OBD-II Generic Error Code P2402: How to Fix It

Q: Can I drive my car with a P2402 code?

Yes, in most cases your vehicle will continue to drive normally with a P2402 code active. However, you will have a check engine light on, which means you will fail an emissions inspection. You should address the issue within a reasonable timeframe since EVAP faults can worsen and, in rare cases, indicate fuel vapor leaks that pose a fire or health risk.

Q: What causes the P2402 code to appear?

The most common causes of P2402 include a failed EVAP leak detection pump, a short to voltage in the pump control wiring harness, a corroded or damaged electrical connector at the pump, a blown fuse in the EVAP circuit, or — less commonly — a faulty ECM output driver. Rodent damage to wiring is also a surprisingly frequent cause on vehicles stored outdoors.

Q: How much does it cost to fix a P2402 code at a shop?

Repair costs vary widely depending on the vehicle and the root cause. If only the EVAP leak detection pump needs replacement, expect to pay between $150 and $400 including parts and labor. If the issue is wiring harness repair, costs can range from $100 to $300 depending on the extent of damage. ECM replacement or reprogramming is the most expensive option, often $500 to $1,200 or more.

Q: Will a P2402 code clear itself if the problem goes away?

If the fault is intermittent and does not occur during subsequent drive cycles, most vehicles will automatically clear the check engine light after a set number of successful drive cycles (typically 40 or more warm-up cycles without the fault reappearing). However, it is best practice to diagnose and repair the root cause rather than waiting for the light to clear on its own, as the underlying issue may worsen.

Q: Is P2402 the same on all vehicle brands?

The P2402 code definition — EVAP leak detection pump control circuit high — is standardized across OBD-II compliant vehicles (generally all 1996 and newer cars sold in the US). However, the exact location of the EVAP leak detection pump, the wiring diagram, and diagnostic procedures vary significantly between manufacturers and models. Always consult a vehicle-specific service manual or a professional when in doubt.

Abstract

The P2402 error code means your vehicle's onboard diagnostic system has detected a high voltage or open circuit condition in the EVAP (Evaporative Emission Control) leak detection pump control circuit. This pump is responsible for pressurizing the fuel vapor system so the ECM can check for leaks that could release harmful hydrocarbons into the atmosphere. While your car will typically still drive, this code will cause a failed emissions test and should be addressed promptly to avoid potential fuel vapor leaks and secondary damage.