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Cadillac U0131

to-Bumper coverage (Canada Base Warranty coverage), use the following labor operation. Reference the Applicable Warrantie

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a Cadillac/GM service facility for professional network diagnosis. The supplied evidence directs diagnosis of CAN Bus 2 in the documented multi-module communication-loss condition.
Confidence95%

Quick answer

For applicable Cadillac vehicles, U0131 is documented in official manufacturer communications as a loss-of-communication DTC that can occur with other CAN Bus 2 communication codes. The supplied diagnostic title/meaning is not a usable technical definition. A verified diagnosis requires checking whether multiple ECUs are affected; do not assume a component needs replacement.

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 U0131 mean?

For applicable Cadillac vehicles, U0131 is documented in official manufacturer communications as a loss-of-communication DTC that can occur with other CAN Bus 2 communication codes. The supplied diagnostic title/meaning is not a usable technical definition. A verified diagnosis requires checking whether multiple ECUs are affected; do not assume a component needs replacement.

2. Technical explanation

Official Cadillac communications PIT6503 through PIT6503C identify U0131 as an example of a loss-of-communication DTC that may be set by the K56 Serial Data Gateway Module along with other ECU communication codes on CAN Bus 2. When the entire bus is affected by multiple communication-loss DTCs, the bulletin directs technicians to diagnose CAN Bus 2 and not replace the B174W Front View Camera module. A separate 2023 communication, PIC6500A, lists U0131 symptom 00 among DTCs for which the controller should not be replaced; it instructs technicians to verify the customer concern and wait for an engineering resolution. The exact module represented by U0131, its standalone definition, and a confirmed root cause are not yet established by the supplied verified evidence.

3. What system is affected?

CAN Bus 2 serial communications, including the K56 Serial Data Gateway Module context described in PIT6503-series communications. A specific failed component is not yet established by verified evidence.

4. How serious is this code?

Unknown. The supplied verified evidence does not assign a severity level.

5. Symptoms you may notice

  • U0131 may be stored with other loss-of-communication DTCs on CAN Bus 2.
  • Multiple ECUs may have communication-loss DTCs when the entire CAN Bus 2 network is affected.
  • Additional driver-visible symptoms are not yet established by verified evidence.

6. Possible causes

  • A CAN Bus 2-wide communication issue is a documented diagnostic context when multiple ECUs have communication-loss DTCs.
  • A specific underlying cause is not yet established by 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 if U0131 is present, especially if multiple communication DTCs are stored.
  • Provide the service facility with all stored DTCs and any observed customer concern.
  • Do not authorize replacement of the B174W Front View Camera module solely because U0131 is present in the CAN Bus 2-wide condition described by PIT6503-series communications.

10. Step-by-step troubleshooting

  1. Check whether the K56 Serial Data Gateway Module is also reporting communication-loss DTCs against other ECUs on CAN Bus 2, as directed in PIT6503-series communications.
  2. If multiple ECUs show communication loss and the entire bus is affected, diagnose CAN Bus 2 rather than replacing the B174W Front View Camera module.
  3. For the PIC6500A condition, verify the customer concern. If U0131 symptom 00 is among the listed DTCs, do not replace the controller; the communication states to wait until engineering provides a resolution.
  4. If the PIC6500A-listed DTCs are not setting, follow normal SI diagnostics, as stated in that communication.

11. When to contact service

Contact a Cadillac/GM service facility for professional network diagnosis. The supplied evidence directs diagnosis of CAN Bus 2 in the documented multi-module communication-loss condition.

12. What the service center may check

  • Retrieve all diagnostic trouble codes from affected modules.
  • Determine whether multiple ECUs have loss-of-communication DTCs on CAN Bus 2.
  • Check whether the K56 Serial Data Gateway Module is setting related communication DTCs.
  • For the documented bus-wide condition, perform CAN Bus 2 diagnosis rather than replacing the front camera module.

13. Possible repair or resolution

  • Do not replace the B174W Front View Camera module when the entire CAN Bus 2 network is affected by multiple communication-loss DTCs, according to PIT6503-series communications.
  • Do not replace the controller for the PIC6500A-listed DTC condition, including U0131 symptom 00; that communication instructs technicians to await an engineering resolution.
  • A final confirmed repair is not yet established by the supplied verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • PIT6503C, NHTSA Manufacturer Communication 11036219, published August 12, 2026: U0131 is listed as an example of a CAN Bus 2 communication-loss DTC; diagnose CAN Bus 2 when multiple ECUs are affected and do not replace the B174W Front View Camera module.
  • PIT6503B, NHTSA Manufacturer Communication 11034014, published June 17, 2026: same documented CAN Bus 2 diagnostic context for U0131.
  • PIT6503A, NHTSA Manufacturer Communication 11033726, published June 3, 2026: same documented CAN Bus 2 diagnostic context for U0131.
  • PIT6503, NHTSA Manufacturer Communication 11031514, published April 14, 2026: same documented CAN Bus 2 diagnostic context for U0131.
  • PIC6500A, NHTSA Manufacturer Communication 10237683, published May 24, 2023: lists U0131 symptom 00 among DTCs for which the controller should not be replaced; verify the concern and await an engineering resolution.

16. Recall information

  • No recall information was supplied in the verified evidence.

17. Official manufacturer information

Official NHTSA-hosted manufacturer communications supplied: PIT6503C (https://static.nhtsa.gov/odi/tsbs/2026/MC-11036219-0001.pdf), PIT6503B (https://static.nhtsa.gov/odi/tsbs/2026/MC-11034014-0001.pdf), PIT6503A (https://static.nhtsa.gov/odi/tsbs/2026/MC-11033726-0001.pdf), PIT6503 (https://static.nhtsa.gov/odi/tsbs/2026/MC-11031514-0001.pdf), and PIC6500A (https://static.nhtsa.gov/odi/tsbs/2023/MC-10237683-9999.pdf). Supplied applicability: US-market Cadillac CELESTIQ 2024–2026, LYRIQ 2023–2026, OPTIQ 2024–2026, and VISTIQ 2024–2026; individual bulletin applicability should be confirmed by the service facility.

19. Frequently asked questions

What does U0131 mean on the applicable Cadillac vehicles?

The supplied canonical meaning is not a usable technical definition. Verified manufacturer communications identify U0131 as an example of a loss-of-communication DTC in a CAN Bus 2 diagnostic context. The exact module-specific definition is not yet established by the supplied evidence.

Does U0131 mean the front camera must be replaced?

No. In the documented condition where multiple ECUs have communication-loss DTCs and the entire CAN Bus 2 network is affected, PIT6503-series communications specifically say not to replace the B174W Front View Camera module.

Can U0131 occur with other codes?

Yes. PIT6503-series communications give U1611, U1643, U1610, and U1615 as examples that may accompany U0131 in the described CAN Bus 2 communication-loss condition.

Is there a confirmed repair for U0131?

Not from the supplied evidence. The bulletins direct network diagnosis in the multiple-module CAN Bus 2 condition and, for the PIC6500A-listed condition, instruct technicians not to replace the controller while awaiting an engineering resolution.

20. Sources & verification

ReferenceVerified
Cadillac U0131: to-Bumper coverage (Canada Base Warranty coverage),… | EV Diagnostics