P2402🔧 Evaporative emissions (EVAP leak detection pump)Drive with caution, fix soon

P2402: EVAP Leak Detection Pump Control Circuit High (Meaning, Causes, Fixes)

Reviewed 2026-10-24 · Based on 4 cited source(s)

What P2402 means

Many cars have a small electric leak detection pump, usually near the charcoal canister or fuel tank, that pulls a vacuum on the EVAP system to check it for leaks. RepairPal explains that the engine computer runs this test with the car off after it has been sitting for a few hours, and sets P2402 if it doesn't see the pump turn on as requested or doesn't see vacuum build. The manufacturers describe the trigger differently. Toyota (2007 Matrix and RAV4 manuals) calls P2402 "leak detection pump stuck ON", judged from the reference pressure the pump makes during the key-off EVAP test, about 5 hours after the engine is shut off, with two-trip logic before the light comes on. Toyota also notes the pump is built into the canister pump module, together with the vent valve and reference orifice. Mazda (2008 MX-5 manual) sets it when the pump's load current during the EVAP monitor is higher than specified, giving a pending code on the first drive cycle and turning on the light after two. Subaru (Crosstrek manual) flags it immediately when the computer sees an abnormally high pump control output. So check the factory procedure for your make.

Severity: can I keep driving?

Drive with caution, fix soon

Not an emergency, but get it diagnosed within a reasonable time. RepairPal rates P2402 as Moderate. The leak detection pump only runs the fuel-vapor leak test, so the car usually drives normally, but with this code set the EVAP leak test can't do its job and the check engine light will keep you from passing an emissions inspection in most areas.

Common symptoms

Likely causes

Roughly most to least common, based on the sources below. Your vehicle may differ.

  1. A failed leak detection pump, or on Toyotas a failed canister pump module that contains it (RepairPal, Toyota, Mazda)
  2. A short to power in the wire between the pump and the engine computer (Mazda, Subaru)
  3. Damaged, corroded or loose wiring or connectors (RepairPal, Toyota)
  4. A blocked or damaged EVAP hose or canister filter at the pump's air inlet (Toyota)
  5. A failed engine computer, which is rare (RepairPal, Toyota, Mazda)

Diagnostic steps you can do

⚠ Before you start

Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.

  1. Read all stored codes and freeze frame data. Note any other EVAP codes, since on Toyotas several pump-module codes are diagnosed together.
  2. Check for technical service bulletins for your vehicle before buying parts.
  3. Find the leak detection pump or canister pump module (usually near the charcoal canister or fuel tank) and inspect its connector and wiring for damage, corrosion and looseness.
  4. On Toyotas, check the hose from the air inlet to the canister pump module and the canister filter for blockage or damage.
  5. With a multimeter and the factory specs you can check the pump's resistance and look for battery voltage on the control wire with the pump unplugged, as Mazda's procedure does.
  6. After a repair, clear the code. The leak test runs with the car off after several hours, so the code may take a few drive cycles to confirm the fix.

Typical fixes

Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.

🛠 When to call a pro

  • You need a scan tool that can run the EVAP system test or command the pump
  • The wiring checks out and you don't have factory specs for the pump
  • The code returns after replacing the pump or module
  • You need the light off for an inspection deadline

Where to buy

Plain search links. Always match parts to your exact year, make, model and engine.

OBD2 scanners on Amazon Parts at Advance Auto Parts catalog at RockAuto

FAQs

Is P2402 serious?

Not usually for driving. RepairPal rates it Moderate. The car typically runs normally, but the EVAP leak test can't work properly and the check engine light can fail an emissions inspection, so get it diagnosed soon.

Can a loose gas cap cause P2402?

None of the sources list the gas cap as a cause of P2402. It points to the leak detection pump, its wiring or the engine computer. A loose cap is more often linked to EVAP leak codes like P0455 and P0456.

Why does P2402 show up with P2401 and P2419 on my Toyota?

Toyota's manual diagnoses those codes together because they come from the same key-off EVAP test of the canister pump module, which holds the leak detection pump, the vent valve and the reference orifice.

How much does it cost to fix P2402?

None of these sources give a repair cost. It depends on whether it's a wiring repair, a pump or a full canister pump module, so get a written estimate after diagnosis.

Sources

  1. RepairPal: P2402 Evaporative Emission System Leak Detection Pump Control Circuit (rated Moderate)
  2. Toyota 2007 Matrix repair manual: DTC P2401/P2402 Leak Detection Pump Control Circuit Low/High
  3. Mazda 2008 MX-5 Miata workshop manual: DTC P2402 [LF] EVAP leak detection pump motor circuit high
  4. Subaru Crosstrek service manual: DTC P2402 EVAP System Leak Detection Pump Control Circuit High

Last reviewed 2026-10-24. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.