Precision Timing with the CMS MTD Endcap Timing Layer for HL-LHC

The CMS MIP Timing Detector (MTD) is designed to provide precise timing information targeting a system-level resolution of $\sim$ 40 ps per layer for charged particles. The MTD provides near-hermetic coverage up to a pseudo-rapidity of $\mid \eta \mid =$ 3 and will comprise a barrel and two endcap detectors. The Endcap Timing Layer (ETL) covers the high-radiation region 1.6 $< \mid \eta \mid <$ 3.0 and will be instrumented with silicon-based Low-Gain Avalanche Diodes (LGADs). We will provide an overview of the ETL design and present recent results from the R\&D and test beam studies of the LGAD and the readout ASIC performance.