Chevrolet Brookwood Parking Brake Indicator Bulb Size

Additional Notes

• The Chevrolet Brookwood parking brake indicator uses two distinct bulb types across its model years: the 194 and the 257, both conforming to ANSI standards recognized in the United States and Canada.
• The 194 is a miniature wedge bulb in the T10 form factor, rated at 12 volts and 3.78 watts. The wedge base design means the bulb is held in place by tension from the socket rather than by a bayonet or screw fitting.
• The 257 is rated at 12 volts and 2 watts, and it is available in either a festoon or BA9s base configuration. A festoon bulb is cylindrical and contacts at each end, while a BA9s is a small single-contact bayonet base, making these two base types physically incompatible with each other despite sharing the same ANSI designation.
• The 1969-1972 Brookwood models use the 194 bulb for the parking brake indicator.
• The 1958-1961 Brookwood models use the 257 bulb for the parking brake indicator.
• The 194 and 257 bulbs are not interchangeable. Their base types, wattage ratings, and physical forms are all different, and substituting one for the other would result in an improper fit or incorrect electrical load on the circuit.
• The wattage difference between the two bulbs is notable: the 194 draws 3.78 watts while the 257 draws 2 watts. Installing a higher-wattage bulb in a socket rated for a lower-wattage type can place excess heat stress on the socket and surrounding components.