Fault code P0A80 is called “Replace Hybrid Battery Pack” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.
Technical description and explained code P0A80
The P0A80 fault code is intended to be displayed exclusively on hybrid vehicles. Indicates that the Powertrain Control Module (PCM) has detected a fault in the Hybrid Vehicle Battery Management System (HVBMS). Which indicates that an individual cell failure has occurred in the hybrid battery pack.
Hybrid cars mainly use nickel-metal hydride battery packs. The battery packs are modules connected together by connectors or cables.
A typical hybrid car battery consists of eight (1.2 volt) cells connected in series. A hybrid car battery pack consists of 28 modules.
The HVBMS regulates the charge level of the battery and monitors its condition based on resistance, voltage and temperature. All of these factors are taken into account by the control module (PCM) in determining the condition of the battery pack and the required charging level.
In most cases, each cell is equipped with an ammeter and temperature sensor. These sensors provide the HVBMS with data from each cell.
The HVBMS compares the individual voltage signals to determine if there are discrepancies. Also, data about the battery charge level and the status of the battery pack come to the PCM via the Controller Area Network (CAN).
If the HVBMS sends an input signal to the PCM that reflects a voltage or resistance mismatch in the battery or cell temperature. Then code P0A80 will be stored and the malfunction indicator light may illuminate.
Symptoms of vehicle malfunctions
The main signal that an error P0A80 has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- The “Check engine” control lamp on the control panel will illuminate (the code will be stored as a fault).
- Other high voltage battery related codes may be present.
- Reduced vehicle performance.
- Increased fuel consumption.
- Deactivation of the electric motor unit.
The severity of fault code P0A80 is high, as the fault is related to a major component of the vehicle’s hybrid drive. The problem should be corrected as soon as possible.
Factors that can cause this error code
The error code P0A80 can mean that one or more of the following problems have occurred:
- Faulty high voltage battery cell or battery pack.
- High resistance of individual cells.
- Inconsistencies in battery cell voltage or temperature.
- Corrosion, loose or broken electrical wiring and connections.
- Hybrid car’s battery pack fans are not working properly.
- HVBMS sensor malfunction.
How to fix or reset OBD-2 code P0A80
Some suggested steps for troubleshooting and fix the error code P0A80:
- Connect an OBD-II scanner to the vehicle’s diagnostic connector and read all stored data and error codes.
- Clear the error codes from the computer memory and test-drive the vehicle to see if the P0A80 code appears again.
- If the error code appears again, visually inspect the electrical wires and connectors.
- If necessary, repair or replace any shorted, broken, damaged, or corroded components.
- Test the high voltage battery fan.
- Check the operation of the high voltage battery temperature sensor.
- Check the fan control relay and replace it if necessary.
- Test the high voltage battery pack.
- If the problem persists, check and replace the power control module (PCM) if necessary.
Diagnose and repair of problems
The first step in the P0A80 troubleshooting process is to review the Technical Service Bulletins (TSB). For known problems with a particular vehicle.
The advanced diagnostic steps are very vehicle specific. They may require, special equipment and knowledge to accurately perform the steps.
Visual inspection
Visually inspect the hybrid vehicle battery pack and all electrical circuits for signs of corrosion or open circuits. If necessary, remove corrosion and repair defective components.
After retrieving all stored codes, remove them and perform a test drive on the vehicle to verify that code P0A80 has been reset. Use the scan tool to identify the battery cells that are mismatched.
Use a multimeter to check the battery cells for resistance that are out of compliance. You can try replacing individual failed battery cells, but the most reliable solution is to replace the entire battery pack.
Test the HVBMS temperature and voltage sensors by following the manufacturer’s specifications and testing procedures. Replace the sensors if they do not meet the manufacturer’s specifications.
The stored code P0A80 itself does not automatically disable the HVBMS battery charging system, but the conditions that caused the stored error may disable it.
If these actions did not help to find the failure, there may be a bad connection to the PCM or the PCM itself is defective. If this is the case, it is best to consult a specialist for reprogramming or replacing the control unit.
On which vehicles does this problem occur most frequently
Fault code P0A80 can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- Dodge
- Ford
- Hyundai
- Lexus (400h, GS450h, LS600h, RX400h, RX450h)
- Nissan (Altima)
- Toyota (Aqua, Auris, Camry, Estima, Prius)
Fault code P0A80 can sometimes be found with other errors. The most common are the following: P0517, P0A7D, P0A7E, P0A7F, P0A81, P0A82, P0A83, P0A84, P0A85, P3025.
