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Jeep P1B03

Resolver Signal / MCPA Rationality

DriveUnknown. The supplied evidence does not establish whether the vehicle can be driven with P1B03.
ChargeUnknown. The supplied evidence does not establish whether charging is permitted with P1B03.
ServiceContact an authorized Jeep dealer or qualified EV service provider for diagnosis, particularly if the vehicle displays an intermittent wrench/service indicator or experiences an EV-system shutdown condition.
Confidence95%

Quick answer

P1B03 is a Jeep DTC meaning “Resolver Signal / MCPA Rationality.” Verified evidence links it to certain U.S. Jeep Grand Cherokee and Wagoneer 2024 vehicles and Jeep Wrangler 2021–2023 vehicles. Official manufacturer communications identify applicable service procedures, but the supplied evidence does not establish a universal cause, repair, driving status, or charging status.

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 P1B03 mean?

P1B03 is a Jeep DTC meaning “Resolver Signal / MCPA Rationality.” Verified evidence links it to certain U.S. Jeep Grand Cherokee and Wagoneer 2024 vehicles and Jeep Wrangler 2021–2023 vehicles. Official manufacturer communications identify applicable service procedures, but the supplied evidence does not establish a universal cause, repair, driving status, or charging status.

2. Technical explanation

The verified diagnostic meaning for P1B03 is Resolver Signal / MCPA Rationality. Official Jeep manufacturer communications submitted to NHTSA list P1B03, in some cases as P1B03-00, among the qualifying DTCs for their procedures. The supplied evidence does not further define the technical failure mechanism or identify a component-level cause.

3. What system is affected?

Not yet established by verified evidence. The DTC title references resolver signal and MCPA rationality, but the supplied evidence does not specify the affected vehicle system.

4. How serious is this code?

Unknown. The supplied evidence does not provide a severity classification.

5. Symptoms you may notice

  • An intermittent wrench/service indicator is identified in manufacturer communications 08-003-25, 08-003-25 REV. A, and 08-231-24.
  • An EV-system shutdown while transferring is identified in manufacturer communications 08-059-25, 08-060-25, and 08-061-25. The supplied excerpt does not establish the full condition being transferred or the complete symptom description.

6. Possible causes

  • Not yet established by verified evidence.

7. Can I still drive the vehicle?

Unknown. The supplied evidence does not establish whether the vehicle can be driven with P1B03.

8. Can I charge the vehicle?

Unknown. The supplied evidence does not establish whether charging is permitted with P1B03.

9. What you can safely do

  • Arrange diagnosis by an authorized Jeep service facility or suitably qualified EV service professional.
  • Do not attempt high-voltage component diagnosis or repair based on this information.
  • If an EV-system shutdown or service indication occurs, use the vehicle only in accordance with the vehicle’s warnings and operating instructions; continued operation suitability is not established by the supplied evidence.

10. Step-by-step troubleshooting

  1. Have a service provider confirm the stored DTC(s), including whether P1B03 or P1B03-00 is present.
  2. Provide the vehicle year, model, U.S. market status, and all stored DTCs so the service provider can determine whether an applicable manufacturer communication applies.
  3. The detailed diagnostic steps are not established by the supplied evidence.

11. When to contact service

Contact an authorized Jeep dealer or qualified EV service provider for diagnosis, particularly if the vehicle displays an intermittent wrench/service indicator or experiences an EV-system shutdown condition.

12. What the service center may check

  • Confirm applicability by VIN, model year, model, and market.
  • Check for P1B03/P1B03-00 and any accompanying DTCs.
  • Review applicable Jeep manufacturer communications 08-231-24, 08-003-25, 08-003-25 REV. A, 08-059-25, 08-060-25, and 08-061-25 as appropriate. The supplied evidence does not include their complete procedures.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied records confirm that manufacturer communications exist, but do not provide the complete repair instructions or final repair outcome.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Jeep manufacturer communication 08-231-24, published November 1, 2024; NHTSA communication 11010255. It lists P1B03 among qualifying DTCs and identifies an intermittent wrench/service indicator in the supplied excerpt.
  • Jeep manufacturer communication 08-003-25, published January 9, 2025; NHTSA communication 11012823. It lists P1B03 among qualifying DTCs and identifies an intermittent wrench/service indicator in the supplied excerpt.
  • Jeep manufacturer communication 08-003-25 REV. A, published June 14, 2025; NHTSA communication 11019623. It lists P1B03 among qualifying DTCs and identifies an intermittent wrench/service indicator in the supplied excerpt.
  • Jeep manufacturer communications 08-059-25, 08-060-25, and 08-061-25, each published March 7, 2025; NHTSA communications 11015532, 11015533, and 11015534. Their supplied excerpts list P1B03-00 among qualifying DTCs and identify an EV-system shutdown while transferring. Exact applicability and procedures are not established by the supplied excerpts.

16. Recall information

  • Not yet established by verified evidence. No recall information was supplied.

17. Official manufacturer information

Verified official sources are NHTSA-hosted Jeep manufacturer communications: 11010255 (08-231-24), 11012823 (08-003-25), 11019623 (08-003-25 REV. A), 11015532 (08-059-25), 11015533 (08-060-25), and 11015534 (08-061-25).

19. Frequently asked questions

What does Jeep code P1B03 mean?

The verified meaning is “Resolver Signal / MCPA Rationality.”

Which vehicles are verified as applicable?

The supplied applicability data identifies U.S.-market Jeep Grand Cherokee 2024, Wagoneer 2024, and Wrangler 2021, 2022, and 2023 vehicles. VIN-level applicability is not established by the supplied evidence.

Can P1B03 cause a service warning?

Yes. The supplied excerpts for communications 08-231-24, 08-003-25, and 08-003-25 REV. A identify an intermittent wrench/service indicator among customer experiences, but do not establish that it occurs in every case.

Can P1B03 be associated with EV-system shutdown?

The supplied excerpts for communications 08-059-25, 08-060-25, and 08-061-25 identify EV-system shutdown while transferring among customer experiences when P1B03-00 is one of the listed DTCs. The excerpts do not establish that P1B03 alone causes this condition in every vehicle.

Is there a verified repair?

Not from the supplied evidence. Manufacturer communications are identified, but their complete repair procedures and outcomes were not supplied.

20. Sources & verification

Verified
Jeep P1B03: Resolver Signal / MCPA Rationality | EV Diagnostics