Lighting accent, LED spotlights with lighting pipes, includes lit door sill plates

Years 2008–09, 2014, 2016, 2025–26 Models 4 Factory citations 10

Query this via API →

Also described as Lighting, interiorLamp package, interior, deluxeLighting, interior ambient accent

Also documented for Buick Chevrolet GMC

Documented applications

CT4 — Alpha 2 (2020–2026)

2025–2026 Factory-verified

Premium Luxury, Sport, V-Series, V-Series Blackwing: S

GM factory document — 2025 cadillac ct4 fleet order guide, p.2.
GM factory document — 2025 cadillac ct4 v ct4 v blackwing fleet order guide, p.3.
GM factory document — 2026 cadillac ct4 fleet order guide, p.3.
GM factory document — 2026 cadillac ct4 v ct4 v blackwing fleet order guide, p.3.

CTS — Sigma II (2008–2015)

2008–2009, 2014 Factory-verified

The 2014 guides call it LED accent lighting with lighting pipes; Performance: O (in Y40); Premium: included; CTS-V Coupe, CTS-V Sedan: S

GM factory document — 2008 cadillac cts rpo code list, p.1.
GM factory document — 2009 cadillac cts rpo code list, p.1.
GM factory document — 2014 cadillac cts coupe and cts v coupe fleet order guide wayback, p.1.
GM factory document — 2014 cadillac cts v sedan fleet order guide wayback, p.2.

SRX — Theta Premium / GMT166 (2010–2016)

2016 Confirmed

not offered on Standard; GM's 2016 SRX order guide (GM Authority's copy, published September 18, 2015)

XT4 — E2 (2019–2025)

2025 Factory-verified

Premium Luxury, Sport: S

GM factory document — 2025 cadillac xt4 fleet order guide, p.2.
GM factory document — 2025 cadillac xt4 fleet order guide rpo codes, p.1.

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