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Cadillac U0235

- Do not replace the front camera. - Diagnose the CAN Bus 8 issue using SI 5199684. - If a module

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService diagnosis is appropriate because the verified Cadillac communication directs a CAN Bus 8 diagnostic procedure when the entire bus is affected. Driveability, charging status, and urgency are not established by the supplied evidence.
Confidence95%

Quick answer

For certain 2024–2026 Cadillac CELESTIQ, LYRIQ, OPTIQ, and VISTIQ vehicles in the U.S., U0235 appears in Cadillac’s PIT6503-series manufacturer communications as a loss-of-communication DTC that may be present with other CAN Bus 8 communication codes. If the entire CAN Bus 8 is affected, Cadillac directs technicians not to replace the B174W Front View Camera module and to diagnose CAN Bus 8 using SI 5199684.

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 U0235 mean?

For certain 2024–2026 Cadillac CELESTIQ, LYRIQ, OPTIQ, and VISTIQ vehicles in the U.S., U0235 appears in Cadillac’s PIT6503-series manufacturer communications as a loss-of-communication DTC that may be present with other CAN Bus 8 communication codes. If the entire CAN Bus 8 is affected, Cadillac directs technicians not to replace the B174W Front View Camera module and to diagnose CAN Bus 8 using SI 5199684.

2. Technical explanation

Verified manufacturer communication evidence identifies U0235 as an example of a loss-of-communication DTC that the K56 Serial Data Gateway Module may set against ECUs on CAN Bus 8. The cited communications instruct technicians to determine whether the K56 module is also setting loss-of-communication DTCs for other ECUs on CAN Bus 8. When the entire bus is impacted, the specified diagnostic path is SI 5199684; the front camera is not to be replaced on that basis.

3. What system is affected?

CAN Bus 8 communication network; the evidence also references the K56 Serial Data Gateway Module and B174W Front View Camera module.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • A stored U0235 DTC.
  • The K56 Serial Data Gateway Module may also set loss-of-communication DTCs against other ECUs on CAN Bus 8.
  • Additional driver-visible symptoms are not yet established by verified evidence.

6. Possible causes

  • An issue affecting the entire CAN Bus 8 is identified in the manufacturer communication as the condition requiring diagnosis through SI 5199684.
  • The specific underlying fault, component-level cause, and failure mode are not yet established by the supplied 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

  • Arrange diagnosis by a Cadillac/GM-qualified service facility.
  • Provide the service facility with DTC U0235 and any additional stored communication codes.
  • Do not assume the B174W Front View Camera module requires replacement solely because U0235 is present when the entire CAN Bus 8 is affected.

10. Step-by-step troubleshooting

  1. A qualified technician should determine whether the K56 Serial Data Gateway Module is also setting loss-of-communication DTCs against other ECUs on CAN Bus 8.
  2. If the entire CAN Bus 8 is impacted, Cadillac directs diagnosis using SI 5199684.
  3. Further consumer-performed troubleshooting is not established by verified evidence.

11. When to contact service

Service diagnosis is appropriate because the verified Cadillac communication directs a CAN Bus 8 diagnostic procedure when the entire bus is affected. Driveability, charging status, and urgency are not established by the supplied evidence.

12. What the service center may check

  • Check whether K56 Serial Data Gateway Module has loss-of-communication DTCs for other ECUs on CAN Bus 8.
  • Determine whether the entire CAN Bus 8 is impacted.
  • If the entire bus is impacted, diagnose CAN Bus 8 using SI 5199684.

13. Possible repair or resolution

  • Do not replace the B174W Front View Camera module when the entire CAN Bus 8 is impacted, according to the cited Cadillac communication.
  • The ultimate repair depends on the results of the SI 5199684 CAN Bus 8 diagnosis and is not further established by the supplied evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Cadillac PIT6503C, NHTSA Manufacturer Communication 11036219, published August 12, 2026: addresses CAN Bus 8 loss-of-communication DTCs including U0235; directs CAN Bus 8 diagnosis using SI 5199684 when the entire bus is impacted and says not to replace the B174W Front View Camera module in that condition. https://static.nhtsa.gov/odi/tsbs/2026/MC-11036219-0001.pdf
  • Cadillac PIT6503B, NHTSA Manufacturer Communication 11034014, published June 17, 2026. https://static.nhtsa.gov/odi/tsbs/2026/MC-11034014-0001.pdf
  • Cadillac PIT6503A, NHTSA Manufacturer Communication 11033726, published June 3, 2026. https://static.nhtsa.gov/odi/tsbs/2026/MC-11033726-0001.pdf
  • Cadillac PIT6503, NHTSA Manufacturer Communication 11031514, published April 14, 2026. https://static.nhtsa.gov/odi/tsbs/2026/MC-11031514-0001.pdf

16. Recall information

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

17. Official manufacturer information

The supplied official evidence consists of NHTSA-hosted Cadillac manufacturer communications in the PIT6503 series. They apply to specified U.S. Cadillac vehicles and discuss CAN Bus 8 communication diagnosis involving U0235.

19. Frequently asked questions

What does the verified evidence say about U0235?

It identifies U0235 as an example of a loss-of-communication DTC that may be set by the K56 Serial Data Gateway Module against ECUs on CAN Bus 8.

Should the front camera be replaced for this condition?

If the entire CAN Bus 8 is impacted, Cadillac’s communication says not to replace the B174W Front View Camera module.

What diagnostic procedure does Cadillac specify?

For an entire CAN Bus 8 impact, the communication directs diagnosis using SI 5199684.

Which vehicles are covered by the supplied evidence?

U.S. 2024–2026 Cadillac CELESTIQ, LYRIQ, OPTIQ, and VISTIQ are listed. LYRIQ is also separately listed for 2024–2025.

Is it safe to drive or charge with U0235?

Not yet established by verified evidence.

20. Sources & verification

ReferenceVerified
Cadillac U0235: - Do not replace the front camera. - Diagnose the CAN… | EV Diagnostics