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Service bulletin PIT5774C

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10201330
Published by NHTSA2021-09-13
Manufacturer's numberPIT5774C
Manufacturer's date2021-08-26
NHTSA componentELECTRICAL SYSTEM

NHTSA's summary

This Preliminary information communicates an issue with: Overhead Console Inoperative / Service Safety Restraints Message / Sunroof Inoperative / DTC's B1A7A and U1121. Dealers are to cycle the power to the overhead console to correct the issue. Engineering has released updated roof consoles to correct this concern. Dealers are to replace the roof console.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Electrical system

Trouble codes named

B1A7A, U1121

Vehicles listed
CHEVROLET SUBURBAN2021
CHEVROLET TAHOE2021
GMC YUKON XL2021

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
21V4210002021-06-10. AIR BAGS:SRS MALFUNCTION WARNING LAMP/LIGHT; ELECTRICAL SYSTEM:SOFTWARE

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
23-NA-1702025-10-25. Service bulletin. This bulletin advises the tech to inspect deeper into what may be to main cause of an engine failure.
24-NA-2292025-06-03. Service bulletin. This bulletin provides a procedure on how to check for a battery drain utilizing the Picoscope and how to measure the load on the system that may be causing a drain.
25-NA-0872025-05-02. Service bulletin. This service bulletin provides information on the proper Reflective High Temperature Heat and/or Insulating Tape to use for certain repairs, such as Wiring Harness Repairs.
23-NA-1852025-04-28. Service bulletin. This service bulletin helps diagnose/reduce possible CCND issues on Transfer Cases - Service 4WD on DIC, Intermittent Failures, Noise Concerns, Driveline/Steering Vibration/Shudder, Intermittent DTCs/MIL Illuminated, Engagement/Disengagement/Ratcheting Concerns.
13-08-116-001K2025-04-25. Service bulletin. The intent of this service bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
24-NA-0982025-04-24. Service bulletin. This service bulletin provides information for dealers/technicians on Service Programming System (SPS) Error Codes E4398, E4399, E4401, E4403, M4404, M4413, M6954, M6955, E4414, E4423, E4491, E4492, or E6961 and resolution information.
15-06-03-001F2025-04-15. Service bulletin. This service bulletin provides information to diagnose batteries that have set for a long period of time and/or cold weather climates and testing those batteries.
PIE0820A2025-04-09. Service bulletin. This engineering information (EI) is requesting information from technicians to perform the check list provided and contact the engineer listed in regard to the power sliding console being inoperative.
25-NA-0322025-02-28. Service bulletin. This bulletin provides information to the tech on how to diagnosis the EGR system from possible issue that may cause the DTCs to set and cause the customers concern of a MIL Illuminated.
23-NA-0642025-02-12. Service bulletin. This service bulletin provides information on the Transport Mode Feature, also known as Logistics mode, which is used to increase the 12V Battery stand time of the vehicle during transit and or long period of stand time at the dealerships.