Toyota Aqua HV and Check Engine Light Code

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Toyota Aqua HV and Check Engine Light Code

Salam everyone! I hope youre all doing well.

I’m having a problem with my Toyota Aqua. While driving on the highway, several warning lights appeared on the meter, including the check engine light, slip warning light, EBD light, and Hybrid System Abnormal light. I pulled over to the side and had a local electrician check it out. He plugged in his OBD scanner and found one code: P0A80 – Replace Hybrid Battery Pack.

Given that the car has just over 100,000 km, I decided to clear the codes. After doing so, no codes reappeared for the rest of the day. However, the next day, while driving on the highway again, the same warning lights came back on. I took the car to the electrician again, and he cleared the codes at my request, but mentioned that the only solution would be to replace the hybrid battery.

Not convinced, I went to another electrician who suggested that a motor cleaning located somewhere under the back seat might help. After doing some research, I found that in rare cases, a malfunctioning cooling fan could cause this code due to overheating of the battery. I inspected the fan, and it was clean.

If anyone has any advice o r insights on what could be causing this issue, I’d greatly appreciate it!

Model: Toyota Aqua 2015 S Package Key Start
Mileage: 112,950 km.

Lubaba asked on 24 Jan 2025 12:26:06 pm

1 Answer

22 views |

Car Mechanic Expert - on 24 Jan 2025 12:27:49 pm

In many cases, the terminals of the battery pack cells become corroded, which restricts proper current flow and triggers a warning to replace the battery pack. These batteries are equipped with a kill switch, which, when removed, makes it completely safe to work on them.

You can easily remove the battery pack, open it up, and clean all the terminals by soaking them in vinegar. If the cells themselves are not weak, cleaning the terminals can extend the battery’s life by another 20,000 km o r more. This is a task you can handle at home, as mechanics often charge so much for this service that you might regret not simply replacing the battery.

There are plenty of tutorials on YouTube for the Prius and Prius C the Aqua is known as the Prius C in the United States that can guide you through the process. Give it a try and enjoy the savings!