing the following procedure, the DC/DC converter function can be checked.
1. Connect the AC/DC 400 A probe to the positive auxiliary battery cable.
  1. Turn the power switch on (READY) and leave the vehicle as it is until the electric current flowing to the auxiliary battery becomes 10 A or less.
  2. Turn the power switch on (READY) and the headlight switch and A/C blower fan switch in the HI position, and the window defogger turned on.
  3. Confirm that the current drawn from the auxiliary battery is 0 A or lower and the auxiliary battery voltage is between 13.0 and 15.0 V.

This DTC may be also stored when a part other than the DC/DC converter is malfunctioning or depending on user operation.

MALFUNCTION CASES TO STORE DTC P0A08-264

Malfunction Case	Remarks	Inspection Step
Fuse is blown (DC/DC-S)	-	2
A signal connector of the hybrid vehicle control ECU assembly or inverter is not connected securely.	-	3, 4
A fusible link is blown (DC/DC)	-	5
High-voltage insulation fault of the following (ground to body). - Between the motor and inverter - Between the generator and inverter - Between the rear motor and inverter	DTC P0A08-264 may be stored if the ground potential fluctuates due to a high-voltage insulation malfunction.	6, 19 to 21, 25 to 27
Check low-voltage line from the inverter to the hybrid vehicle control ECU assembly	Inspect the continuity and connection condition of the AMD and S lines.	7 to 10
NODD signal line	Check the NODD signal line from the inverter to the hybrid vehicle control ECU assembly. Check the NODD signal circuit inside the hybrid vehicle control ECU assembly.	11, 22
The DC/DC converter is malfunctioning	Inspect the DC/DC converter function.	12
DC/DC converter control is suspended due to overheating (inverter water pump with motor assembly is malfunctioning, the coolant is not sufficient, a hose is clogged, etc.)	When the inverter is overheating, the DC/DC converter has a self-protection function that may suspend the DC/DC converter control and output a DTC. The suspended DC/DC converter control will return to normal by clearing the DTCs and turning the power switch off.	13 to 16, 23
Check areas that caused the blown fuse (DC/DC-S)	-	17, 18, 24

If this vehicle is used to jump start another vehicle with a discharged battery, a fuse may blow due to overcurrent or the DC/DC converter self-protection may be activated. Also, if this vehicle is jump started by a vehicle with a 24 V battery, the same malfunction may occur and this DTC may be stored. (The suspended DC/DC converter control will return to normal by clearing the DTCs and turning the power switch off.)

Confirm that high electrical load equipment such as a high-capacitance audio device or electric kettle is used on the vehicle. (A fuse of the auxiliary battery may be blown due to overcurrent.)

If the DC/DC converter is malfunctioning, the auxiliary battery cannot be charged. Therefore, once the power switch is turned off, it may be impossible to turn it on (READY) again if the auxiliary battery is completely discharged. In this case, charge the auxiliary battery. Be careful as charging is not performed during the inspection.

If the power switch turns off immediately after it is turned on (READY), the auxiliary battery voltage may be low. Charge the auxiliary battery.