Toyota Prius Battery Codes P0A7F, P2011 and P0A80

Toyota Prius Battery Codes P0A7F, P2011 and P0A80

A second generation Toyota Prius is at least 12 years old and batteries may need to be replaced. Here's what the codes mean.

Battery pack replacement is becoming more common as hybrid vehicles age. The second-generation Prius started with the 2004 model year and lasted until 2009. They have racked up many miles in the past decade or more, and the nickel-metal hydride battery is probably not providing the same range as before.

Inside a second-generation Prius battery pack are 168 1.2-volt cells that produce 201.6 volts when fully charged. Twenty-eight battery modules are wired in series and configured into 14 blocks. The battery pack has a heat management system to optimize the temperature under hot and cold conditions. 

Any battery’s life comes down to the chemistry inside of it to store and discharge energy. Like all chemistry experiments, heat plays a part in the reaction inside the battery. Heat can degrade a battery and cause reduced capacity. Charge and discharge cycles can also take their toll on the battery. 

The Battery ECU measures the state of charge, internal resistance and current flow to determine the battery’s condition.

Identifying  Hybrid Battery Pack Deterioration

Most codes that indicate the battery needs replacement will turn on the check engine light, and a message will appear in the information center. 

These codes are what bring the customer to your shop.

Code P0A7F

Code P0A7F has the description of Hybrid Battery Pack Deterioration. The criteria for setting the code are based on profiles determined by Toyota engineers. The first is an increase in the internal resistance of the battery pack for one trip. The second criteria threshold is the state of charge of the battery. If the state of charge falls outside of the expected results for two trips, code P07AF is set. Also, the ECM will use the battery temperature sensor as part of the monitor’s enabling conditions. With this code, the only way to resolve it is to replace the battery pack.

Codes P3011-3024

The battery ECU can read the internal resistance and voltages of the battery blocks. All of the blocks should be within 0.3-volts of each other. If the values fall outside the parameters, a code will be set for a weak block. The monitor for these codes is continuous and sets immediately. Typically, the blocks in the center of the battery generate weak block codes. 

Code P0A80

The description for DTC P0A80 is Replace Hybrid Battery Pack. This code takes two trips to set and indicates the voltage difference in the blocks exceeds standards. The issue could be with the batteries or in the bus bar connections with the modules.

Replacement Options

There are remanufactured battery packs on the market. The remanufacturing process involves removing the modules from the battery pack and analyzing them. Bad cells are discarded, and the good cells from several batteries with similar performance are reused, so the battery is balanced. They will also install new bus bars and check the overall battery performance.

You May Also Like

Lexus Air Ride Repair

A conversion kit might cost less and provide better long-term results for the customer.

Lexus models, including the LS sedan, RX crossover and GX SUV, are some of the least problematic air ride vehicles on the road. In fact, most Lexus customers do not realize that their vehicle is equipped with an air suspension until something breaks.

What makes most Lexus systems unique is the lack of a reservoir. The compressor provides air “on-demand.” Most systems will use four ride height sensors that measure the height and speed of the wheel displacement. The suspension control ECM will filter the ride height readings and other sensor data from accelerometers, and even data from the engine ECU, to determine which air spring intakes air or exhausts it. The suspension control ECU will also adjust the valving of the dampeners for the best possible ride.

Toyota Direct Injection? Port Injection? Why Not Both?

Port fuel injection and direct fuel injection systems each have their advantages and disadvantages.

Toyota Squeaking Noise From Rear Suspension 

Follow the repair procedure in this bulletin to address this condition.

Toyota Milliwave Calibration Tips

Calibration is necessary due to several factors affecting the radar’s functionality.

Different Nameplates, Different Expectations

Honda is one of the least concerned manufacturers about system voltages when it comes to reflashing.

Other Posts

Key Programming

When it comes to key programming, there are different levels of security access depending on the year, make and model of the vehicle.

BMW 4-Series Service

The 4-series does not stray far from the typical BMW engineering and operation.

ECU Reflashing

Reflash procedures are not getting any faster.

LG Energy, Toyota Sign EV Battery Supply Agreement

LG Energy Solution to supply Toyota with 20GWh of high-nickel NCMA battery modules annually from 2025.