P0A80 Replace Hybrid Battery Pack

Description and meaning of DTC p0a80

This generic powertrain diagnostic trouble code (DTC) typically applies to many OBD-II hybrid electric vehicles. That may include but is not limited to vehicles from Toyota (Prius, Camry), Lexus, Fisker, Ford, Hyundai, GM, etc. When a code P0A80 is stored, it means that the powertrain control module has detected a malfunction in the hybrid vehicle battery management system (HVBMS). This code indicates that a weak cell failure has occurred in the hybrid battery pack. Hybrid vehicles (which do not require external charging) utilize nickel metal-hydride battery packs. Battery packs are actually blocks of batteries (modules) that are wired together using sections of busbar connectors or cables. The typical HV battery is composed of eight (1. 2-volt) cells in series. Twenty-eight modules make up the typical HV battery pack. The HVBMS regulates the charging level of the battery pack and monitors its state. Individual cell resistance, battery voltage, and battery temperature are all factors that are considered by the HVBMS and PCM when determining battery pack condition and the desired charging level. Multiple ammeter sensors and temperature sensors are placed at strategic points throughout the HV battery pack. In most cases, each cell is equipped with a ammeter/temperature sensor. These sensors provide the HVBMS with data from each cell. The HVBMS compares individual voltage signals to determine if inconsistencies are present and reacts accordingly. The HVBMS also provides the PCM with data, via the controller area network (CAN), regarding battery charge level and battery pack condition. When the HVBMS provides the PCM with an input signal which reflects inconsistent battery or cell temperature and/or voltage (resistance), a code P0A80 will be stored and a malfunction indicator lamp may be illuminated.

p0a80 diagnostic trouble code symptoms

Symptoms of a P0A80 trouble code may include:Decreased fuel efficiencyDiminished overall performanceOther HV battery related codesElectric propulsion system deactivation

DTC p0a80 - possible causes

Causes for this code may include:Defective HV battery, cell, or battery packHVBMS sensor failureIndividual cell resistance is excessiveDiscrepancies in cell voltage or temperatureHV battery pack fans not working properlyLoose, broken, or corroded busbar connectors or cables

How to fix OBD-II diagnostic trouble code p0a80

NOTE: The high voltage battery pack should only be serviced by qualified personnel. If the HV in question has more than 100,000-miles on the odometer, suspect HV battery pack failure. If the vehicle has less than 100K miles, a loose or corroded connection is probably the source of your malfunction. HV battery pack repair or remanufacture is a possibility but either of these options may prove unreliable. The safest method to rectify a defective HV battery pack is replacement with a factory part. If this is cost prohibitive for the situation, consider a used HV battery pack. A diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of HV battery diagnostic information will be needed to diagnose a code P0A80. Use the scanner to observe HV battery charging data after obtaining testing procedures and specifications from the HV information source. Component location diagrams, wiring diagrams, connector face views, and connector pin out charts will be instrumental in reaching an accurate diagnosis. Visually inspect the HV battery pack and all circuitry for signs of corrosion or open circuits. Remove corrosion and repair defective components as required. After retrieving all stored codes and pertinent freeze frame data (connect the scanner to the vehicle diagnostic port), clear the codes and test drive the vehicle to see if the P0A80 is reset. Test drive the vehicle until the PCM either enters readiness mode or the code is reset. If the code is reset, use the scanner to identify the HV battery cells which are experiencing inconsistencies. Make a note of the cells and continue with your diagnosis. Using freeze frame data (from the scanner), determine whether the condition which caused the P0A80 to be stored involved an open circuit, high cell/circuit resistance, or an HV battery pack temperature discrepancy. Test appropriate HVBMS sensors (temperature and voltage) by following manufacturer testing specifications and procedures. Replace sensors which do not comply with manufacturer’s specs. You may test individual cells for resistance using the DVOM. If the individual cells exhibit an acceptable degree of resistance, use the DVOM to test resistance in busbar connectors and cables. Individual cells and batteries may be replaced but total HV battery pack replacement may prove to be the most reliable fix. A stored code P0A80 will not automatically deactivate the HV battery charging system but the conditions which caused the code to be stored may disable it

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