Fault code P023B is called “Charge Air Cooler Coolant Pump Control Circuit Low” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.
Technical description and explained code P023B
Diagnostic code P023B is a generic fault code, it is applicable to vehicles that have a turbocharger with an air cooler. Despite its general nature, the exact repair steps may differ depending on the make as well as the model.
A turbocharger is an air pump used to force air into the engine. It consists of two connected parts, a turbine and a compressor.
The turbine is attached to the exhaust manifold, where it is driven by the exhaust gases. The compressor is attached to the air intake. Both are connected by a shaft, so when the turbine spins, the compressor also spins, allowing the intake air to be drawn into the engine.
Many engines are equipped with a discharge air cooler, also known as an intercooler. Charge air coolers can be air-liquid or air-air, but they are all designed to cool the air entering the intake.
This error refers to an air-to-liquid type cooler, which uses a liquid and a pump to cool and pump it.
Code P023B is set when the PCM detects a low signal in the charge air coolant pump control circuit. The control lamp on the instrument panel will then illuminate, and the error will be written to the control module memory.
Symptoms of vehicle malfunctions
The main signal that an error P023B has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- Check engine control lamp on the control panel will light up (the code will be recorded in the memory as a malfunction).
- Poor operation and reduction of engine power.
- Increased fuel consumption.
- Abnormal engine temperature may occur.
- The emergency operation mode may be activated.
The error P023B is not considered very serious, as it does not affect the safety and drivability of the vehicle. But the car performance will be reduced, so it is recommended to eliminate the problem.
Factors that can cause this error code
The error code P023B can mean that one or more of the following problems have occurred:
- Internal mechanical obstruction in the discharge air coolant pump.
- Breakage in the coolant pump signal circuit.
- Corrosion or damage to the electrical connector.
- Short circuit in wiring harness to earth or voltage.
- Faulty charge air cooler.
- Sometimes faulty PCM is the cause.
How to fix or reset OBD-2 code P023B
Some suggested steps for troubleshooting and fix the error code P023B:
- Connect the OBD-II scanner to the vehicle’s diagnostic connector and read all stored data and error codes.
- Before continuing with the diagnosis of code P023B, clear any other errors that may be present.
- Check the electrical wiring relating to the charge air coolant pump circuit for shorts, open circuits, and damage.
- If necessary, repair or replace any wires that are shorted, broken, damaged, or corroded.
- Inspect the pump connector for looseness and corrosion.
- Check the discharge air cooler and repair or replace if necessary.
- If problem persists, check and reprogram or replace control module (PCM) if necessary.
Diagnose and repair of problems
You can begin diagnosing error P023B by visually inspecting the discharge air and related wiring. Look for loose connections and damaged wiring.
Also visually inspect the discharge air cooler and ducts. If damage is found, repair, then clear the code and see if it returns.
Testing the circuit
Using a diagnostic tool, monitor the data parameters from the discharge air cooler. Check the integrity of the charge air cooler control circuit.
The wiring harness as well as the control circuit can be checked with a multimeter. The check should be done by disconnecting the connector at the PCM and the other end at the coolant coolant pump.
Check the coolant coolant pump
Disconnect the connector from the charge air coolant pump. Then measure the resistance between the two leads with a digital multimeter set to ohms.
To check the operation of the pump, connect the ground and also apply 12V to the pump, once connected it should start. If it does not start, then the pump is defective and must be replaced.
After fixing the found faults, the problem with the error P023B should be solved.
On which vehicles does this problem occur most frequently
Fault code P023B can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- Chevrolet
- Citroen (C4)
- Dodge
- Ford
- Jaguar
- Mazda
- Peugeot (3008, 308)
- Toyota
- Volkswagen (Golf)
Fault code P023B can sometimes be found with other errors. The most common are the following: P023A, P023C, P0598, P0947.
