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Audi Child lock: fault

Child lock: fault

Common search variants: Child lock fault · Search ignores case and common separators.

DriveUnknown. The supplied diagnostic record does not establish whether driving is safe with this warning.
ChargeUnknown. The supplied diagnostic record does not establish whether charging is safe with this warning.
ServiceService need is listed as unknown in the diagnostic record. However, verified Audi manufacturer communications address this warning and DTC B177901; professional diagnosis is appropriate to confirm child-lock operation and investigate the electrical error.
Confidence90%

Quick answer

For a 2022 Audi Q4 e-tron in the US, the instrument-cluster warning “Child lock fault” is documented in Audi manufacturer communications with DTC B177901. The verified description for B177901 is “Function lighting child safety electrical error.”

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 Child lock: fault mean?

For a 2022 Audi Q4 e-tron in the US, the instrument-cluster warning “Child lock fault” is documented in Audi manufacturer communications with DTC B177901. The verified description for B177901 is “Function lighting child safety electrical error.”

2. Technical explanation

Verified manufacturer-communication evidence links the “Child lock fault” warning to DTC B177901. A later communication describes B177901 as “Function lighting child safety electrical error.” The supplied evidence does not establish the specific failed component, root cause, or repair procedure.

3. What system is affected?

Child-lock function / child-safety function lighting, based on the verified DTC description.

4. How serious is this code?

Unknown. The diagnostic record lists severity as unknown.

5. Symptoms you may notice

  • Instrument cluster displays the warning “Child lock fault.”
  • DTC B177901 may be stored: “Function lighting child safety electrical error.”

6. Possible causes

  • Not yet established by verified evidence. The verified material identifies an electrical error in the child-safety function lighting but does not identify a specific component or underlying cause.

7. Can I still drive the vehicle?

Unknown. The supplied diagnostic record does not establish whether driving is safe with this warning.

8. Can I charge the vehicle?

Unknown. The supplied diagnostic record does not establish whether charging is safe with this warning.

9. What you can safely do

  • Arrange diagnosis by an Audi service provider or qualified automotive technician.
  • Record the warning message and any diagnostic trouble codes present.
  • Do not assume that the child-lock function is operating normally until it has been inspected.

10. Step-by-step troubleshooting

  1. Have the vehicle scanned for DTC B177901.
  2. Use the applicable Audi manufacturer communication as a reference during diagnosis.
  3. Not yet established by verified evidence: additional owner-performed troubleshooting steps or component-level test procedures.

11. When to contact service

Service need is listed as unknown in the diagnostic record. However, verified Audi manufacturer communications address this warning and DTC B177901; professional diagnosis is appropriate to confirm child-lock operation and investigate the electrical error.

12. What the service center may check

  • Confirm the instrument-cluster “Child lock fault” warning.
  • Check for DTC B177901.
  • Reference Audi manufacturer communication A6424002074791_1 or revision A6424012074791_2, as applicable.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied source summaries do not provide a verified repair resolution.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Audi manufacturer communication A6424002074791_1, reported to NHTSA as Manufacturer Communication 11007242 and 11007323, published August 8, 2024. It addresses the instrument-cluster warning “Child lock fault” with DTC B177901.
  • Audi manufacturer communication A6424012074791_2, reported to NHTSA as Manufacturer Communication 11009942, published October 14, 2024. It addresses “Child lock fault” and DTC B177901, described as “Function lighting child safety electrical error.”

16. Recall information

  • No recall is established by the supplied verified evidence.

17. Official manufacturer information

Official NHTSA manufacturer-communication records: https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2020-2024.zip#nhtsa_id=11007242 ; https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2020-2024.zip#nhtsa_id=11009942

19. Frequently asked questions

What does “Child lock fault” mean on a 2022 Audi Q4 e-tron?

Verified Audi manufacturer-communication evidence associates the warning with DTC B177901. The later communication describes the DTC as “Function lighting child safety electrical error.”

Which vehicle is covered by the supplied applicability evidence?

The supplied applicability record identifies the 2022 Audi Q4 e-tron for the US market.

Can I drive with a “Child lock fault” warning?

Not yet established by verified evidence. The diagnostic record lists safe-to-drive status as unknown.

Is this warning related to charging or the high-voltage system?

Not yet established by verified evidence. The supplied material concerns the child-lock warning and child-safety function lighting electrical error; it does not establish a charging or high-voltage-system connection.

20. Sources & verification

Verified
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