Technical Description of OBD-II Trouble Code
The circuit for controlling the bypass of the charge air cooler is experiencing high voltage.
What does that mean?
This generic powertrain diagnostic trouble code (DTC) is applicable to all OBD-II vehicles equipped with a charge air cooler, including vehicles from Ford, Chevy, Mazda, Toyota, and others.
In forced induction systems, a charge air cooler, also known as an intercooler (IC), is used to cool the air that the engine uses. This functions similarly to a radiator.
In the case of the intercooler, it cools the air to create a more efficient air/fuel mixture, resulting in better fuel mileage and performance. The intercooler is part of the charge pressure side of the induction system. The bypass valve allows the air to bypass the intercooler and be released into the atmosphere or recycled. The Engine Control Module (ECM) adjusts the valve based on current engine conditions and needs.
The ECM triggers the check engine light and displays the P022C code when it detects a condition outside of the specified range within the intercooler’s bypass control circuit and/or system. This code may be caused by a mechanical or electrical fault, with mechanical problems being more likely. However, both are possible.
The P022C code is set when the ECM detects an electrical value higher than desired.
What is the severity of this DTC?
In this case, the severity is moderate. It is important not to ignore this issue as it could quickly develop into a more serious problem. Remember, problems do not improve over time unless addressed. Engine damage can be expensive, so if you have exhausted your abilities, it is recommended to take your vehicle to a reputable repair facility.
What are some of the symptoms of the code?
Symptoms of the P022C engine code may include:
What are some of the common causes of the code?
Possible causes for this code include:
What are some troubleshooting steps for the P022C code?
It is recommended to check for any technical service bulletins (TSBs) related to your vehicle. Accessing a known fix can save time and money during the diagnosis process.
Tools
When working within the forced induction system, you may need the following tools:
Safety Tips
NOTE: ALWAYS verify and record the integrity of your battery and charging system before further troubleshooting.
Basic Step #1
Locate the charge air cooler bypass control valve by following the charge piping to the intercooler (IC). It may be directly mounted to the charge pipe. The location of the IC can vary depending on the make and model of your vehicle, but it may be mounted in the front bumper, front fenders, or directly under the hood. Once you find the valve, inspect it for any obvious physical damage.
NOTE: Make sure the engine is off.
Basic Step #2
If code P024B is active, it may be beneficial to remove the valve from the vehicle to verify its functionality. Once removed, check for any obstructions in the valve’s range of motion. If possible, clean the valve before reinstalling it.
NOTE: Always refer to the service manual first, as removing the valve may not be possible or recommended for your specific vehicle.
Basic Tip #3
Inspect the harness for the bypass valve, as it may be routed through areas exposed to the elements. Check closely for any nicks, cuts, signs of corrosion, etc. in the wires involved in the circuit.
NOTE: Disconnect the battery before performing any electrical repairs.
Basic Step #4
Depending on your scan tool, you may be able to verify the functionality of the valve by controlling it and observing its range of motion. If accessible, you could disconnect one end of the valve to gain visibility of the moving parts. Use your scan tool to fully open and close the valve while observing its mechanical operation. If you notice the valve sticking and there are no obstructions, it is likely that the valve is defective. In this case, you can try replacing it, but make sure the manufacturer recommends a new valve. Refer to the manual for guidance.
Basic Step #5
To rule out any electrical problems within the harness, you may need to disconnect it at the valve and the ECM. Use a multimeter to perform various basic electrical tests (e.g. continuity) to verify the integrity of the circuit. If everything checks out, there may be some input tests involving testing the connector at the valve to verify the ECM functionality with the valve.
