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Chevrolet U164B

If customer concern is related to one of the symptoms below, verify customers radio is

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact an authorized Chevrolet/GM service facility for diagnosis when U164B is stored with a radio or infotainment concern. Ask the facility to review the applicable PIT6393 communication.
Confidence95%

Quick answer

For applicable Chevrolet vehicles, U164B is listed in GM/NHTSA manufacturer communications as a radio-related DTC that may set because of a software anomaly. The bulletin direction is to ignore this DTC in the specified context and not replace the radio solely for U164B.

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 U164B mean?

For applicable Chevrolet vehicles, U164B is listed in GM/NHTSA manufacturer communications as a radio-related DTC that may set because of a software anomaly. The bulletin direction is to ignore this DTC in the specified context and not replace the radio solely for U164B.

2. Technical explanation

Verified NHTSA-hosted GM manufacturer communications (PIT6393 revisions C through J) list U164B with B1596.86, U0142, U0265, U1615, and U164E. These communications state that the listed DTCs can set due to a software anomaly and instruct technicians not to replace the radio for these DTCs. The supplied canonical title is incomplete and does not establish a full code definition beyond its radio-related bulletin context.

3. What system is affected?

Radio / infotainment system context is established by the manufacturer communications. No broader vehicle-system diagnosis is established by the supplied evidence.

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

  • A radio software anomaly is established by the cited manufacturer communications as a reason U164B may set in the specified bulletin context.

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 with an authorized Chevrolet/GM service facility if there is a related radio or infotainment concern.
  • Provide the service facility with the stored DTC and the applicable manufacturer communication reference.
  • Do not authorize radio replacement solely because U164B is present; the cited bulletin specifically says not to replace the radio for this DTC in its stated context.

10. Step-by-step troubleshooting

  1. A qualified technician should follow the applicable GM manufacturer communication and verify the customer concern in the radio/infotainment context.
  2. The cited communications direct technicians to ignore U164B when it is among the listed DTCs setting due to the documented software anomaly.
  3. Radio software-update procedures, if applicable, should be performed by trained personnel using the manufacturer procedure. The bulletin cautions that USB file-transfer updates require the specified USB file handling.

11. When to contact service

Contact an authorized Chevrolet/GM service facility for diagnosis when U164B is stored with a radio or infotainment concern. Ask the facility to review the applicable PIT6393 communication.

12. What the service center may check

  • Confirm vehicle applicability and the exact stored DTCs.
  • Review the radio/infotainment customer concern.
  • Review the applicable GM PIT6393 revision and perform the manufacturer-directed process.
  • Determine whether a radio software update is applicable under the manufacturer procedure.

13. Possible repair or resolution

  • The verified bulletin direction is not to replace the radio solely for U164B when it is setting because of the identified software anomaly.
  • A specific final repair outcome is not otherwise established by the supplied evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM PIT6393J, NHTSA Manufacturer Communication 11029962, published March 6, 2026: lists U164B among radio-related DTCs that may set due to a software anomaly; directs technicians not to replace the radio for these DTCs.
  • GM PIT6457B, NHTSA Manufacturer Communication 11027686, published January 12, 2026: identifies U164B among radio-related DTC keywords. Full applicability and procedures are not established by the supplied excerpt.
  • GM PIT6393H, NHTSA Manufacturer Communication 11026861, published December 23, 2025: lists U164B among DTCs that may set due to a software anomaly; directs technicians not to replace the radio for these DTCs.
  • GM PIT6393F, NHTSA Manufacturer Communication 11024704, published October 23, 2025: lists U164B among DTCs that may set due to a software anomaly; directs technicians not to replace the radio for these DTCs.
  • GM PIT6393E, NHTSA Manufacturer Communication 11024438, published October 4, 2025: lists U164B among DTCs that may set due to a software anomaly; directs technicians not to replace the radio for these DTCs.
  • GM PIT6393D, NHTSA Manufacturer Communication 11023907, published October 1, 2025: lists U164B among DTCs that may set due to a software anomaly; directs technicians not to replace the radio for these DTCs.
  • GM PIT6393C, NHTSA Manufacturer Communication 11023342, published September 15, 2025: lists U164B among DTCs that may set due to a software anomaly; directs technicians not to replace the radio for these DTCs.

16. Recall information

No recall relationship is established by verified evidence.

17. Official manufacturer information

Official NHTSA-hosted manufacturer communication: PIT6393J, https://static.nhtsa.gov/odi/tsbs/2026/MC-11029962-0001.pdf

19. Frequently asked questions

What does Chevrolet U164B mean?

The supplied evidence establishes that U164B is addressed in GM radio-related manufacturer communications. It may set due to a documented software anomaly in the bulletin context. A complete standalone code definition is not yet established by verified evidence.

Should the radio be replaced for U164B?

No, not solely because U164B is present in the bulletin context. PIT6393 revisions state not to replace the radio for the listed DTCs, including U164B, because they may set due to a software anomaly.

Is U164B safe to drive with?

Not yet established by verified evidence.

Does U164B affect EV charging?

Not yet established by verified evidence.

Which vehicles are listed as applicable?

The supplied applicability data lists U.S. Chevrolet Blazer, Bolt EUV, Bolt EV, and Equinox vehicles for specified 2023–2026 model-year ranges. Exact bulletin applicability should be confirmed by a Chevrolet/GM service facility.

20. Sources & verification

Verified
Chevrolet U164B: If customer concern is related to one of the symptoms… | EV Diagnostics