Cavox Research Team · case log

P2401 on Toyota & Scion: the cases behind the evidence

What this page is
The report at P2401 in Toyota: EVAP Leak Detection Pump Circuit Low — Causes, Severity, Fix is built on 12 federal complaint records — read as 11 distinct cases, pulled 2026-07-03 from NHTSA. Below them are 1 publicly verifiable records from forums, Reddit, and YouTube. They came from 16 reviewed discussions; 15 records were excluded from the public proof layer (1 were not proven single-vehicle journeys, 11 without a verified outcome). They are shown as evidence, not folded into the report's federal counts.
Inclusion rule

Federal: every NHTSA complaint whose narrative names P2401 on Toyota or Scion vehicles — the complete set at pull time, nothing sampled.

Community: every admitted record is either an owner account or a documented repair case for one Toyota or Scion vehicle with P2401; it has an immutable raw receipt, exact source excerpt, and public HTTPS verification link. General explainers, sources behind login or a paywall, and sources without a substantive verbatim excerpt stay out of this public layer. Counting rules: /methodology.

Federal records — NHTSA (12)
2006 Scion Tcfederal record ↗

ODI-10605429 · filed 2014-06-23 · 150,000 mi

“P043E, PO444F, P2401,P2402,P2419 CODES CHARCOAL CANISTER ASSEMBLY FAILED SEEMS TO BE A VERY COMMON PROBLEM WITH THIS PARTICULAR TOYOTA MODEL AND TOYOTA SHOULD…”
canister / pump namedTSB cited
2006 Scion Xafederal record ↗

ODI-10263297 · filed 2009-03-27 · mileage not stated

“I OWN A 2006 SCION XA. I BOUGHT THE CAR NEW OFF OF THE SHOW ROOM. AFTER 5 MONTHS OF OWNING THE CAR THE CHECK ENGINE LIGHT CAME ON. I TOOK THE CAR BACK TO THE…”
canister / pump named
2006 Scion Xafederal record ↗

ODI-10289046 · filed 2009-10-20 · 58,734 mi

“I OWN A 2006 SCION XA AND VERY RECENTLY THE CHECK ENGINE LIGHT CAME ON. I HAD IT DIAGNOSED..."P2401 EVAPORATE LEAK DETECTION PUMP CONTROL CIRCUIT". THE…”
canister / pump namedwater intrusion
2006 Scion Xafederal record ↗

ODI-10550421 · filed 2013-10-31 · 46,500 mi

“SCION XA 2006 WITH JUST 46000 (MOSTLY HIGHWAY!) MILES DID NOT PASS EMISSIONS TEST DUE TO DIAGNOSTIC CODES: P2401, P043E, PO43F, P2419, P2402 INDICATING…”
canister / pump namedcost namedTSB cited
2006 Scion Xafederal record ↗

ODI-10820387 · filed 2016-01-15 · 105,000 mi

“BOUGHT A 2006 SCION XA THAT PREVIOUSLY HAD THE CHARCOAL CANISTER ASSEMBLY AND FUEL FILLER PIPE COVER REPLACED UNDER TSB EG047-06. CEL WAS ON WHEN I BOUGHT THE…”
canister / pump namedTSB citedwater intrusion
2006 Scion Xafederal record ↗

ODI-10957001 · filed 2017-02-26 · 100,000 mi

“HAWAII IN THE HOUSE ...I OWN A 2006 SCION XA AND RECENTLY THE CHECK ENGINE LIGHT CAME ON. I HAD IT DIAGNOSED AT HILO TOYOTA.."P2401 EVAPORATE LEAK DETECTION…”
canister / pump namedcost namedwater intrusion
2006 Scion Xafederal record ↗

ODI-10969318 · filed 2017-03-29 · 84,000 mi

“2006 SCION XA CHECK ENGINE LIGHT WITH DIAGNOSTIC CODES: P2401, P043E, P043F, P2419, P2402 INDICATING "EVAPORATION LEAK/EMISSION PROBLEMS." THERE APPARENTLY ARE…”
cost namedTSB cited
2007 Toyota Corollafederal record ↗

ODI-11387241 · filed 2021-01-08 · 130,000 mi

“STARTED CAR THIS MORNING AND THE CHECK ENGINE LIGHT CAME ON. TOOK TO PARTS STORE AND HOOKED IT UP TO THE COMPUTER AND FOUND CODES (P2401, P043E, P043F, P2402,…”
canister / pump namedwiring suspected
2009 Toyota Corolla Matrixfederal record ↗

ODI-11533362 · filed 2023-07-19 · mileage not stated

“Known well issues, faulty thank getting water to canister. Car Scanner ELM OBD2 Version: 1.99.2/1.99.2/iOS DTC report Connection profile: Toyota 2006-2009…”
canister / pump namedwater intrusion
2017 Toyota Rav4federal record ↗

ODI-11419086 · filed 2021-05-31 · mileage not stated

“Recurring Problems with AWD Malfunction, Engine Light On. Contacted Toyota two month ago, No reply from Toyota; Description of Complaints: On March 19, 2021, I…”
2007 Toyota Yaris H/Bfederal record ↗

ODI-10442353 · filed 2012-01-04 · 125,000 mi

“EXPERIENCED FAILURE OF EMISSIONS EVAP SYSTEM DUE TO WATER INTRUSION THROUGH POORLY DESIGNED COMPONENTS. CHECK ENGINE LAMP (CEL) ILLUMINATED CONSTANT ON DURING…”
canister / pump namedcost namedTSB citedwater intrusion
2007 Toyota Yaris H/Bfederal record ↗

ODI-10694017 · filed 2015-03-13 · 830,000 mi

“EXPERIENCED FAILURE OF EMISSIONS EVAP SYSTEM DUE TO WATER INTRUSION THROUGH POORLY DESIGNED COMPONENTS. CHECK ENGINE LAMP (CEL) ILLUMINATED CONSTANT ON DURING…”
canister / pump namedcost namedTSB citedwater intrusion
Community cases — role-validated records (1 · 1 reddit)
These are role-validated public diagnostic or repair records linked to their sources. Because community posts are self-selected, every admitted record is shown, but the records are not turned into a percentage. The report's counted numbers stay on the federal lane.
2010 Toyota Corollaredditowner account

posted 2024-10-29 · mileage not stated

“I've been trying to search online for solutions to these codes on my 2010 Corolla, and figure I should likely take it to a Toyota dealership instead of my…”

Attempts mentioned: vapour canister; purge valve

Thread status: no verified final outcome was posted

canister / pump named

view thread ↗ · archived 2026-07-27 ↗

How to read this log
Signal tags & bias

Signal tags are machine-applied with a code-specific, versioned wordlist (v1.0). In the federal lane: canister / pump named 10 · water intrusion 6 · TSB cited 6 · wiring suspected 1 · cost named 5. The same chips orient community records but are not counted there. Quoted excerpts are checked against immutable source receipts. Structured symptom and attempt lines render only when the exact phrase is also present in that receipt.

Federal bias: federal complaints are self-selected — owners file when a problem is expensive, unresolved, or felt as a safety issue, so this set skews toward bad outcomes and says nothing about how often the code sets in the first place. Implausible odometer entries are kept verbatim; they are treated as possible typos in prose, never silently corrected.

Community bias: public discussion records are self-selected — they are richer on what was tried, what reportedly changed, and what it cost than on incidence. A record can be an owner account or a documented repair case; neither proves fleet prevalence.. Threads can disappear; when an archive snapshot exists the row links to it, otherwise it is marked live-only.

Download the public data (JSON) — a whitelisted projection of the same dataset that renders this log. Report an error.