# Over\-the\-air update 661.21

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: Over\-the\-air update
- NHTSA id: 11031827
- Published by NHTSA: 2026\-05\-01
- Manufacturer's number: 661.21
- Manufacturer's date: 2026\-04\-28
- Campaign id or software version: 661.21
- NHTSA component: UNKNOWN OR OTHER
- Manufacturer's system: TCP: TCP \(Telematics Communication Platform\)

## NHTSA's summary

• Improvements to the performance of vehicle software updates. • Fixes to help prevent loss of functionality for connectivity features, including maps and Wi\-Fi. • Fixes to help prevent erroneous emergency calls from vehicle. • Fixes for deleting digital keys. • Fixes to help ensure proper functionality for mobile app features. • Improvements to the performance of Super Cruise.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031827-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031827-9999.pdf)

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

## Vehicles listed

- 2025 CADILLAC ESCALADE
- 2025 CADILLAC ESCALADE ESV
- 2025 CHEVROLET SUBURBAN 1500
- 2025 CHEVROLET TAHOE
- 2025 GMC YUKON
- 2025 GMC YUKON XL

JSON: [/v1/bulletins/11031827](/v1/bulletins/11031827)

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