The P2400 code indicates that the engine control unit has detected an open or high‑resistance condition in the circuit that controls the evaporative emissions purge pump. This means the ECU believes the pump is not receiving power or is not operating correctly when it should be.
A broken, corroded, or disconnected wire or connector can prevent the pump from receiving the control signal.
The pump itself may be defective, with a broken internal relay or motor that stops it from turning on.
In rare cases the module may misinterpret the signal or have a fault in the circuit it drives.
A blown fuse or defective relay that supplies power to the purge pump circuit can mimic an open circuit.
Physical damage or corrosion along the harness can create an intermittent open condition.
The light indicates the ECU has detected that the purge pump circuit is not operating as expected, suggesting a possible open circuit, faulty pump, or related wiring issue.
Replacing the ECU is usually unnecessary and rarely the correct fix. The code typically points to a wiring or pump issue; diagnosing and repairing those components first is recommended.
Yes, the most common cause is a fault in the pump itself or its electrical connection. Wiring faults and fuse/relay issues are next most likely, with ECU problems being uncommon.