Chevrolet Astro High Beam Indicator Bulb Size

Additional Notes

• The PC74 is a T5 miniature wedge bulb rated at 12V and 1.4W, fitted with a printed circuit board twist-lock socket designed for instrument cluster use. It is the high beam indicator bulb for the Chevrolet Astro across the 1995-2001 model years, as well as for 1994 models without a digital instrument cluster.
• The PC161 and PC195 are both T10 miniature wedge bulbs with printed circuit board twist-lock sockets, also rated at 12V and intended for instrument clusters. Despite sharing the same T10 envelope and socket type, they carry distinct ANSI part numbers and are not listed as interchangeable with each other.
• For the 1994 Chevrolet Astro, the correct high beam indicator bulb depends on instrument cluster type. Vehicles with a digital instrument cluster require the PC161, while those without require the PC74. These two bulbs differ in both physical size and socket design, making substitution between them incorrect.
• The 1993 Astro presents a similar cluster-dependent split, with the PC195 specified for the digital instrument cluster variant and the PC74 for the non-digital variant. The PC195 is a T10 bulb, whereas the PC74 is a T5, so the two are physically incompatible.
• The 1992 Astro uses the 194 bulb, a standard T10 miniature wedge type rated at 12V and 3.78W. This is a higher wattage than the 161 bulb used in surrounding years, and the 194 lacks the printed circuit board twist-lock socket found on the PC-series bulbs.
• The 161 bulb, a T10 miniature wedge type rated at 12V and 1W, is specified for the Astro across the 1985-1991 model years. At 1W, it draws less power than the 194 used in 1992, and it does not use a printed circuit board socket.
• The PC-series bulbs (PC74, PC161, PC195) are distinguished from the standard 161 and 194 types by their printed circuit board twist-lock sockets. This socket design is specific to instrument cluster assemblies that use a PCB interface rather than a conventional bulb socket, and the two socket types are not interchangeable.
• All bulb types listed across the full 1985-2001 model range conform to ANSI standards applicable in both the United States and Canada, and all operate on a 12V electrical system.