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Cadillac U164E

: If symptom is related to a phone issue, please also make sure the customers phone is fully u

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact an authorized Cadillac service center to check the vehicle identification number, stored DTCs, radio software level, and applicability of the cited manufacturer communications.
Confidence95%

Quick answer

For Cadillac U164E, verified NHTSA manufacturer communications identify this DTC in radio/infotainment-related guidance. A software anomaly is documented in certain bulletin contexts, and the bulletin says not to replace the radio for the listed DTCs. Exact applicability to the supplied Cadillac EVs is not yet established by the bulletin excerpts 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 U164E mean?

For Cadillac U164E, verified NHTSA manufacturer communications identify this DTC in radio/infotainment-related guidance. A software anomaly is documented in certain bulletin contexts, and the bulletin says not to replace the radio for the listed DTCs. Exact applicability to the supplied Cadillac EVs is not yet established by the bulletin excerpts alone.

2. Technical explanation

The supplied diagnostic record labels U164E with a truncated phone-related note, so a complete code definition is not established by the verified evidence. Multiple NHTSA-posted Cadillac manufacturer communications (PIT6393D through PIT6393L) list U164E among radio-related DTCs. Several of those communications state that the listed DTCs can set because of a software anomaly and instruct technicians not to replace the radio for those DTCs. They reference a radio software update procedure where applicable. The evidence also mentions that, when a symptom is related to a phone issue, the customer's phone should be fully updated; the remainder of that instruction is truncated in the supplied evidence.

3. What system is affected?

Radio/infotainment system, based on the NHTSA manufacturer communication excerpts.

4. How serious is this code?

Unknown. The supplied record does not establish a severity classification.

5. Symptoms you may notice

  • A phone-related symptom is referenced in the supplied manufacturer communication excerpt, but the specific symptom is not stated.
  • Other symptoms are not yet established by verified evidence.

6. Possible causes

  • A software anomaly is documented in certain Cadillac radio-related bulletin contexts for U164E.
  • Other causes are 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

  • If the concern is phone-related, ensure the phone is fully updated, as referenced in the manufacturer communication excerpt.
  • Arrange diagnosis by an authorized Cadillac service center if U164E is present or infotainment/phone concerns persist.
  • Do not replace radio components based solely on this code; the cited manufacturer communications specifically advise against radio replacement for their listed DTC context.

10. Step-by-step troubleshooting

  1. Have a service center confirm whether the vehicle and concern are covered by the applicable Cadillac radio software bulletin or referenced campaigns 25-NA-085 or 25-NA-183.
  2. A technician should evaluate applicable radio software updates using the manufacturer procedure. The supplied evidence does not establish a consumer-performed update process.
  3. No additional troubleshooting steps are established by verified evidence.

11. When to contact service

Contact an authorized Cadillac service center to check the vehicle identification number, stored DTCs, radio software level, and applicability of the cited manufacturer communications.

12. What the service center may check

  • Confirm U164E and any accompanying DTCs with appropriate diagnostic equipment.
  • Check whether the vehicle is listed in 25-NA-085 or 25-NA-183 when applicable, as referenced in PIT6393K and PIT6393L.
  • Assess applicability of the relevant radio software update procedure.
  • For phone-related concerns, confirm the phone is fully updated, consistent with the cited communication excerpt.

13. Possible repair or resolution

  • Where applicable, Cadillac manufacturer communications describe a radio software update rather than radio replacement for U164E in the documented software-anomaly context.
  • A specific repair outcome for every U164E occurrence is not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • PIT6393D, NHTSA MC-11023907-0001, published 2025-10-01: Lists U164E among radio-related DTCs; includes a truncated note referring to fully updating the customer's phone for phone-related symptoms.
  • PIT6393E, NHTSA MC-11024438-0001, published 2025-10-04: States listed DTCs including U164E may set due to a software anomaly and advises not to replace the radio in that context.
  • PIT6393F, NHTSA MC-11024704-0001, published 2025-10-23: States listed DTCs including U164E may set due to a software anomaly and advises not to replace the radio in that context.
  • PIT6393H, NHTSA MC-11026861-0001, published 2025-12-23: States listed DTCs including U164E may set due to a software anomaly and advises not to replace the radio in that context.
  • PIT6393J, NHTSA MC-11029962-0001, published 2026-03-06: States listed DTCs including U164E may set due to a software anomaly and advises not to replace the radio in that context.
  • PIT6393K, NHTSA MC-11032554-0001, published 2026-04-28: Lists U164E and references a software update where required and vehicles listed in 25-NA-085 or 25-NA-183.
  • PIT6393L, NHTSA MC-11032781-0001, published 2026-05-14: Lists U164E and references a software update where required and vehicles listed in 25-NA-085 or 25-NA-183.
  • PIT6457B, NHTSA MC-11027686-0001, published 2026-01-12: Lists U164E among radio-related DTC keywords.

16. Recall information

  • No recall is established by the supplied verified evidence.

17. Official manufacturer information

Official NHTSA-posted manufacturer communications: https://static.nhtsa.gov/odi/tsbs/2025/MC-11023907-0001.pdf ; https://static.nhtsa.gov/odi/tsbs/2026/MC-11032781-0001.pdf

19. Frequently asked questions

What does Cadillac U164E mean?

The complete definition is not established by the supplied verified evidence. The record contains a truncated phone-related note, while NHTSA-posted Cadillac communications list U164E as a radio/infotainment-related DTC.

Does U164E require radio replacement?

Not in the documented software-anomaly bulletin context. Multiple cited Cadillac communications state not to replace the radio for the listed DTCs, including U164E.

Is there a known remedy?

The cited communications reference a radio software update where applicable. Whether it applies to a specific vehicle requires service verification.

Which vehicles are listed in the supplied applicability record?

The supplied record lists U.S. Cadillac CELESTIQ, LYRIQ, OPTIQ, and VISTIQ model-year ranges from 2023 through 2026, with overlapping 2024 through 2026 entries for some models. Bulletin applicability to each listed vehicle is not established by the excerpts alone.

20. Sources & verification

Verified
Cadillac U164E: : If symptom is related to a phone issue, please also… | EV Diagnostics