EV Diagnostics
Verified EV diagnostic knowledge page

Dodge B1E21

Backup Battery Component Internal Failure

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService need is not explicitly established by the supplied evidence; however, professional diagnosis is appropriate because official Dodge manufacturer communications address B1E21-96.
Confidence95%

Quick answer

B1E21 means “Backup Battery Component Internal Failure.” Verified Dodge/NHTSA communications associate the code with a MIL and, in one communication, a Uconnect-box battery popup message.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

Video guides

Watch Videos

Relevant videos play here without leaving this diagnostic page.

No sufficiently relevant embeddable video has been accepted for this diagnostic yet.

Videos are supporting material and never override OEM or regulator evidence.

1. What does B1E21 mean?

B1E21 means “Backup Battery Component Internal Failure.” Verified Dodge/NHTSA communications associate the code with a MIL and, in one communication, a Uconnect-box battery popup message.

2. Technical explanation

The supplied verified evidence identifies B1E21-96 as “Backup Battery Component Internal Failure.” The evidence does not establish a root cause beyond that diagnostic description, nor does it provide a repair procedure in the supplied material.

3. What system is affected?

Backup battery component. The exact subsystem architecture is not yet established by verified evidence.

4. How serious is this code?

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

5. Symptoms you may notice

  • Malfunction Indicator Lamp (MIL) illumination may occur.
  • A popup message at the radio stating “Battery of Uconnect Box” is referenced in one official manufacturer communication; the complete message text is not present in the supplied evidence.

6. Possible causes

  • Backup Battery Component Internal Failure, as identified by DTC B1E21-96.
  • Further underlying causes are 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 an authorized Dodge service facility or qualified technician.
  • Record any MIL illumination and any radio/Uconnect popup message for the service visit.
  • Do not attempt high-voltage or battery-component repair based on this code alone.

10. Step-by-step troubleshooting

  1. Confirm the stored DTC and its suffix; the official communications specifically reference B1E21-96.
  2. Check for the associated MIL condition and any Uconnect-box battery popup message reported by the customer.
  3. Further diagnostic steps are not yet established by the supplied verified evidence.

11. When to contact service

Service need is not explicitly established by the supplied evidence; however, professional diagnosis is appropriate because official Dodge manufacturer communications address B1E21-96.

12. What the service center may check

  • Verify whether B1E21-96 is active.
  • Document MIL illumination, if present.
  • Document any radio popup referring to the Uconnect-box battery, if present.
  • Consult the applicable Dodge manufacturer communication for vehicle-specific service direction.

13. Possible repair or resolution

  • A specific repair resolution is not included in the supplied verified evidence.
  • Do not replace or repair components solely from this summary; follow the applicable official Dodge service communication.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication 11026660, reference 9100734, published December 10, 2025. It references active B1E21-96 and a reported radio popup message beginning “Battery of Uconnect Box.”
  • NHTSA Manufacturer Communication 11026677, bulletin 08-394-25 REV. A, published December 12, 2025. It states that a MIL may illuminate and B1E21-96 may set.
  • NHTSA Manufacturer Communication 11026549, bulletin 08-394-25, published December 5, 2025. It states that a MIL may illuminate and B1E21-96 may set.

16. Recall information

  • No recall information was supplied or established by verified evidence.

17. Official manufacturer information

Verified applicability: U.S.-market 2024–2026 Dodge Charger and 2024–2026 Dodge Hornet. Official NHTSA-hosted manufacturer communications: https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2025-2026.zip#nhtsa_id=11026660 ; https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2025-2026.zip#nhtsa_id=11026677 ; https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2025-2026.zip#nhtsa_id=11026549

19. Frequently asked questions

What does Dodge code B1E21 mean?

It means “Backup Battery Component Internal Failure.” The official communications specifically refer to B1E21-96.

Which vehicles are supported by the supplied evidence?

U.S.-market 2024–2026 Dodge Charger and 2024–2026 Dodge Hornet.

Can B1E21 turn on the check-engine light?

Yes. Two supplied official manufacturer communications state that the MIL may illuminate when B1E21-96 is present.

Can I continue driving or charging?

Not yet established by verified evidence.

Is there an official repair identified in the supplied evidence?

No specific repair procedure or resolution is included in the supplied evidence.

20. Sources & verification

Verified
Dodge B1E21: Backup Battery Component Internal Failure | EV Diagnostics