Headlamps, high intensity discharge (HID), xenon projector, flash-to-pass, automatic on and off, automatic delay, warning buzzer

Years 2012, 2015–19 Models 5 Factory citations 13

Also described as Headlamps, high intensity dischargeHeadlamps, projector beam, high intensity discharge (HID)Headlamps, HID xenon projector, flash-to-pass, automatic on and off, automatic delayHeadlamps, HID xenon projector, adaptive forward lighting, flash-to-pass, automatic on and off, automatic delay, warning buzzer

Also documented for Cadillac Chevrolet GMC

Documented applications

Cascada — Delta II (2016–2019)

2016–2019 Factory-verified

all trims: S

GM factory document — 2016 buick cascada order guide copy gm authority, p.3, p.8.
GM factory document — 2017 buick cascada order guide copy gm authority, p.3, p.13.
GM factory document — 2018 buick cascada order guide copy gm authority, p.3, p.13.
GM factory document — 2019 buick cascada order guide copy gm authority, p.3, p.13.

Envision — D2XX, imported from China (2016–2020)

2016–2019 Factory-verified

2016–2018: 1SP: S; 2019: 1SV, 1SD, 1SL: S

GM factory document — 2016 buick envision order guide copy gm authority, p.4, p.14.
GM factory document — 2017 buick envision order guide copy gm authority, p.5, p.18.
GM factory document — 2018 buick envision order guide copy gm authority, p.5, p.17.
GM factory document — 2019 buick envision order guide copy gm authority, p.5, p.20.

LaCrosse — E2XX, 3rd gen (2017–2019)

2017–2019 Factory-verified

2019: all trims: S

GM factory document — 2017 buick lacrosse fleet order guide wayback, p.3.
GM factory document — 2018 buick lacrosse order guide copy gm authority, p.4.
GM factory document — 2019 buick lacrosse order guide copy gm authority, p.6.

LaCrosse — Epsilon II, 2nd gen (2010–2016)

2012, 2015 Factory-verified

2015: 1SL, 1SP, 1SR: O; with PCI; replaced TT2 for 2012 (GM Authority 2012 RPO list)

GM factory document — 2015 buick lacrosse fleet order guide wayback, p.3.

Regal — Epsilon II, 5th gen (2011–2017)

2012, 2016 Factory-verified

replaced TT6 for 2012, with adaptive forward lighting (GM's 2012 list); 2016: 1SP, 1SX: S; bi-xenon

GM factory document — 2016 buick regal order guide copy gm authority, p.5, p.20.

This page aggregates every documented appearance of T4F in the Buick reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.