Error Code P053B is defined as Positive Crankcase Ventilation Heater Control Circuit Low. Error Code P053B is a generic trouble code, meaning it applies to all vehicles equipped with OBD-II system, specifically those made since 1996 up to present. It commonly appears among BMW, Chrysler, Ford, Jeep, Mini, etc. Specifications on the definition, troubleshooting, and repairs, of course, can vary from one make and model to another.
To remove harmful emissions from the engine, engineers provide the engine system with a PCV (positive crankcase ventilation), a system designed to keep these said vapors from getting to the atmosphere. The vehicle is also able to do so using manifold vacuum, as the latter sucks vapors from the crankcase in the intake manifold. The crankcase vapors are lead through the combustion chambers, along with fuel and air mixture, to be burned. To control the circulation within this system, a PCV valve is provided – this is both the ventilation system for the crankcase and its pollution management device.
Since the 1960s, PCV has become a standard for vehicles, and are two basic types of PCV systems, which the open and closed systems. Both works similarly, however, since the closed system has been proven to be more effective (since 1968), it has become the more commonly used pollution control system.
With the help of heater system/element, PCV can remove moisture, which happens to play the biggest role in collecting contaminants within the engine. As the engine runs, it generates heat that will burn off most of the moisture in the system. When the engine cools down, however, condensation automatically starts. This is why oils are added with specific additives, which works by suspending the water molecule caused by moisture. In due time, however, this can exceed its capacity, as the water continues to corrode the metal parts of the engine that damages it to an extent.
The PCM (powertrain control module, also known as ECM or engine control module in other vehicle makes) controls and adjusts the PCV heater control circuit. Error Code P053B is set when the PCM detects that the electrical condition within the PCV heater control circuit is experiencing low voltage than specified.
As with other error codes, this code activates the Check Engine light and registers the code to the vehicle’s memory system. Other common symptoms include:
- Engine misfire
- Sludge in oil
- Engine oil leak
- Excessive oil consumption
- Increase in fuel consumption
- Failed PCV valve can also lead to noise such as a whistle, whine, or other moaning noise
- Stuck open PCV valve
- Open or short in the wiring of PCV heater control circuit
- Out of range condition in PCV heater control circuit
- Oil contamination of electrical connector and harnesses, causing electrical connection issues
- Contaminated inline PCV air filter (possibly internal)
- Defective PCV heater
How to Check
As with most malfunctions codes, a TSB (Technical Service Bulletins) can help in troubleshooting P053A. Advanced diagnostic steps can be vehicle specific, and may require the right set of tools or skills to perform accurately. For this guide, we have included the basic steps that you can follow. However, it is best to refer to your TSB and look for the vehicle’s year, make, model, and powertrain for the specific diagnosis and repair guide.
There are many ways to check the PCV valve, so you will have to decide which step is more convenient for you. Whatever the method you choose, make sure the engine is idling. Here are the two methods to diagnose the PCV.
With all the hose intact, disconnect the PCV valve from the valve cover. Then, carefully place your finger over the open end of the hose. If the valve is working properly, you will feel a strong suction. After this, shake the valve. If it rattles, that means there isn’t anything that obstructs the pathway. If it doesn’t rattle, however, it means it’s damaged.
Take off the cap from the oil filler hole on the valve corner, then place a stiff piece of paper on top of the opening. The paper must be sucked in place against the hole in a matter of seconds if the valve is working properly.
However, if you find out that the valve is not working properly, it is important that you don’t jump into replacing it. Rather, try cleaning the valve using a carburetor cleaner, sparingly, especially in areas with great contamination. Verify any present discoloration and remove any gummy deposits, as this can be a good indicator that the valve is cleaned.
Check the harness involved in the circuits of the PCV system. The PCV system is subjected to oil, which is why oil contamination can be a common cause of the problem.
For oil leaks on harness, connectors, and wires, oil leak can lead to electrical issues, as oil can cause wear to the wire insulation. If you see anything of this nature, make sure to do the necessary repair or replacement of the problematic connection within the PCV heater control circuit
Verify the harness involved in the PCV system’s circuit(s). Given the fact that the PCV systems are subject to oil present within the system, one of the possible causes is oil contamination. If oil is leaking on harnesses, wires, and connectors, this could cause electrical issues, because the oil can and will, over time, eat away at the important wire insulation. So, if you see anything of this nature, make sure to repair it adequately to ensure a good electrical connection within the positive crankcase ventilation heater control circuit.
How to Fix
Depending on the diagnosis, common repairs for this code include:
- Replacement of the PCV valve
- Thoroughly cleaning of the PCV valve using carburetor cleaner
- Repair of oil leaks in the PCV heater control circuit
- Repair or replacement of damaged connector, wire, and harness in PCV heater control circuit caused by oil contamination
As said earlier, this guide is for general information purposes only. It is best to refer to your TSB for the specific steps for both diagnosis and repair of this error code.