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Cadillac U2BFC

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.
ServiceService is appropriate because the relevant GM bulletin states that its procedure must be performed by a technician who has successfully completed the required training.
Confidence95%

Quick answer

For Cadillac LYRIQ and VISTIQ applications listed below, U2BFC is included in GM bulletin 23-NA-151. The supplied evidence does not establish a plain-language DTC definition, drivability status, charging status, or a specific repair for U2BFC alone.

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 U2BFC mean?

For Cadillac LYRIQ and VISTIQ applications listed below, U2BFC is included in GM bulletin 23-NA-151. The supplied evidence does not establish a plain-language DTC definition, drivability status, charging status, or a specific repair for U2BFC alone.

2. Technical explanation

GM bulletin 23-NA-151 includes U2BFC among DTCs for a high-voltage battery diagnostic procedure. The procedure directs a qualified technician to document coolant level in the high-voltage battery surge tank and record Battery Energy Control Module high-voltage isolation data, including the most recent isolation-resistance value for the pack (and Pack 2 if equipped). The supplied database title/meaning text appears to be a procedure excerpt rather than a verified code definition.

3. What system is affected?

High-voltage battery / Battery Energy Control Module diagnostic process. A more specific affected component is not yet established by verified evidence.

4. How serious is this code?

Unknown. The supplied verified evidence does not assign a severity level.

5. Symptoms you may notice

  • Not yet established by verified evidence.

6. Possible causes

  • Not yet established by verified evidence for U2BFC alone.

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 a Cadillac/GM service facility or a technician qualified for the required high-voltage battery training.
  • Do not attempt high-voltage battery diagnosis or repair yourself.
  • Record the DTC and retain any scan report for the service visit.

10. Step-by-step troubleshooting

  1. GM bulletin 23-NA-151 directs a trained technician to verify whether listed DTCs, including U2BFC, are current or history.
  2. The bulletin directs visual inspection and photographic documentation of coolant level in the high-voltage battery surge tank.
  3. The bulletin directs recording Battery Energy Control Module high-voltage isolation data, including most recent isolation resistance for the pack and Pack 2 when equipped.

11. When to contact service

Service is appropriate because the relevant GM bulletin states that its procedure must be performed by a technician who has successfully completed the required training.

12. What the service center may check

  • Verify U2BFC status as current or history.
  • Inspect and document high-voltage battery surge-tank coolant level with a photo.
  • Record Battery Energy Control Module high-voltage isolation data, including most recent pack isolation resistance and Pack 2 if equipped.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied excerpts identify diagnostic documentation steps but do not establish a U2BFC-specific repair outcome.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM Bulletin 23-NA-151, published versions reflected in NHTSA manufacturer communications dated September 5, 2023; October 19, 2023; and April 9, 2025. U2BFC is listed in the bulletin's diagnostic context.
  • Official source: https://static.nhtsa.gov/odi/tsbs/2025/MC-11017886-0001.pdf

16. Recall information

  • No recall is established by the supplied verified evidence.

17. Official manufacturer information

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

19. Frequently asked questions

What does U2BFC mean?

A plain-language definition is not established by the supplied verified evidence. The provided canonical text is a diagnostic-procedure excerpt, and GM bulletin 23-NA-151 lists U2BFC among DTCs covered by its high-voltage battery diagnostic process.

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 supplied data also contains a narrower LYRIQ 2023-2024 entry.

Is U2BFC covered by a service bulletin?

Yes. GM bulletin 23-NA-151 lists U2BFC and provides technician-directed high-voltage battery diagnostic documentation steps.

20. Sources & verification

Verified
Cadillac U2BFC: voltage battery surge tank and document via photo. 3.… | EV Diagnostics