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Audi U112100

data bus, missing message

DriveNot yet established by verified evidence. If an air-suspension malfunction warning is present, arrange diagnosis by an Audi-qualified service provider.
ChargeNot yet established by verified evidence. U112100 is documented in high-voltage battery charger control module contexts, but the code alone does not prove that charging is unavailable or unsafe.
ServiceAudi-qualified service is recommended to identify the module context and apply the relevant factory diagnostic procedure. Immediate service urgency is not established by verified evidence.
Confidence95%

Quick answer

Audi DTC U112100 means “data bus, missing message.” Verified evidence links it to more than one system context, including adaptive air suspension and the high-voltage battery charger control module. The code alone does not establish a single failed part or whether the vehicle is safe to drive or charge.

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 U112100 mean?

Audi DTC U112100 means “data bus, missing message.” Verified evidence links it to more than one system context, including adaptive air suspension and the high-voltage battery charger control module. The code alone does not establish a single failed part or whether the vehicle is safe to drive or charge.

2. Technical explanation

U112100 is a communication-related DTC indicating a missing data-bus message. In an Audi air-suspension bulletin, it may be stored in the suspension control module with symptom code 262400 when an air-suspension malfunction warning is displayed. In separate Audi charging-system bulletins, it may be stored in high-voltage battery charger control module J1050 (address 00C6), including a documented diagnosis issue in software version 0079 that could store the DTC without cause. The installed control module, accompanying DTCs, warning messages, and vehicle configuration are necessary to determine the applicable diagnostic path.

3. What system is affected?

Not a single system is established. Verified contexts include the suspension control module/adaptive-suspension compressor communication and high-voltage battery charger control module J1050 (on-board charger).

4. How serious is this code?

Unknown. Verified evidence does not assign a severity level to U112100 by itself.

5. Symptoms you may notice

  • An air-suspension malfunction warning with an air-spring symbol in the instrument cluster is documented in one Audi bulletin context.
  • Charging-related concerns and failed app-activated auxiliary pre-heating are documented in separate high-voltage battery charger control module bulletin contexts.
  • Other symptoms are not yet established by verified evidence.

6. Possible causes

  • In the air-suspension bulletin context, Audi directs inspection for irregularities in wiring and connector contacts between the relevant suspension/compressor control modules.
  • For high-voltage battery charger control module J1050 software version 0079, Audi documents a diagnosis issue that could store U112100 without cause.
  • No universal component failure or root cause is established by verified evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence. If an air-suspension malfunction warning is present, arrange diagnosis by an Audi-qualified service provider.

8. Can I charge the vehicle?

Not yet established by verified evidence. U112100 is documented in high-voltage battery charger control module contexts, but the code alone does not prove that charging is unavailable or unsafe.

9. What you can safely do

  • Record all instrument-cluster warnings and the complete diagnostic scan, including the module that stored U112100 and any accompanying DTCs.
  • Use only normal owner-level vehicle controls; do not attempt high-voltage system repair.
  • Schedule diagnosis with an Audi-qualified service provider when the code is current, warning messages are present, or charging/pre-heating concerns occur.

10. Step-by-step troubleshooting

  1. Identify the control module that stored U112100.
  2. For the documented air-suspension context, inspect wiring and connector contacts between the relevant suspension/compressor control modules as specified by Audi service information.
  3. For the documented high-voltage battery charger control module context, check the applicable Audi software status and bulletin guidance.
  4. Further troubleshooting is not yet established by verified evidence.

11. When to contact service

Audi-qualified service is recommended to identify the module context and apply the relevant factory diagnostic procedure. Immediate service urgency is not established by verified evidence.

12. What the service center may check

  • Read all DTCs and identify whether U112100 is stored in the suspension control module or high-voltage battery charger control module J1050.
  • In the air-suspension context, check for irregularities in wiring and connector contacts between the suspension/compressor control modules.
  • In the J1050 charging-control context, verify whether the vehicle has the documented software version 0079 diagnosis issue and follow applicable Audi service guidance.

13. Possible repair or resolution

  • For the documented air-suspension context, Audi specifies checking wiring and connector contacts; a specific repair outcome is not established by the supplied evidence.
  • For the documented J1050 software context, revised software was stated to be in development so the DTC would no longer be stored without cause. The exact final repair or software version is not established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA manufacturer communication MC-10214467-0001 (Audi bulletin A4322622059363_3, published 2022-06-09): U112100 may be stored in the suspension control module with an air-suspension malfunction warning.
  • NHTSA manufacturer communication MC-10200437-0001 (Audi bulletin A4321532059363_2, published 2021-08-12): documents the same air-suspension context.
  • NHTSA manufacturer communication MC-10174551-0001 (Audi bulletin A4320342059363_1, published 2020-04-28): directs checks of wiring and connector contacts in the documented air-suspension communication context.
  • NHTSA manufacturer communication MC-10189600-0001 (Audi bulletin A9321442062631_1, published 2021-03-29): documents a J1050 software version 0079 diagnosis issue that can store U112100 without cause.
  • NHTSA manufacturer communications MC-10186996-0001, MC-10189601-0001, and MC-10191572-0001: document U112100 among DTCs in high-voltage battery charger control module contexts.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official NHTSA-hosted Audi manufacturer communications are listed above. Verified US applicability records include Audi A7 model years 2019–2023, A8 model years 2019–2023, Q5 model years 2019–2023, and e-tron model years 2019–2023. These applicability records do not establish that every vehicle in those ranges has the same repair or bulletin applicability.

19. Frequently asked questions

What does Audi U112100 mean?

It means “data bus, missing message.”

Does U112100 identify a failed part?

No. The supplied evidence documents different module contexts and does not establish one universal failed part.

Can U112100 be caused by software?

Yes, in one documented context: Audi reported a diagnosis issue in high-voltage battery charger control module J1050 software version 0079 that could store the DTC without cause.

Is U112100 related to air suspension?

It can be. Audi documents it in a suspension-control-module context with an air-suspension malfunction warning.

Is U112100 related to charging?

It can be. Audi documents it among DTCs stored in high-voltage battery charger control module J1050. Whether charging is affected in an individual vehicle is not established by the code alone.

20. Sources & verification

Verified
Audi U112100: data bus, missing message | EV Diagnostics