# Over\-the\-air update 653.20

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: 11027912
- Published by NHTSA: 2026\-02\-01
- Manufacturer's number: 653.20
- Manufacturer's date: 2026\-01\-07
- Campaign id or software version: 653.20
- NHTSA component: UNKNOWN OR OTHER
- Manufacturer's system: VICM: VICM \(Vehicle Integration Control Module\)

## NHTSA's summary

• Improvements to battery health diagnostics. • Fixes for efficiency when using fast charging stations. • Improvements to reliability for climate control and charging. • Improvements to the accuracy of efficiency values. • Improvements to shifting. • Fixes to protect battery health and adjust charge limits.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11027912-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11027912-9999.pdf)

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

## Vehicles listed

- 2024 to 2026 CHEVROLET BLAZER EV

JSON: [/v1/bulletins/11027912](/v1/bulletins/11027912)

[Report an error on this page](https://github.com/wenmar-pro/wenmar-open/issues/new?template=data_correction.yml&title=Data%20correction%3A%20Over-the-air%20update%20653.20&page=https%3A%2F%2Fopen.wenmarpro.com%2Fbulletins%2F11027912&vehicle=Over-the-air%20update%20653.20)