# Over\-the\-air update 661.20

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: 11031788
- Published by NHTSA: 2026\-04\-30
- Manufacturer's number: 661.20
- Manufacturer's date: 2026\-04\-14
- Campaign id or software version: 661.20
- NHTSA component: UNKNOWN OR OTHER
- Manufacturer's system: CGM, EBCM: CGM\-GTW \(Communication Gateway Module\), EBCM \(Electronic Brake Control Module\)

## NHTSA's summary

• This update contains a required software change to help improve the overall software update and diagnostics process. Be sure to install this update to be able to receive future software updates. • Improves traction and stability control when accelerating or on uneven terrain. • Improves braking and stopping performance on low\-traction surfaces. • Improves the performance of assisted braking features.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031788-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11031788-9999.pdf)

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

## Vehicles listed

- 2026 CHEVROLET EQUINOX
- 2026 GMC TERRAIN

JSON: [/v1/bulletins/11031788](/v1/bulletins/11031788)

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