Verified EV diagnostic knowledge page

Toyota P0A1A

The warning lights and stored hybrid system DTCs can be triggered due to conditions detected not specific to the inverte

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a local Toyota dealer if you believe the vehicle has experienced the condition described in Toyota’s Customer Support Program. The dealer can confirm vehicle eligibility, diagnose the condition, and determine applicable coverage.
Confidence95%

Quick answer

For applicable U.S. Toyota Prius vehicles, P0A1A is listed by Toyota in a Customer Support Program concerning inverter/IPM-related failures. Contact a local Toyota dealer for diagnosis and coverage determination.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

Video guides

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Relevant videos play here without leaving this diagnostic page.

DTC Toyota P0A1A-793 Short ExplanationMaxidot Dodge
DTC Toyota P0A1A-791 Short ExplanationMaxidot Dodge
DTC Toyota P0A1A-659 Short ExplanationMaxidot Dodge

Videos are supporting material and never override OEM or regulator evidence.

1. What does P0A1A mean?

For applicable U.S. Toyota Prius vehicles, P0A1A is listed by Toyota in a Customer Support Program concerning inverter/IPM-related failures. Contact a local Toyota dealer for diagnosis and coverage determination.

2. Technical explanation

Verified Toyota/NHTSA communications identify P0A1A as one of the hybrid-system DTCs associated with a Customer Support Program that may cover IPM failure and other internal inverter components potentially damaged by IPM failure. The supplied evidence does not establish a universal technical definition of P0A1A or confirm that every occurrence is an IPM failure.

3. What system is affected?

Hybrid system inverter, including the intelligent power module (IPM) and potentially other internal inverter components damaged by IPM failure.

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

  • Toyota’s supplied program material associates the presence of P0A1A with possible IPM failure and potentially damaged internal inverter components. Whether this is the cause in an individual vehicle must be determined by Toyota dealer diagnosis.

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 diagnosis with a local Toyota dealer.
  • Provide the dealer with DTC P0A1A and ask whether the applicable Customer Support Program applies.
  • Do not attempt high-voltage inverter or IPM repair yourself.

10. Step-by-step troubleshooting

  1. A Toyota dealer should diagnose the vehicle and determine whether the IPM or other internal inverter components have failed.
  2. The supplied evidence does not establish owner-performed diagnostic steps for P0A1A.

11. When to contact service

Contact a local Toyota dealer if you believe the vehicle has experienced the condition described in Toyota’s Customer Support Program. The dealer can confirm vehicle eligibility, diagnose the condition, and determine applicable coverage.

12. What the service center may check

  • Confirm that P0A1A is present.
  • Diagnose the inverter/IPM and assess whether other internal inverter components were potentially damaged by IPM failure.
  • Verify eligibility for the applicable Toyota Customer Support Program based on the vehicle and program requirements.

13. Possible repair or resolution

  • Toyota’s program materials state that, where applicable, coverage may include repair or replacement of the IPM and other internal inverter components potentially damaged by IPM failure.
  • The required repair for an individual vehicle is not yet established by verified evidence and requires dealer diagnosis.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Toyota Customer Confidence Program 23TE03: 20-year coverage with no mileage limitation from date of first use for IPM and inverter-related conditions associated with DTCs P0A94, P0A1A, P324E, or P3004, as described in the supplied NHTSA manufacturer communications.
  • Toyota 20TE10 FAQ: P0A1A is listed among DTCs indicating the program condition; the program covers IPM failure and other internal inverter components potentially damaged by IPM failure when program conditions are met.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Official NHTSA-hosted Toyota communications: 23TE02/23TE03 information, https://static.nhtsa.gov/odi/tsbs/2023/MC-10240055-9999.pdf; 23TE02-1, https://static.nhtsa.gov/odi/tsbs/2023/MC-10235231-9999.pdf; 20TE10 FAQ, https://static.nhtsa.gov/odi/tsbs/2020/MC-10182972-9999.pdf.

19. Frequently asked questions

What should an owner do if P0A1A is present?

Toyota’s FAQ says an owner who believes they have experienced the covered condition should contact a local Toyota dealer. The dealer can diagnose the vehicle and determine whether program coverage applies.

Is P0A1A covered by Toyota?

The supplied Toyota communications list P0A1A in a Customer Support Program for applicable vehicles and conditions. Eligibility and coverage must be confirmed by a Toyota dealer.

What parts may be covered?

The supplied 20TE10 FAQ states that the program covers IPM failure and other internal inverter components potentially damaged by IPM failure when the listed DTCs, including P0A1A, are present and program conditions are met.

Does P0A1A mean the IPM has definitely failed?

No. The supplied evidence associates P0A1A with a program involving IPM and inverter-related failures, but does not establish that every P0A1A event confirms IPM failure.

20. Sources & verification

ReferenceVerified
Toyota P0A1A: The warning lights and stored hybrid system DTCs can be… | EV Diagnostics