EV Diagnostics
Verified EV diagnostic knowledge page

Jeep B166E

13 B17AD-13 May Be Set

DriveUnknown. The supplied verified evidence does not establish whether the vehicle is safe to drive with B166E-13 present.
ChargeUnknown. The supplied verified evidence does not establish whether charging is affected or whether the vehicle is safe to charge.
ServiceContact an authorized Jeep dealer or qualified service provider, particularly if trailer tow lights are inoperative or B166E-13 is stored.
Confidence95%

Quick answer

Jeep DTC B166E is documented in an official manufacturer communication for trailer tow lights being inoperative. That communication states B166E-13 and B17AD-13 may be set.

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 B166E mean?

Jeep DTC B166E is documented in an official manufacturer communication for trailer tow lights being inoperative. That communication states B166E-13 and B17AD-13 may be set.

2. Technical explanation

Verified evidence identifies this as: “B166E — 13 B17AD-13 May Be Set.” The associated official manufacturer communication is titled “Trailer Tow Lights Inoperative” and states that DTCs B166E-13 and B17AD-13 may be set. The supplied evidence does not establish a component-level fault cause, diagnostic procedure, or repair.

3. What system is affected?

Trailer tow lighting, based on the title of the official manufacturer communication.

4. How serious is this code?

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

5. Symptoms you may notice

  • Trailer tow lights inoperative.

6. Possible causes

  • Not yet established by verified evidence.

7. Can I still drive the vehicle?

Unknown. The supplied verified evidence does not establish whether the vehicle is safe to drive with B166E-13 present.

8. Can I charge the vehicle?

Unknown. The supplied verified evidence does not establish whether charging is affected or whether the vehicle is safe to charge.

9. What you can safely do

  • If trailer lighting is inoperative, do not rely on the trailer lamps for required road lighting or signaling.
  • Arrange diagnosis by an authorized Jeep service provider or qualified technician.
  • Do not attempt high-voltage or other hazardous vehicle repairs based on this information.

10. Step-by-step troubleshooting

  1. Confirm the stored DTC exactly, including the -13 suffix.
  2. Document whether trailer tow lights are inoperative.
  3. Have a qualified technician consult the applicable Jeep manufacturer communication and vehicle service information. Further diagnostic steps are not established by the supplied verified evidence.

11. When to contact service

Contact an authorized Jeep dealer or qualified service provider, particularly if trailer tow lights are inoperative or B166E-13 is stored.

12. What the service center may check

  • Verify the presence of B166E-13 and B17AD-13, if applicable.
  • Review Jeep manufacturer communication S2523000023, titled “Trailer Tow Lights Inoperative.”
  • Further service checks are not yet established by verified evidence.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication 11016708: S2523000023 — “Trailer Tow Lights Inoperative. Diagnostic Trouble Codes (DTCs) B166E-13 B17AD-13 May Be Set.” Published April 4, 2025.

16. Recall information

  • No recall information was supplied in the verified evidence.

17. Official manufacturer information

Official source: NHTSA Manufacturer Communication 11016708, Jeep communication S2523000023, published April 4, 2025. https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2025-2026.zip#nhtsa_id=11016708

19. Frequently asked questions

What does Jeep code B166E mean?

The supplied verified evidence describes it as “B166E — 13 B17AD-13 May Be Set” and associates B166E-13 with a manufacturer communication titled “Trailer Tow Lights Inoperative.”

What vehicles may be affected?

The supplied applicability evidence covers US-market 2022–2025 Jeep Grand Cherokee and 2022–2025 Jeep Wagoneer vehicles.

Can I drive with B166E-13?

Not yet established by verified evidence. However, trailer lighting should not be relied upon if it is inoperative.

Is B17AD-13 related?

Yes. The official manufacturer communication states that B166E-13 and B17AD-13 may be set.

20. Sources & verification

Verified
Jeep B166E: 13 B17AD-13 May Be Set | EV Diagnostics