P0204 Injector Circuit Malfunction Cylinder 4

OBD2 Code: P0204

Description: Injector Circuit Malfunction – Cylinder 4

Definition: This code indicates that the engine control module (ECM) has detected a malfunction in the injector circuit for cylinder number 4. The issue could be due to an electrical problem, such as a short or open circuit, or a faulty fuel injector.

P0202 Injector Circuit Malfunction Cylinder 2

OBD2 Code: P0202

Description: Injector Circuit Malfunction – Cylinder 2

Definition: This code signifies that there is an issue with the injector circuit for cylinder number 2. Similar to P0204, it can be caused by wiring problems, connector issues, or a defective fuel injector itself.

p0204 – Injector Circuit Malfunction Cylinder 4

Typical Severity: Moderate

Common Causes

P0204 – Injector Circuit Malfunction Cylinder 4

Common Causes:

• Faulty fuel injector in cylinder 4
• Open or short circuit in the wiring harness connected to injector 4
• Poor electrical connection at the injector or ECM
• ECM (Engine Control Module) issue

 

Common Misdiagnosis

OBD2 Code: P0204

Description: Injector Circuit Malfunction Cylinder 4

Common Misdiagnosis: Replacing the fuel injector without checking for wiring issues or ECM faults.

OBD2 Code: P0202

Description: Injector Circuit Malfunction Cylinder 2

Common Misdiagnosis: Assuming the injector is faulty when the problem may be due to a poor electrical connection or a fault in the PCM.

 

Common Diagnostic Steps

OBD2 Code: P0204

Description: Injector Circuit Malfunction Cylinder 4

• Check the injector wiring and connectors for damage or corrosion.
• Test the fuel injector using a multimeter to ensure it is within the specified resistance range.
• Inspect the ECM/PCM for any signs of damage or malfunction.
• Verify that there is proper voltage supply to the injector circuit.
• Perform a continuity test on the injector circuit wires.
• Swap the injector with another cylinder to see if the problem follows, indicating a faulty injector.

OBD2 Code: P0202

Description: Injector Circuit Malfunction Cylinder 2

• Inspect and clean all electrical connections related to cylinder 2’s fuel injector.
• Use an ohmmeter to check for correct resistance in the fuel injector coil.
• Examine wiring harnesses for shorts, opens, or other issues affecting connectivity.
• Ensure that power and ground signals are reaching the fuel injector properly.
• If available, use an oscilloscope to observe pulse width modulation signals from ECM/PCM to the injector.
• If necessary, replace or repair damaged components such as wires, connectors, or injectors themselves.