Guide To P0AA4 OBD Error Code Solutions

<<See All OBD Codes

The trouble code P0AA4 can be explicated as Hybrid Battery Negative Contactor Circuit Stuck Closed. This trouble code is generic, which would mean that it can apply to all the vehicles which are equipped with the OBD-II or the vehicles which are made since 1996 up to the present. The specifications on the definition, the troubleshooting steps as well as repairs can always vary from one vehicle to another. This can happen because of a lot of reasons and the mechanic should diagnose the specific cause for this code.

It is the hybrid control module which would examine the hybrid battery negative contactor circuit. This trouble code would be set by the hybrid control module when it won’t be able to control the control circuit to the high voltage battery, as per the parameters set by the manufacturer.

What causes this problem with the Hybrid Battery Negative Contactor Circuit Stuck Closed?

• Imperfect system main relay
• Issue of unbolted system main relay harness
• Unacceptable electrical connection in the system main relay circuit=
• There can be distorted HV control ECU

1. Hybrid Drive Cooling Pump - Check for faults in the hybrid battery cooling pump and replace it, if required. If the cooling pump does not function properly, then the battery might not work to its full capacity and can cause serious performance issues.
2. Battery Temperature Sensor - Inspect for faulty battery temperature sensor as it may cause the battery to overheat and not work properly and cause serious physical damages to various starting and charging system components. Thus, replace faulty sensor now!
3. Hybrid Battery - The battery itself can be faulty and can be overheating, which can lead to faster discharge and slower charging, with risks of leakages and other damages to the vehicle. Thus, immediate replacement is advisable.
4. Engine Control Module - Want to know the most common reason behind the failure in the engine control module? Corrosion or damage because of moisture can cause ECM failure. Corrosion might enter the ECM through the wiring harness and moisture can enter by a failure in the seals in the ECM itself.
5. Car Battery - Faulty car battery can have the problem of overheating and fast discharging. Thus, it can affect the motor performance as well as damaged major components. Replace it immediately.
6. Powertrain Control Module - The PCM makes the engine and transmission work in tandem. Any issue with the powertrain control module will cause major problems with the efficient running of the vehicle.
7. Electronic Control Unit - If your vehicle fails to start for no apparent reason, this is also a good indicator that there can be some issues with the ECU. If you check the car battery, starter and other common electrical components, and the vehicle still does not start, a quirky electronic control unit should be the next logical thing to consider.
8. Inverter Cooler Pump - The inverter cooler pump can also be faulty and not respond to the PCM instructions. This means that even though the temperature sensor and the PCM are working properly, the cooler pump may not work and cause damage to the battery functions. Thus, replace it immediately.

It is essential to know the symptoms of an issue as only then you would be able to solve the problem. So that’s why we have listed out some major symptoms of OBD Code P0AA4 here:

Common Symptoms

• Illumination in the service engine soon light

If you wish to correct this fault code, then you have to follow certain steps. Correcting a problem needs your careful attention. Here are some ways with the help of which you will be able to correct the OBD Code P0AA4:

• The malfunctioning PCM should be repaired or replaced as per the need
• Carefully adjust the faults in the system main relay harness
• The HV control ECU should be restored to working order
• Recondition the non-functioning system main relay circuit
• Adjust the flawed system main relay

Parts Avatar Canada is here to solve all your issues related to car parts. We have stocked a wide range of best priced ecu, battery relay, hv control ecu, battery relay harness, battery relay switch, hv battery, pcm car, ecm car and engine control module and a lot more to help you out in fixing your car.

If you want to easily diagnose this trouble code, then you must follow the steps which are mentioned here as below:

Firstly, if in case, you encounter white smoke, it means that the fuel that has been injected into the combustion chamber has not been burned as per the needs. The causes that generate white smoke include simple issues like low engine compression or water in the fuel to the fuel pump timing being thrown off due to something that is keeping the fuel away from getting to the pump as per the requirements. It is important that parts should not only be repaired or replaced with reference to the OBD-II error code P0AA4. Also, consult the vehicle service manual for more information on possible causes of the code along with the testing required.

Common Mistakes When Diagnosing The P0AA4 Code

• Quirks in the high voltage control module
• Issues related with the car wiring