Error Code P0C81: What It Means & What To Do?

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What does P0C81 error code signify? What are its symptoms? Are these questions popping in your mind? Then you are at the right place for a solution. The issues with the wires are generally referred to as hybrid battery temperature sensor ‘H’ circuit. The monitoring of the temperature of each battery cell is usually carried out by the hybrid battery pack by utilizing multiple sensors. If an unlikely temperature is found in the report of at least one of the battery temperature sensor, then the error code P0C81 will be set. Failure of multiple sensors will likely deactivate the high voltage system.

The HV battery is provided with a battery temperature sensor in 3 of its locations. The thermistor’s resistance, which is inbuilt in each of the battery temperature sensors, differs according to the changes in the HV battery temperature. High thermistor resistance means low battery temperature. On the other hand, if the temperature is high, then the resistance will be low. Just to find the HV battery temperature, the battery temperature sensors are used by the battery smart unit which then sends the observed value to the power management control ECU. The blower fan will then be controlled by the power management control ECU depending on the outcome of this detection.

What causes this problem with the Hybrid Battery Temperature Sensor "H" Circuit?

• The hybrid battery thermistor might be damaged.
• You will see an opening or short-circuit in the hybrid battery thermistor harness.
• Bad electrical connection in the hybrid battery thermistor circuit.
• Malfunctioning battery smart unit.

1. Hybrid Battery Temperature Sensor - Does the engine surge during operation? Is the battery voltage low? Is the battery light illuminated? These are the symptoms of a faulty hybrid battery temperature sensor. Replace it as soon as possible.
2. Hybrid Battery Pack - The hybrid battery packs are usually covered with lithium phosphate and they are designed to be smaller and lighter in weight than usual batteries. Any damage to this hybrid battery pack will need an immediate replacement.
3. Engine Wiring Connectors - The terminals of the engine wiring connectors must be connected properly. Else it might get damaged easily. Get the engine wiring connectors for your vehicle from PartsAvatar.
4. Battery Temperature Sensors - The battery temperature sensor will be faulty if the voltage is too high or if the sensor itself is damaged. In one such situation, it is always best to replace the defective battery temperature sensor so avoid further complications.
5. Battery Assembly - Does the engine fail to start? Does the engine light keep flashing? Then it is an indication that the battery assembly is malfunctioning which needs replacement.
6. Battery Control Module - Battery control module provides an extended battery life and helps to increase the fuel economy. If you find the battery control module to be defective replace it with the right component by shopping them from PartsAvatar.
7. Battery Smart Unit - The illumination of the malfunction indicator lamp will occur if the battery smart unit is found to be defective. Avoid the P0C81 error code by replacing the defective battery smart unit.
8. Diesel Particulate Filter - A common symptom for a defective DPF is the EGR valves which have blockages. Clear the blockages or replace the defective DPF with a new one by shopping it from PartsAvatar.
9. Engine Control Unit - If the ECU is damaged, it can cause sudden jerking or stopping of the vehicle. It’s best to replace the damaged ECU with a new one to avoid further malfunctioning of the vehicle.
10. Carburetor - Do you see any black smoke from the exhaust? It means your carburetor is damaged which needs immediate replacement.
11. Spark Plugs - The engine will keep surging or it will hesitate to start if the spark plugs are faulty. Replace them immediately to avoid the P0C81 error code getting stored.
12. Distributor Cap - A defective distributor cap will prevent your spark plugs from firing. Replace the damaged distributor cap immediately.
13. Engine Gasket - There will be leakage of oil if the engine gasket is faulty. Change the damaged engine gasket as soon as possible.
14. VCT Solenoid - Is the engine oil dirty? Do you find the fuel economy to be less? Then it’s high time that you replace the defective VCT solenoid so that the P0C81 error code does not get stored in your vehicle

Interested in knowing the symptoms to OBD code P0C81? If yes, then you have arrived at the right place. We at PartsAvatar have listed out few common symptoms associated with this fuel injector problem.

Common Symptoms

• The light will stay the same or it will light occasionally when the DPF is restored.
• During acceleration, the engine might be slow.
• If the DPF is not corrected, then until the situation is made alright, the ECU will stay in the ‘limp home mode’.

We have listed out some ways which would help you to correct the occurrence of OBD Code P0C81. They are mentioned here as follows:

• Replacing the faulty battery smart unit.
• Changing the engine wiring connectors that is damaged.
• The faulty hybrid battery thermistor must be changed.
• The malfunctioning circuit or the harness of the hybrid battery thermistor must be fixed.

There is no need to be anxious as Parts Avatar – Car Parts Online is here to help you out! We have high-grade, hybrid battery thermistor, electrical connector, battery temperature sensors, battery assembly, DPF, ECU, carburetor, spark plugs, distributor cap, engine gasket and a lot more for our precious customers.

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P0C81 code to be stored:

• If this error code is stored, as you accelerate the vehicle you will hear a very loud noise similar to an explosion from the back of your vehicle.
• Make sure that both the fuel and air combination are correctly balanced by checking the carburetor.
• If each of these settings is perfect, then you have to carefully check the distributor cap for any possible cracks or hairline splits as it can likely cause a backfire.
• Now check the spark plugs to make sure that they are clean and not defective.
• Inspect the engine gaskets for any possible signs of damage because they are responsible to make sure that the gas exchange within the engine is correct.
• The error code – P0C81 is generally related to camshaft timing.
• The illumination of engine light will take place if the cam-timing is over-retarded and the error code will be set in the vehicle.

Common Mistakes When Diagnosing The P0C81 Code

The technician may go about searching for the issue in the wrong car part while diagnosing the P0C81 error, whereas the issue may be with the high voltage battery control module, electrical wires and the high voltage battery assembly which appears to be faulty.