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Cadillac U2426

voltage battery surge tank and document via photo. 3. Observe and record the Battery Energy Control Module parameter(s); K16– Battery Energy Control Module -> Data Display -> High

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a Cadillac dealer or qualified technician trained for high-voltage EV service. Bulletin evidence states that repairs must be performed by a technician who has successfully completed required training.
Confidence95%

Quick answer

U2426 is included in Cadillac bulletin 23-NA-151 diagnostic criteria for specified Cadillac EVs. The supplied record’s title/meaning is truncated procedural text and does not establish a standalone code definition.

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 U2426 mean?

U2426 is included in Cadillac bulletin 23-NA-151 diagnostic criteria for specified Cadillac EVs. The supplied record’s title/meaning is truncated procedural text and does not establish a standalone code definition.

2. Technical explanation

Verified bulletin evidence instructs trained technicians to evaluate U2426 as part of a high-voltage battery diagnostic process. The procedure includes documenting high-voltage battery surge-tank coolant level and recording Battery Energy Control Module high-voltage isolation data. This evidence does not establish that U2426 alone identifies a specific failed component or condition.

3. What system is affected?

High-voltage battery diagnostic process, including the Battery Energy Control Module and high-voltage battery surge tank.

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 assessment by a Cadillac dealer or technician with the required high-voltage training.
  • Do not attempt high-voltage battery diagnosis or repair yourself.

10. Step-by-step troubleshooting

  1. A trained technician should verify whether U2426 is current, as directed by the applicable revision of bulletin 23-NA-151.
  2. The bulletin directs documentation of coolant level in the high-voltage battery surge tank, including a photo.
  3. The bulletin directs recording Battery Energy Control Module high-voltage isolation data, including most recent isolation resistance information where specified.
  4. The applicable bulletin revision should be consulted because its listed DTC criteria and procedure details changed over time.

11. When to contact service

Contact a Cadillac dealer or qualified technician trained for high-voltage EV service. Bulletin evidence states that repairs must be performed by a technician who has successfully completed required training.

12. What the service center may check

  • Verify U2426 status according to the applicable 23-NA-151 revision.
  • Document high-voltage battery surge-tank coolant level with a photo.
  • Record Battery Energy Control Module high-voltage isolation data.
  • Review the vehicle under the applicable version of Cadillac bulletin 23-NA-151.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied bulletin summaries describe diagnostic documentation and evaluation, not a confirmed repair for U2426 alone.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Cadillac 23-NA-151, published through NHTSA manufacturer communications, includes U2426 in its diagnostic criteria.
  • NHTSA MC-11017886-0001, published April 9, 2025, is a revised 23-NA-151 version that added Cadillac VISTIQ and updated information and service-procedure steps.
  • NHTSA MC-11012693-0001, published December 11, 2024, lists U2426 among DTCs to verify as current.
  • NHTSA MC-10245234-0001, published October 19, 2023, lists U2426 and describes surge-tank coolant documentation and Battery Energy Control Module isolation-data recording.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Official NHTSA-hosted manufacturer communication: Cadillac bulletin 23-NA-151, including https://static.nhtsa.gov/odi/tsbs/2025/MC-11017886-0001.pdf

19. Frequently asked questions

What does U2426 mean?

The supplied verified evidence does not provide a standalone definition. Its stored title/meaning contains truncated service-procedure text, while bulletin 23-NA-151 lists U2426 as a DTC used in its diagnostic criteria.

Which vehicles are covered by the supplied applicability data?

Cadillac LYRIQ model years 2023–2026 in the US and Cadillac VISTIQ model years 2023–2026 in the US. The overlapping LYRIQ applicability entries support the combined 2023–2026 range.

Is U2426 covered by a recall?

Not yet established by verified evidence.

Can I keep driving or charging?

Not yet established by verified evidence. Seek qualified Cadillac EV service rather than attempting high-voltage diagnosis yourself.

20. Sources & verification

Verified
Cadillac U2426: voltage battery surge tank and document via photo. 3.… | EV Diagnostics