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Audi P251500

Refrigerant pressure sensor 2 electrical fault. Technical Background A failure of the sensor electronics causes a loss of pressure evaluation. The sensor with base part number 4M09

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact an Audi dealer or qualified workshop for diagnosis, especially if the cabin air conditioning does not cool and P251500 is stored.
Confidence95%

Quick answer

P251500 is an Audi thermal-management DTC for an electrical fault in refrigerant pressure sensor 2. Audi documentation links it to loss of pressure evaluation and reports that cabin air conditioning may not cool, sometimes intermittently.

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 P251500 mean?

P251500 is an Audi thermal-management DTC for an electrical fault in refrigerant pressure sensor 2. Audi documentation links it to loss of pressure evaluation and reports that cabin air conditioning may not cool, sometimes intermittently.

2. Technical explanation

Audi identifies P251500 as “Refrigerant pressure sensor 2 electrical fault.” Its technical background states that failure of the sensor electronics causes loss of pressure evaluation. The relevant control module is Thermal management J1024, address word 00C5. Audi’s bulletin identifies sensors with base part number 4M0959603 and a build date before calendar week 31 of 2021 as being at issue (G395/G827), and states that an improved sensor was implemented in production.

3. What system is affected?

Thermal management / air-conditioning refrigerant pressure evaluation; Thermal management J1024 (address word 00C5).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • The air-conditioning system does not cool the cabin.
  • The no-cooling condition may be intermittent.
  • P251500 may be stored in Thermal management J1024 (address word 00C5).

6. Possible causes

  • Audi states that a failure of refrigerant pressure sensor 2 electronics causes loss of pressure evaluation.
  • Audi identifies sensor base part number 4M0959603 with a build date before calendar week 31 of 2021 as being at issue (G395/G827).

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 by an Audi service provider or qualified workshop.
  • Use the applicable Audi technical service bulletin as a reference when reporting the concern.
  • Do not attempt refrigerant-system or high-voltage-system repair based on this information.

10. Step-by-step troubleshooting

  1. Confirm whether P251500 is stored in Thermal management J1024, address word 00C5.
  2. Verify whether the reported condition is lack of cabin air-conditioning cooling, including intermittent loss of cooling.
  3. Have a qualified workshop determine whether the affected refrigerant pressure sensor matches Audi’s identified part/build-date criteria.

11. When to contact service

Contact an Audi dealer or qualified workshop for diagnosis, especially if the cabin air conditioning does not cool and P251500 is stored.

12. What the service center may check

  • Check Thermal management J1024 (address word 00C5) for P251500.
  • Confirm the customer-reported cabin cooling concern.
  • Identify the refrigerant pressure sensor part/build-date status against Audi’s bulletin criteria.
  • Follow the applicable Audi service bulletin diagnostic and repair procedure.

13. Possible repair or resolution

  • Audi states that an improved sensor was implemented in production.
  • The specific field repair resolution is not fully established by the supplied verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Audi Technical Service Bulletin A8723382068460_2, published January 31, 2023; NHTSA manufacturer communication MC-10230992-0001.
  • Audi Technical Service Bulletin A8722352068460_1, published November 9, 2022; NHTSA manufacturer communication MC-10226899-0001.

16. Recall information

  • No recall information is established by the supplied verified evidence.

17. Official manufacturer information

Official NHTSA-hosted Audi communications: https://static.nhtsa.gov/odi/tsbs/2023/MC-10230992-0001.pdf and https://static.nhtsa.gov/odi/tsbs/2022/MC-10226899-0001.pdf

19. Frequently asked questions

What does Audi code P251500 mean?

Audi defines P251500 as “Refrigerant pressure sensor 2 electrical fault.”

What condition may occur with P251500?

Audi reports that the cabin air-conditioning system may not cool, and the condition may be intermittent.

Which vehicles are covered by the supplied Audi applicability data?

US-market 2020–2022 Audi A7, A8, Q5, RS e-tron GT, e-tron, and e-tron GT models.

Is it safe to drive or charge with P251500?

Not yet established by verified evidence.

20. Sources & verification

Verified
Audi P251500: Refrigerant pressure sensor 2 electrical fault.… | EV Diagnostics