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Chevrolet B126B

Some customers may comment that Super Cruise is unavailable and there is a "Service Driver Assist" message displayed on the instrument cluster. Dealer technicians may find DTC B126

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact a Chevrolet dealer or qualified service facility for diagnosis of the Super Cruise / Service Driver Assist condition and B126B.
Confidence95%

Quick answer

For certain 2022 Chevrolet Bolt EUV vehicles in the US, DTC B126B has been documented with Super Cruise unavailable and a “Service Driver Assist” message. The bulletin identifies B126B as “Map Data Programming” in the Digital Map Control Module.

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 B126B mean?

For certain 2022 Chevrolet Bolt EUV vehicles in the US, DTC B126B has been documented with Super Cruise unavailable and a “Service Driver Assist” message. The bulletin identifies B126B as “Map Data Programming” in the Digital Map Control Module.

2. Technical explanation

Verified NHTSA-posted GM manufacturer communications 22-NA-124 describe a condition in which Super Cruise may be unavailable and “Service Driver Assist” may appear in the instrument cluster. Dealers may find B126B Map Data Programming current or stored in recent history in the K179 Digital Map Control Module / Digital Map Control Module.

3. What system is affected?

Super Cruise / driver-assistance functionality and the Digital Map Control Module (K179).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • Super Cruise may be unavailable.
  • A “Service Driver Assist” message may be displayed on the instrument cluster.
  • DTC B126B Map Data Programming may be current or stored in recent history in the Digital Map Control Module.

6. Possible causes

  • The supplied bulletin evidence identifies a map-data-programming condition associated with B126B. The full specific cause statement is not established by the supplied verified evidence excerpt.

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

  • Do not rely on Super Cruise while it is unavailable.
  • Arrange diagnosis by a Chevrolet dealer or qualified service facility if the message or DTC is present.

10. Step-by-step troubleshooting

  1. A dealer can check for B126B Map Data Programming in the K179 Digital Map Control Module, including current and recent-history status.
  2. The supplied evidence notes that some dealer technicians may be unsuccessful performing service update N222360520, “Outdated Map Data,” for inventory vehicles.

11. When to contact service

Contact a Chevrolet dealer or qualified service facility for diagnosis of the Super Cruise / Service Driver Assist condition and B126B.

12. What the service center may check

  • Check the Digital Map Control Module (K179) for current or recent-history DTC B126B Map Data Programming.
  • Review GM manufacturer communication 22-NA-124 and applicable vehicle service information.

13. Possible repair or resolution

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • GM manufacturer communication / bulletin 22-NA-124, posted by NHTSA as MC-10215630 (June 20, 2022) and MC-10232457 (February 24, 2023).
  • The supplied evidence references N222360520: Service Update – Outdated Map Data (Inventory Vehicles Only), dated May 11, 2022.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Official NHTSA-posted manufacturer communication: 22-NA-124. https://static.nhtsa.gov/odi/tsbs/2023/MC-10232457-0001.pdf

19. Frequently asked questions

What does B126B mean in this evidence?

It is identified as “B126B Map Data Programming” in the Digital Map Control Module.

Can B126B affect Super Cruise?

Yes. The supplied official bulletin evidence describes Super Cruise being unavailable, along with a possible “Service Driver Assist” cluster message, when B126B is found.

Does this evidence confirm that the vehicle is unsafe to drive?

No. Drive safety status is not established by the supplied verified evidence.

Does this evidence identify a recall?

No recall is established by the supplied verified evidence.

20. Sources & verification

Verified
Chevrolet B126B: Some customers may comment that Super Cruise is… | EV Diagnostics