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Cadillac U359E

voltage battery surge tank and document via photo. 3. Observe and record the Batte

DriveUnknown. The supplied verified evidence does not provide a driveability determination for U359E.
ChargeUnknown. The supplied verified evidence does not provide a charging determination for U359E.
ServiceContact a Cadillac/GM service facility or certified EV repair facility. Bulletin 23-NA-151 states that its procedures are intended for professional technicians, not do-it-yourself repair, and require specified training, tools, and equipment.
Confidence95%

Quick answer

U359E is listed in GM bulletin 23-NA-151 for certain Cadillac EVs. The supplied verified evidence does not establish a complete diagnostic definition for this code, despite the truncated database title/meaning.

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 U359E mean?

U359E is listed in GM bulletin 23-NA-151 for certain Cadillac EVs. The supplied verified evidence does not establish a complete diagnostic definition for this code, despite the truncated database title/meaning.

2. Technical explanation

For the covered vehicles, bulletin 23-NA-151 includes U359E among DTCs that can trigger a professional diagnostic process. The bulletin evidence directs trained technicians to verify whether listed DTCs are current or history, document the customer concern, visually inspect and photograph coolant level in the high-voltage battery surge tank, and record battery-related information. The supplied evidence does not establish the precise subsystem fault definition of U359E.

3. What system is affected?

Not yet established by verified evidence. The bulletin workflow references the high-voltage battery surge tank and battery-related data, but this alone does not establish the exact affected system for U359E.

4. How serious is this code?

Unknown. No verified severity classification was supplied.

5. Symptoms you may notice

  • The bulletin asks technicians to document the customer concern and asks whether the vehicle was towed because of a no-start concern. This does not establish that a no-start or towing event occurs in every U359E case.
  • No other symptoms are established by the supplied 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 provide a driveability determination for U359E.

8. Can I charge the vehicle?

Unknown. The supplied verified evidence does not provide a charging determination for U359E.

9. What you can safely do

  • Arrange diagnosis by a Cadillac/GM service facility or another certified repair facility with the required EV training, tools, and equipment.
  • Provide the service facility with the stored DTC information and a clear description of the concern, including whether a no-start condition or tow occurred.
  • Do not attempt high-voltage battery diagnosis or repair yourself.

10. Step-by-step troubleshooting

  1. A qualified technician can determine whether U359E is current or history, as directed in bulletin 23-NA-151.
  2. The bulletin workflow includes documenting the customer concern.
  3. The bulletin workflow includes visual inspection and photographic documentation of coolant level in the high-voltage battery surge tank.
  4. The bulletin workflow includes recording battery-related information. Further specific diagnostic steps are not established by the supplied excerpts.

11. When to contact service

Contact a Cadillac/GM service facility or certified EV repair facility. Bulletin 23-NA-151 states that its procedures are intended for professional technicians, not do-it-yourself repair, and require specified training, tools, and equipment.

12. What the service center may check

  • Verify whether U359E is current or history, where applicable under the bulletin revision.
  • Obtain and document a clear description of the customer concern, including whether the vehicle was towed because of a no-start concern.
  • Visually inspect and document the coolant level in the high-voltage battery surge tank, including a photo.
  • Observe and record battery-related information as directed by the applicable bulletin revision.
  • Use the applicable GM service information and bulletin procedure; the supplied excerpts do not establish all subsequent checks.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied bulletin excerpts establish a professional diagnostic workflow but do not provide a verified final repair for every U359E occurrence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM/Cadillac bulletin 23-NA-151 is documented through NHTSA manufacturer communications, including MC-10243714 (September 5, 2023), MC-10245234 (October 19, 2023), MC-11011944 (November 20, 2024), MC-11012693 (December 11, 2024), and MC-11017886 (April 9, 2025).
  • The supplied evidence lists U359E in bulletin 23-NA-151 and states the bulletin is for professional technicians with required EV training, tools, and equipment.

16. Recall information

  • No recall is established by the supplied verified evidence.

17. Official manufacturer information

Official source: NHTSA-hosted GM manufacturer communication bulletin 23-NA-151, including https://static.nhtsa.gov/odi/tsbs/2025/MC-11017886-0001.pdf . Applicability in the supplied database: US-market Cadillac LYRIQ model years 2023–2026 and Cadillac VISTIQ model years 2023–2026. Verify applicability by VIN and the latest bulletin revision with Cadillac/GM.

19. Frequently asked questions

What does U359E mean?

Not yet established by verified evidence. The supplied database title and meaning are truncated and do not provide a reliable full definition.

Is U359E covered by a service bulletin?

Yes. U359E is listed in GM bulletin 23-NA-151 in the supplied NHTSA manufacturer-communication evidence.

Can I drive or charge with U359E?

Not yet established by verified evidence. No drive or charging determination was supplied.

Can I repair this myself?

No. The supplied bulletin states that the work is intended for professional technicians and requires specific training, tools, and equipment.

20. Sources & verification

Verified
Cadillac U359E: voltage battery surge tank and document via photo. 3.… | EV Diagnostics