# Service bulletin 21NA127

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.

- Type: Service bulletin
- NHTSA id: 10214208
- Published by NHTSA: 2022\-06\-21
- Manufacturer's number: 21NA127
- Manufacturer's date: 2022\-01\-21
- NHTSA component: EQUIPMENT; ELECTRICAL SYSTEM:SOFTWARE

## NHTSA's summary

This technical bulletin provides repair information to correct a customer concern of Head Up Display \(HUD\) Blank, Non\-Responsive to Brightness, Aim, or Page Controls, DTC U1518 Set.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2022/MC-10214208-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2022/MC-10214208-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Electrical system, Equipment and accessories, Software

## Trouble codes named

U1518

## Vehicles listed

- 2019 to 2022 CADILLAC XT4
- 2019 to 2022 CADILLAC XT5
- 2020 to 2022 CADILLAC XT6

## Other bulletins for the same vehicles and component

- [PIT5954C](/bulletins/10253085.md), 2024-04-15, Service bulletin: ELECTRICAL SYSTEM:SOFTWARE. This Preliminary information communicates a Radio software update resolution for OnStar LED Red And Wifi Hotspot Inoperative After Remote Vehicle Start concern.
- [20\-NA\-132](/bulletins/10252774.md), 2024-04-05, Service bulletin: ELECTRICAL SYSTEM; ELECTRICAL SYSTEM:12V/24V/48V BATTERY; ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL; EQUIPMENT. This warranty administration bulletin provides policy information on the requirements for 12V battery testing and warranty replacements.
- [PIP5632G](/bulletins/10230683.md), 2023-01-30, Service bulletin: ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary Information communication provides information to the technician that General Motors Technical Assistance Center may ask for Global Diagnostic System 2 Session Log. Technician will need use Global Diagnostic System 2 to send the session logs to General Motors Technical Assistance Center for further assistance on the vehicle in question.
- [PIP4902Q](/bulletins/10230682.md), 2023-01-30, Service bulletin: ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary Information communication provides information to the technician that General Motors Technical Assistance Center may ask for Global Diagnostic System 2 Session Log. Technician will need use Global Diagnostic System 2 to send the session logs to General Motors Technical Assistance Center for further assistance on the vehicle in question.
- [PIP5814](/bulletins/10230680.md), 2023-01-30, Service bulletin: ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:OTHER:OWNERS/SERVICE/OTHER MANUAL. This Preliminary information communicates that there some service parts released to dealers missing software.
- [21NA024](/bulletins/10214205.md), 2022-06-21, Service bulletin: ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT:APPLIANCE:AIR CONDITIONER; ENGINE. This technical bulletin provides repair information to correct a customer concern of Service Engine Soon MIL Illuminated with DTC P2B87 Set.
- [21NA256](/bulletins/10207916.md), 2022-02-14, Service bulletin: ELECTRICAL SYSTEM:SOFTWARE; ENGINE AND ENGINE COOLING:ENGINE:ENGINE CONTROL MODULE \(ECU/ECM\); EXTERIOR LIGHTING. This service bulletin provides repair information for dealers/technicians to correct a customer concern of a Malfunction Indicator Lamp Illuminated with DTC P26BB Set.
- [PIP5675G](/bulletins/10206730.md), 2022-01-24, Service bulletin: ELECTRICAL SYSTEM:SOFTWARE; EQUIPMENT. This Preliminary information communicates to the dealer that a customer may comment that the MIL light is illuminated. The technician may find P1098 and/or P26BB set current or history. That this may be caused by a software anomaly, and that GM is currently looking into the issue. It provides testing and related direction based on the results.
- [21NA252](/bulletins/10205574.md), 2021-12-27, Service bulletin: EQUIPMENT; PARKING BRAKE:ELECTRICAL; ELECTRICAL SYSTEM:SOFTWARE. This technical bulletin provides repair information to correct a customer concern of Electronic Park Brake Applying Intermittently After Vehicle Shutdown without DTC?s.
- [20NA171](/bulletins/10205543.md), 2021-12-27, Service bulletin: EQUIPMENT:ELECTRICAL:RADIO/TAPE DECK/CD ETC.; ELECTRICAL SYSTEM:SOFTWARE. This service bulletin provides repair information to correct a customer concern of software issues with Radio Software Version V808.

JSON: [/v1/bulletins/10214208](/v1/bulletins/10214208)

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