# Service bulletin PIC6638

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: 11027946
- Published by NHTSA: 2026\-02\-01
- Manufacturer's number: PIC6638
- Manufacturer's date: 2026\-01\-28
- NHTSA component: UNKNOWN OR OTHER

## NHTSA's summary

This Preliminary information communicates to the technician the repair direction needed to address an inaccurate speed limit sign displayed on instrument cluster.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2026/MC-11027946-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2026/MC-11027946-9999.pdf)

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

## Vehicles listed

- 2026 CADILLAC CELESTIQ
- 2026 CADILLAC ESCALADE
- 2026 CADILLAC ESCALADE ESV
- 2026 CADILLAC ESCALADE IQ
- 2026 CADILLAC LYRIQ
- 2026 CADILLAC OPTIQ
- 2026 CADILLAC VISTIQ
- 2026 CHEVROLET EQUINOX EV
- 2026 CHEVROLET SILVERADO EV
- 2026 CHEVROLET TRAVERSE
- 2026 GMC ACADIA
- 2026 GMC HUMMER EV PICKUP
- 2026 GMC HUMMER EV SUV
- 2026 GMC SIERRA EV
- 2026 GMC YUKON

JSON: [/v1/bulletins/11027946](/v1/bulletins/11027946)

[Report an error on this page](https://github.com/wenmar-pro/wenmar-open/issues/new?template=data_correction.yml&title=Data%20correction%3A%20Service%20bulletin%20PIC6638&page=https%3A%2F%2Fopen.wenmarpro.com%2Fbulletins%2F11027946&vehicle=Service%20bulletin%20PIC6638)