OBD-II Code · Emissions
P2401
EVAP Leak Detection Pump Control Circuit Low
Severity
low
Lowest on our scale. Fix it when convenient.
Can you drive it
Only if running normally
A short trip to a shop may be reasonable if the light is steady and the car runs normally. Stop safely for a flashing light, severe shaking, overheating, loss of power, or another urgent warning. The code alone cannot confirm safety.
Indicative cost (USD)
$150–$400
Varies by vehicle, diagnosis, parts, and local labor. This is not a repair quote.
EVAP leak detection pump low voltage.
How a shop works this
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed.
Note every code that is set, not just this one.
Codes that appear together usually narrow the cause faster than any one of them read alone.
Read the freeze frame — the conditions the fault was recorded under.
Cold or warm, idle or load, road speed and engine speed. A fault that only appears cold is a different fault from one that only appears under load, even with the same code on the scanner.
Confirm the fault is current rather than history.
Clear the code and see whether it returns under those same conditions. A code that does not come back may have been logged during a repair, a flat battery, or a bad connection that has since been disturbed.
Then work the likely-causes list in the order shown.
That order is what a shop checks first for this code — wiring and connections before the component they run to, because a connector costs nothing to inspect and is a common answer.
If the code comes back after a repair, the underlying fault is still there. That is the point to bring in a scanner with live data and freeze-frame, or a shop that has one.
Common symptoms
- Check engine light
Likely causes
- Failed pumpMost common
- Wiring short
Read the full diagnostic procedureP2401 means the ECM is seeing the EVAP Leak Detection Pump control circuit pulled low — voltage on the control pin is sitting near ground when it sho…
P2401 means the ECM is seeing the EVAP Leak Detection Pump control circuit pulled low — voltage on the control pin is sitting near ground when it should be at battery voltage with the driver off, indicating a short to ground in the harness or a shorted solenoid winding. With the connector unplugged you should read battery voltage on the ECM-side control wire when KOEO and the pump commanded off (driver high-side disengaged); on the pump side, solenoid resistance should be 30-80 ohms across the two pins.
Cheapest-first ladder
- pull the connector at the pump and check whether the code transitions to P2400 (open) — if it does, the short is inside the pump or at the connector itself, not in the harness.
- Inspect the pigtail for melted insulation where the harness clips to the chassis (rear-axle pumps get rock-strike abrasion), measure the control pin to chassis ground with the connector unplugged (less than 100 ohms = harness short, infinite = harness OK), and current-clamp the supply circuit during a commanded activation (a shorted coil pulls more than 1.5A and trips the ECM's protection).
- Expensive misdiagnosis caveat: VW/Audi/Chrysler LDP is mounted in a notorious water-collection point above the rear axle — corrosion at the connector is the #1 root cause; replace the pigtail before replacing the pump, and check for a chafed harness where it crosses the rear subframe before assuming the pump itself shorted internally.
Vehicle-specific patterns1998-2009 VW/Audi (Jetta, Passat, Golf, A4, A6) frequently throws P2401 from a chafed-through harness where the EVAP loom crosses the rear axle beam…
- 1998-2009VW/Audi (Jetta, Passat, Golf, A4, A6) frequently throws P2401 from a chafed-through harness where the EVAP loom crosses the rear axle beam — the insulation wears through and the control wire grounds against the chassis.
- 1998-2008Chrysler/Jeep/Dodge (Sebring, Wrangler, Grand Cherokee) NVLD/LDP combination units short internally when water intrudes past the seal at the top of the unit, and the fix is the full assembly.
- 1996-2005Mercedes-Benz (W202, W203, W211) throws P2401 from a failed pump solenoid that shorts winding-to-case after the canister assembly heat-cycles for a decade. Common LDP repair pattern: replace pump + harness pigtail together; standalone pump replacement leaves the same root cause.
Estimated repair$180 to $700.
Look up another code
P2401 — frequently asked
What does a P2401 code mean?
EVAP leak detection pump low voltage.
What causes a P2401 code?
Common causes: Failed pump; Wiring short.
What are the symptoms of a P2401 code?
Typical symptoms: Check engine light.
Is it safe to drive with a P2401 code?
Only if running normally. A short trip to a shop may be reasonable if the light is steady and the car runs normally. Stop safely for a flashing light, severe shaking, overheating, loss of power, or another urgent warning. The code alone cannot confirm safety. Estimated repair: $150-$400.
How do I diagnose a P2401 code?
Work from evidence to part, not the other way round. A code names a circuit or a symptom; it does not name the part that failed. 1. Note every code that is set, not just this one. 2. Read the freeze frame — the conditions the fault was recorded under. 3. Confirm the fault is current rather than history. 4. Then work the likely-causes list in the order shown.
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