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Cadillac U164F

Created On 12/12/2025 - Updated Labor Time 01/12/2026 - Updated DTC list

DriveUnknown. The supplied verified evidence does not establish whether it is safe to drive with U164F present.
ChargeUnknown. The supplied verified evidence does not establish whether it is safe to charge with U164F present.
ServiceCadillac service should evaluate U164F using bulletin PIT6457B and applicable vehicle service information. Service urgency is not established by the supplied evidence.
Confidence95%

Quick answer

U164F is listed in Cadillac bulletin PIT6457B for certain 2023–2026 U.S. CELESTIQ, LYRIQ, OPTIQ, and VISTIQ vehicles. The supplied verified evidence does not establish the code’s definition, cause, symptoms, driving safety, charging safety, or repair procedure.

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 U164F mean?

U164F is listed in Cadillac bulletin PIT6457B for certain 2023–2026 U.S. CELESTIQ, LYRIQ, OPTIQ, and VISTIQ vehicles. The supplied verified evidence does not establish the code’s definition, cause, symptoms, driving safety, charging safety, or repair procedure.

2. Technical explanation

The verified source is NHTSA manufacturer communication MC-11027686-0001, Cadillac bulletin PIT6457B, published January 12, 2026. Its provided evidence summary identifies U164F as one of the bulletin’s additional diagnostic trouble codes. The supplied excerpt also states that the bulletin was created December 12, 2025, had its labor time updated January 12, 2026, and had its DTC list updated. No further code-specific technical interpretation is established by the supplied verified evidence.

3. What system is affected?

Not yet established by verified evidence.

4. How serious is this code?

Unknown. The diagnostic record lists severity as unknown.

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?

Unknown. The supplied verified evidence does not establish whether it is safe to drive with U164F present.

8. Can I charge the vehicle?

Unknown. The supplied verified evidence does not establish whether it is safe to charge with U164F present.

9. What you can safely do

  • Record any warning messages and the conditions when U164F was retrieved.
  • Arrange diagnosis by a Cadillac service provider if the code is present.
  • Do not attempt high-voltage system repair based on this information; no high-voltage repair procedure is established by the supplied evidence.

10. Step-by-step troubleshooting

  1. Use Cadillac bulletin PIT6457B and applicable service information during professional diagnosis.
  2. No code-specific diagnostic steps are established by the supplied verified evidence.

11. When to contact service

Cadillac service should evaluate U164F using bulletin PIT6457B and applicable vehicle service information. Service urgency is not established by the supplied evidence.

12. What the service center may check

  • Confirm whether the vehicle is a 2023–2026 U.S.-market Cadillac CELESTIQ, LYRIQ, OPTIQ, or VISTIQ.
  • Review Cadillac bulletin PIT6457B, NHTSA manufacturer communication MC-11027686-0001.
  • No additional inspection, test, or repair checks are established by the supplied verified evidence.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Cadillac PIT6457B, NHTSA manufacturer communication MC-11027686-0001, published January 12, 2026. The supplied summary lists U164F among additional keywords/DTCs and notes bulletin updates to labor time and the DTC list.

16. Recall information

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

17. Official manufacturer information

Official source: NHTSA Manufacturer Communication PDF 11027686, Cadillac PIT6457B: https://static.nhtsa.gov/odi/tsbs/2026/MC-11027686-0001.pdf

19. Frequently asked questions

What does Cadillac U164F mean?

Not yet established by verified evidence. The supplied bulletin summary only confirms that U164F is listed in Cadillac bulletin PIT6457B.

Which vehicles are covered by the verified applicability data?

2023–2026 U.S. Cadillac CELESTIQ, LYRIQ, OPTIQ, and VISTIQ vehicles.

Can I drive or charge with U164F?

Not yet established by verified evidence. Driving and charging safety are both listed as unknown.

20. Sources & verification

Verified
Cadillac U164F: Created On 12/12/2025 - Updated Labor Time 01/12/2026… | EV Diagnostics