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Audi B1A8704

Function button charge door 2 faulty

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceAudi service is appropriate if B1A8704 is stored or the charging flap cannot be opened. The supplied official communications document this code in the OBC but do not establish urgency, drivability, or charging status.
Confidence95%

Quick answer

Audi DTC B1A8704 means “Function button charge door 2 faulty.” Verified Audi manufacturer communications list it for certain US-market 2020–2021 Audi e-tron vehicles.

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 B1A8704 mean?

Audi DTC B1A8704 means “Function button charge door 2 faulty.” Verified Audi manufacturer communications list it for certain US-market 2020–2021 Audi e-tron vehicles.

2. Technical explanation

Verified Audi communications identify B1A8704 as a fault stored in the high-voltage battery charger control module (OBC), J1050, address word 00C6. The verified wording is “Function button charge door 2 faulty.”

3. What system is affected?

Charge-door function button 2; the DTC is reported in the high-voltage battery charger control module (OBC), J1050 (address word 00C6).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • The charging flap cannot be opened.
  • A charging flap 1/2 defect is described in the referenced Audi communications.
  • The auxiliary heating may have been activated via the app but the vehicle was not pre-heated.

6. Possible causes

  • A fault identified by Audi as “Function button charge door 2 faulty.” Further root 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

  • If the charging flap cannot be opened, arrange diagnosis by an Audi service provider.
  • Do not attempt high-voltage system repair based on this code.

10. Step-by-step troubleshooting

  1. Have a qualified service provider scan the high-voltage battery charger control module (OBC), J1050, address word 00C6, for stored faults.
  2. Not yet established by verified evidence whether any owner-performed diagnostic or repair procedure applies.

11. When to contact service

Audi service is appropriate if B1A8704 is stored or the charging flap cannot be opened. The supplied official communications document this code in the OBC but do not establish urgency, drivability, or charging status.

12. What the service center may check

  • Confirm B1A8704 in high-voltage battery charger control module (OBC), J1050, address word 00C6.
  • Review any additional stored DTCs listed in the applicable Audi manufacturer communication.
  • Assess the reported charging-flap operation concern.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Audi manufacturer communication A9321422061788_1, published February 5, 2021; NHTSA document MC-10186996-0001.
  • Audi manufacturer communication A9321452061788_2, published March 29, 2021; NHTSA document MC-10189601-0001.
  • Audi manufacturer communication A9321472061788_3, published April 30, 2021; NHTSA document MC-10191572-0001.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified applicability: US-market Audi e-tron model years 2020–2021. Official source: NHTSA-hosted Audi manufacturer communications, including https://static.nhtsa.gov/odi/tsbs/2021/MC-10191572-0001.pdf

19. Frequently asked questions

What does Audi code B1A8704 mean?

It means “Function button charge door 2 faulty.”

Where is B1A8704 stored?

Audi communications list it in the high-voltage battery charger control module (OBC), J1050, address word 00C6.

Can B1A8704 prevent the charging flap from opening?

The referenced Audi communications describe a condition in which the charging flap cannot be opened and list B1A8704 among the possible stored DTCs. They do not establish that B1A8704 alone is the cause in every case.

Is it safe to drive or charge with B1A8704?

Not yet established by verified evidence.

20. Sources & verification

Verified
Audi B1A8704: Function button charge door 2 faulty | EV Diagnostics