P0202 indicates a problem with the electrical circuit for the fuel injector on cylinder 2. The powertrain control module (PCM) has detected an abnormal voltage condition, such as an open or short, in that injector's driver circuit.
The injector may have a shorted coil or internal failure that prevents it from opening and closing correctly.
Corrosion, broken wires, or a loose connector can cause an open or intermittent circuit to the injector.
A malfunction in the PCM's output driver for cylinder 2 can produce abnormal voltage readings.
A blown or partially failed fuse supplying injector power can cause the circuit to read low voltage.
A bad engine ground strap or low battery voltage can affect injector circuit performance.
Yes, but it is relatively uncommon. The PCM’s injector driver can fail, but most P0202 codes are due to the injector, its wiring, or the connector.
Replace or repair the injector only after confirming it is the faulty component through resistance testing or a functional swap. Premature replacement can lead to unnecessary expense.
That recommendation is often based on a misinterpretation of the code. In the majority of cases, the issue is with the injector or its wiring, not the PCM. Replacing the PCM should be a last resort after all other diagnostics have been exhausted.
A malfunctioning cylinder 2 injector can create a misfire that the engine control system may try to compensate for, leading to rough idle, loss of power, and sometimes symptoms that appear to involve other cylinders.