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Audi U153E00

Emergency call module and communication unit Recognition in mobile communications network not possible

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact an Audi dealer or qualified Audi service provider for diagnosis of the SOS/telematics system. Audi’s bulletin includes specific diagnostic and replacement eligibility criteria.
Confidence95%

Quick answer

U153E00 indicates that the emergency-call module/communication unit could not be recognized on the mobile communications network. Audi documentation associates it with an SOS emergency-call-function-deactivated message and a loss of connection to the mobile network operator (AT&T).

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 U153E00 mean?

U153E00 indicates that the emergency-call module/communication unit could not be recognized on the mobile communications network. Audi documentation associates it with an SOS emergency-call-function-deactivated message and a loss of connection to the mobile network operator (AT&T).

2. Technical explanation

Audi identifies U153E00 as: “Emergency call module and communication unit Recognition in mobile communications network not possible.” In Audi Technical Service Bulletin 2055945 evidence, the DTC is stored in the telematics control module (ConBox High), J949, address word 0075. The bulletin states that this DTC can set when the vehicle loses signal to the mobile network operator, AT&T. Depending on how long the signal is lost, a full vehicle sleep cycle may be required for the DTC to become sporadic and permit the warning to clear. Audi also states that hardware or software malfunction of the control module is another scenario involving the SOS warning; the supplied evidence does not establish that every U153E00 event is caused by a module fault.

3. What system is affected?

Emergency-call/telematics system: telematics control module (ConBox High), J949, address word 0075, and its mobile-network connection.

4. How serious is this code?

Not yet established by verified evidence. The verified information establishes possible loss or deactivation of the SOS emergency-call function, but does not provide a driving-risk classification.

5. Symptoms you may notice

  • An SOS emergency-call-function-deactivated message may be displayed in the instrument cluster.
  • DTC U153E00 may be stored in the telematics control module.
  • The vehicle may have lost connection to the mobile network operator (AT&T).

6. Possible causes

  • Loss of signal/connection to the mobile network operator (AT&T).
  • Hardware or software malfunction of the telematics control module is identified by Audi as a scenario related to the SOS warning; it is not established as the cause of every U153E00 event.

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 an Audi service provider, particularly if the SOS emergency-call-function-deactivated message remains displayed.
  • Do not rely on the vehicle SOS emergency-call function while the message is present; the verified evidence indicates the function may be deactivated.
  • Do not attempt telematics-module or electrical-system repairs yourself.

10. Step-by-step troubleshooting

  1. A service provider can read the telematics control module, J949 (address word 0075), and evaluate U153E00.
  2. Audi states that, after a loss of mobile-network signal, a full vehicle sleep cycle may be needed for U153E00 to change to sporadic.
  3. Audi documentation notes that in some cases DTCs must be cleared after the sleep cycle/battery reset for the SOS warning message to disappear. This is a service procedure, not a guarantee of repair.

11. When to contact service

Contact an Audi dealer or qualified Audi service provider for diagnosis of the SOS/telematics system. Audi’s bulletin includes specific diagnostic and replacement eligibility criteria.

12. What the service center may check

  • Confirm U153E00 in telematics control module J949, address word 0075.
  • Review the DTC frequency counter.
  • Apply Audi’s documented diagnostic process, including consideration of a full sleep cycle after loss of mobile-network signal.
  • If module replacement is considered under Audi TSB 2055945, verify whether the U153E00 frequency counter is greater than 5.

13. Possible repair or resolution

  • Audi states that the ConBox High may only be replaced when U153E00 has a frequency counter greater than 5.
  • When replacement is eligible under the bulletin, Audi specifies telematics control module part number 992 035 286 C, regardless of the originally installed part listed in ETKA.
  • Audi states that replacing the ConBox with the originally installed part number will not permanently fix the customer concern.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Audi TSB 2055945, titled “SOS Emergency call function deactivated message in the cluster, DTC U153E00 stored in the telematics module.” NHTSA-hosted manufacturer communication: https://static.nhtsa.gov/odi/tsbs/2022/MC-10211914-0001.pdf
  • Audi TSB 2056076 references TSB 2055945 as potentially necessary to complete its procedure. NHTSA-hosted manufacturer communication: https://static.nhtsa.gov/odi/tsbs/2022/MC-10217910-0001.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified official manufacturer communications are published through NHTSA, including Audi TSB 2055945: https://static.nhtsa.gov/odi/tsbs/2022/MC-10211914-0001.pdf

19. Frequently asked questions

What does Audi code U153E00 mean?

It means the emergency call module and communication unit cannot be recognized in the mobile communications network.

Can U153E00 cause an SOS warning?

Yes. Audi TSB 2055945 associates U153E00 in the telematics module with an SOS emergency-call-function-deactivated message in the instrument cluster.

Does U153E00 always mean the telematics module must be replaced?

No. Audi states replacement of the ConBox High is permitted only when the U153E00 frequency counter is greater than 5. Signal loss to the mobile network operator is also identified in the bulletin.

Will the warning clear by itself?

Audi states that after mobile-network signal loss, a full vehicle sleep cycle may be required for the DTC to become sporadic. In some cases, Audi notes that DTCs must then be cleared for the cluster warning to disappear.

20. Sources & verification

Verified
Audi U153E00: Emergency call module and communication unit Recognition… | EV Diagnostics