Chevrolet Blazer High Beam Indicator Bulb Size

The Chevrolet Blazer high beam indicator utilizes bulb sizes PC74, 74, 161, 194, and 168 across various production periods. Data for the specific component covers the range from 1972 through 2003.

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
1995-2003	PC74
1993-1994	74
1992	161 (With Halogen Capsule Headlamps)
1992	194 (With Sealed Beam Headlamps)
1987-1991	168
1972-1973	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 (T5). 12V, 1.4W.	74
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 1W.	161
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W.	194
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 4.9W.	168

Other Locations

Additional Notes

The PC74 bulb is the most frequently specified size across the Chevrolet Blazer high beam indicator fitments, covering model years 1995-2003. It is an ANSI-standard miniature wedge bulb in a T5 form factor, rated at 12V and 1.4W, and is distinguished from the standard 74 bulb by its printed circuit board twist-lock socket, which is designed specifically for instrument cluster applications.
The 74 bulb, specified for the 1993-1994 Blazer, shares the same T5 form factor, voltage, and wattage rating as the PC74 but lacks the printed circuit board twist-lock socket. Despite their electrical equivalence, the socket type difference means the two bulbs are not directly interchangeable in all applications.
The 1992 Blazer carries two distinct high beam indicator bulb specifications depending on headlamp configuration. Vehicles equipped with halogen capsule headlamps use the 161 bulb, a T10 wedge type rated at 12V and 1W, while those with sealed beam headlamps use the 194 bulb, also a T10 wedge type but rated at a higher 3.78W.
The 168 bulb is specified for the Chevrolet Blazer across model years 1987-1991. It is an ANSI-standard T10 miniature wedge bulb rated at 12V and 4.9W, making it the highest-wattage bulb among all the T10 types listed in these specifications.
The 194 bulb appears in two separate periods within the specifications: the 1972-1973 model years and the 1992 sealed beam headlamp variant. At 12V and 3.78W in a T10 wedge format, it draws more power than the 161 but less than the 168, placing it between those two T10-based types in terms of wattage.
Three distinct T10 wedge bulbs, the 161, 194, and 168, are each rated at 12V but differ in wattage at 1W, 3.78W, and 4.9W respectively. Although all three share the same T10 physical form factor, their differing wattage ratings reflect different electrical loads and they are not specified as interchangeable within these fitments.
The T5 and T10 designations refer to the tubular bulb body width, expressed in units of one-eighth of an inch, meaning a T5 body is five-eighths of an inch wide and a T10 body is ten-eighths of an inch wide. This physical size difference means T5 and T10 bulbs are not compatible with the same sockets.