Ken & Ed's Auto Service - A malfunction indicator lamp (MIL), also known as a check engine light, is a telltale to indicate malfunction of a computerized engine management system. It is
Green LED Pilot Lamp (IP55) - Lewden
16mm 12v custom car symbol waterproof ip67 indicator lamp with wire-Led Indicator
A look inside some eBay panel indicators. (with LED based rectifier!) - YouTube