Subaru P0456
This is an example of a completed self-test, with “P2404” set after being performed: Evap System Absolute Pressure (Phase A) was not changed. CONTINUED ON THE NEXT PAGE Special Edi
Quick answer
Verified evidence identifies P0456 as appearing in an example of a completed EVAP self-test in a Subaru TechTIPS communication. The supplied evidence does not establish a vehicle-specific fault definition, cause, severity, drivability, charging impact, or repair for P0456.
This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.
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1. What does P0456 mean?
Verified evidence identifies P0456 as appearing in an example of a completed EVAP self-test in a Subaru TechTIPS communication. The supplied evidence does not establish a vehicle-specific fault definition, cause, severity, drivability, charging impact, or repair for P0456.
2. Technical explanation
The verified NHTSA-hosted Subaru TechTIPS document includes an example of a completed self-test with P0456 set. Its supplied excerpt also refers to EVAP leak diagnosis and separately mentions P2404 and EVAP system absolute pressure results. The evidence provided does not state what condition specifically triggers P0456.
3. What system is affected?
EVAP system is referenced by the verified Subaru TechTIPS evidence. No further system detail is established by the supplied evidence.
4. How serious is this code?
Not yet established by verified evidence.
5. Symptoms you may notice
Not yet established by verified evidence.
6. Possible causes
- Not yet established by verified evidence.
7. Can I still drive the vehicle?
Not yet established by verified evidence.
8. Can I charge the vehicle?
Not yet established by verified evidence.
9. What you can safely do
- Arrange professional diagnosis if the code is present or returns after clearing.
- Do not perform high-voltage repairs or procedures; no high-voltage repair instruction is supported by the verified evidence.
10. Step-by-step troubleshooting
- Use the applicable Subaru diagnostic information and a qualified service provider to evaluate the stored DTC and self-test results.
- The supplied verified evidence does not establish a step-by-step diagnostic procedure for P0456.
11. When to contact service
Contact a Subaru dealer or qualified service provider for diagnosis, particularly if P0456 remains stored or recurs.
12. What the service center may check
- Confirm the vehicle model, model year, and region before applying Subaru information.
- Retrieve stored DTCs and applicable self-test results.
- The supplied evidence does not establish additional P0456-specific inspection or test steps.
13. Possible repair or resolution
- Not yet established by verified evidence.
14. Affected vehicles
- Subaru Crosstrek · 2019–2023 · US
- Subaru Solterra · 2019–2023 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication PDF 10219476: Subaru Tech Tips, published August 12, 2022. The supplied excerpt includes an example of a completed EVAP self-test with P0456 set and a summary of EVAP leak diagnosis.
16. Recall information
- Not yet established by verified evidence.
17. Official manufacturer information
Verified source: NHTSA-hosted Subaru Tech Tips, Manufacturer Communication PDF 10219476, published 2022-08-12: https://static.nhtsa.gov/odi/tsbs/2022/MC-10219476-0001.pdf
19. Frequently asked questions
What does the verified evidence say about P0456?
It says P0456 was set in an example of a completed EVAP self-test within Subaru TechTIPS material. A specific P0456 definition is not established by the supplied excerpt.
Which vehicles are covered by the supplied applicability data?
The supplied data lists US-market Subaru Crosstrek and Subaru Solterra vehicles for model years 2019 through 2023. Applicability should be confirmed for the individual vehicle before using the information.
Is P0456 related to P2404?
The same supplied document excerpt shows separate examples with P0456 and P2404 set. It does not establish that the codes have the same cause or repair.