Chevrolet Astro Check Engine Bulb Size

The Chevrolet Astro check engine light requires PC74 and PC194 bulb sizes for the instrument cluster components. Data for the specified lighting components covers the range from 1993 to 2001.

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
1996-2001	PC74
1995	PC194
1993-1994	PC194 (With Digital Inst. Cluster)
1993-1994	PC74 (Without Digital Inst. Cluster)

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

Other Locations

Additional Notes

The check engine light on the Chevrolet Astro uses one of two bulb types across its model years: the PC74 or the PC194, both of which are ANSI-standardized miniature wedge bulbs fitted with printed circuit board twist-lock sockets designed for instrument cluster applications.
The PC74 is a T5 form factor bulb rated at 12V and 1.4W, while the PC194 is a T10 form factor bulb rated at 12V and 3.78W. The PC194 operates at nearly 2.7 times the wattage of the PC74, and the two are not interchangeable due to their differing physical sizes and power draws.
The Chevrolet Astro used the PC74 bulb as the check engine light fitment from 1996-2001, representing a consistent specification across that six-year span.
The 1995 Astro used the PC194 exclusively for the check engine light, without any cluster-type variation noted for that year.
For the 1993-1994 Astro, the correct bulb type depends on the instrument cluster configuration. Vehicles equipped with a Digital Instrument Cluster require the PC194, while those without it require the PC74.
The instrument cluster type in the 1993-1994 Astro is therefore a critical factor in fitment. Installing a PC74 in place of a PC194, or vice versa, would result in an incorrect fit due to the size difference between the T5 and T10 wedge bases.