Chevrolet Astro Parking Brake Indicator Bulb Size

The Chevrolet Astro parking brake indicator utilizes bulb sizes 194, PC74, and PC194 according to the provided technical specifications for the lighting components. Available data covers the time range from 1985 through 2001 for the specified vehicle and lighting application.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1995-2001	PC74
1993-1994	PC194 (With Digital Inst. Cluster)
1993-1994	PC74 (Without Digital Inst. Cluster)
1985-1992	194

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T5) with printed circuit board twist-lock socket, for instrument clusters. 12V, 1.4W.	PC74
ANSI standard (US & Canada). Miniature wedge bulb (T10) with printed circuit board twist-lock socket, for instrument clusters. 12V, 3.78W.	PC194
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W.	194

Other Locations

Additional Notes

The PC74 bulb is the most widely specified type across this application, covering the Chevrolet Astro from 1995-2001 without exception, and also applying to 1993-1994 models without a digital instrument cluster.
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, and it conforms to ANSI standards for the US and Canadian markets.
The PC194 is a T10 miniature wedge bulb rated at 12V and 3.78W, also using a printed circuit board twist-lock socket. It draws significantly more wattage than the PC74, making the two types electrically and physically non-interchangeable despite both being designed for instrument cluster applications.
For the 1993-1994 Chevrolet Astro, the correct bulb type depends on instrument cluster configuration. Vehicles equipped with a digital instrument cluster require the PC194, while those without require the PC74.
The standard 194 bulb, specified for 1985-1992 models, shares the T10 form factor and the 12V, 3.78W electrical rating with the PC194, but it lacks the printed circuit board twist-lock socket. This socket difference means the 194 and PC194 are not interchangeable even though their electrical characteristics are identical.
The transition from the standard 194 bulb to the PC-prefixed variants reflects a shift in socket interface between the 1992 and 1993 model years, where printed circuit board mounting became the applicable fitment for this indicator position.