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Cadillac U01B0

Lost Communication with Battery Monitor Module • U0284: Lost Communication with Active Grille Air Shutter 1 Motor Module • U0285: Lost Communication with Active Grille Air Shutter

DriveUnknown. The supplied verified evidence does not establish whether it is safe to drive with U01B0.
ChargeUnknown. The supplied verified evidence does not establish whether charging is safe or affected with U01B0.
ServiceService need is unknown in the supplied diagnostic record. A qualified Cadillac/GM service facility can evaluate U01B0 and any accompanying DTCs.
Confidence95%

Quick answer

For 2017–2018 Cadillac CT6 vehicles in the US, U01B0 is listed in GM/Cadillac service bulletin 15-NA-087 as “Lost Communication with Battery Monitor Module.” The supplied evidence does not establish whether the vehicle is safe to drive or charge, or identify a confirmed repair.

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 U01B0 mean?

For 2017–2018 Cadillac CT6 vehicles in the US, U01B0 is listed in GM/Cadillac service bulletin 15-NA-087 as “Lost Communication with Battery Monitor Module.” The supplied evidence does not establish whether the vehicle is safe to drive or charge, or identify a confirmed repair.

2. Technical explanation

The diagnostic record identifies U01B0 as a communication-related DTC for the Battery Monitor Module. The same verified NHTSA-published manufacturer communication (15-NA-087) lists U01B0 among multiple DTCs that a technician may observe with a scan tool. It also lists U0284 and U0285, which concern lost communication with Active Grille Air Shutter motor modules. The supplied evidence does not establish that all listed codes must occur together, nor does it establish a specific underlying fault for U01B0.

3. What system is affected?

Battery Monitor Module communication. The supplied bulletin evidence also references communication-related codes involving active grille air shutter motor modules, but does not establish that those systems are affected whenever U01B0 is present.

4. How serious is this code?

Unknown. Severity is not established by the supplied verified evidence.

5. Symptoms you may notice

  • A technician may observe U01B0 on a scan tool.
  • No driver-visible 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 establish whether it is safe to drive with U01B0.

8. Can I charge the vehicle?

Unknown. The supplied verified evidence does not establish whether charging is safe or affected with U01B0.

9. What you can safely do

  • Arrange diagnosis by a qualified Cadillac/GM service facility or other appropriately trained technician.
  • Do not attempt high-voltage or electrical-system repairs based on this code alone.

10. Step-by-step troubleshooting

  1. Have a qualified technician retrieve and assess all stored DTCs with a scan tool.
  2. Review GM/Cadillac manufacturer communication 15-NA-087 as applicable to the vehicle.
  3. Further diagnostic steps are not established by the supplied verified evidence.

11. When to contact service

Service need is unknown in the supplied diagnostic record. A qualified Cadillac/GM service facility can evaluate U01B0 and any accompanying DTCs.

12. What the service center may check

  • Scan for U01B0 and other stored DTCs. The supplied bulletin states that a technician may observe U01B0 on a scan tool.
  • Consider the other DTCs listed in bulletin 15-NA-087 when present: P15FF, P16DC, P305D, P305E, U0284, U0285, U1345, U135A, and U135E. The evidence does not establish that these codes are always present with U01B0.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM/Cadillac bulletin 15-NA-087, published by NHTSA as Manufacturer Communication PDF 10225708 on 2022-10-25, lists U01B0: Lost Communication with Battery Monitor Module among DTCs a technician may observe on a scan tool.
  • The supplied evidence does not provide the bulletin’s confirmed cause, repair procedure, or applicability details beyond the provided 2017–2018 Cadillac CT6 US fitment.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified source: NHTSA Manufacturer Communication PDF 10225708, GM/Cadillac bulletin 15-NA-087: https://static.nhtsa.gov/odi/tsbs/2022/MC-10225708-0001.pdf

19. Frequently asked questions

What does U01B0 mean on a Cadillac CT6?

For the supplied Cadillac record, U01B0 means “Lost Communication with Battery Monitor Module.”

Which vehicles are supported by the supplied evidence?

The supplied applicability evidence identifies US-market 2017–2018 Cadillac CT6 vehicles.

Are U0284 and U0285 the same as U01B0?

No. The supplied bulletin lists them separately. U0284 concerns lost communication with Active Grille Air Shutter 1 Motor Module, and U0285 concerns lost communication with Active Grille Air Shutter 2 Motor Module.

Does U01B0 confirm a specific failed part?

No. A specific cause or failed component is not established by the supplied verified evidence.

20. Sources & verification

ReferenceVerified
Cadillac U01B0: Lost Communication with Battery Monitor Module •… | EV Diagnostics