Standard Ignition US-139 Ignition Switch

Ignition Switch for Classic GM Applications

Standard Ignition US-139 is a column-mounted ignition switch built for older GM cars and trucks that require a direct electrical switching replacement. It uses copper alloy conductors for strong conductivity and low resistive loss, with a robust housing made from aluminum and plastic for dependable fit and function.

Compatible With 1984-1994 Pontiac Sunbird, 1984-1991 Buick Skylark, and many other Chevrolet, GMC, Oldsmobile, Cadillac, and Pontiac models listed below, this ignition switch is a practical choice for restoring key-start operation on vehicles without a tilt wheel.

Key Features

• Standard Ignition US-139 ignition switch for column mounting
• Bolt-on attachment method with one rectangular female connector
• 8 male blade terminals for vehicle-specific electrical routing
• Copper alloy conductors for stable electrical conductivity
• Black and silver finish with aluminum and plastic construction
• 100% tested for mechanical and electrical switching performance

Detailed Description

This ignition switch is engineered for service replacement on a wide range of GM platforms, including Pontiac Firebird, Chevrolet Camaro, and Buick Century applications that use a column-mounted switch. The design focuses on proper fit, consistent key-position switching, and reliable current transfer through the ignition circuit. Standard Ignition US-139 is also a useful reference when searching for an ignition switch for 1984-1989 Chevrolet Celebrity, 1984-1988 Pontiac Fiero, or 1984-1986 GMC S15 models with the listed configuration.

This part cross-references AC Delco and Dorman equivalents for the same application.

Common Problems This Part Can Help Solve

• No-crank or intermittent crank condition caused by worn switch contacts
• Accessory, ignition, or start circuit failure at the column switch
• Hard starting related to inconsistent electrical switching
• Electrical loss from degraded internal conductors or terminals
• Replacement needs after a damaged or unreliable original ignition switch

Installation Notes and Tips

Install on the steering column using the bolt-on attachment method and verify the connector style, terminal count, and mounting location before installation. This switch is not listed for vehicles equipped with a tilt wheel, and many applications also require a console-shift, no-tilt configuration. Confirm the exact year, make, model, and option package against the fitment list before ordering.

• Fits 1986-1994 Pontiac Sunbird, N/A
• Fits 1991 Buick Skylark, N/A
• Fits 1985-1986 Buick Skylark, N/A
• Fits 1990-1991 Pontiac Grand Am, N/A
• Fits 1985 Pontiac Grand Am, N/A
• Fits 1988-1990 Buick Skylark, N/A
• Fits 1984 Buick Skylark, N/A
• Fits 1984-1990 Pontiac 6000, N/A
• Fits 1986-1990 Pontiac Bonneville, N/A
• Fits 1984 Pontiac Bonneville, N/A
• Fits 1986-1990 Pontiac Firebird, N/A
• Fits 1984 Pontiac Firebird, N/A
• Fits 1984-1989 Buick Skyhawk, N/A
• Fits 1984-1989 Chevrolet Camaro, N/A
• Fits 1984-1989 Chevrolet Celebrity, N/A
• Fits 1984-1989 Oldsmobile Cutlass Ciera, N/A
• Fits 1986-1989 Pontiac Grand Am, N/A
• Fits 1988-1989 Pontiac Safari, N/A
• Fits 1984-1988 Chevrolet Monte Carlo, N/A
• Fits 1984-1988 Oldsmobile Firenza, N/A
• Fits 1988 Oldsmobile Toronado, N/A
• Fits 1984-1988 Pontiac Fiero, N/A
• Fits 1986-1987 Buick Century, N/A
• Fits 1987 Buick LeSabre, N/A
• Fits 1984-1987 Chevrolet Caprice, N/A
• Fits 1984-1987 Chevrolet Chevette, N/A
• Fits 1987 Chevrolet Corvette, N/A
• Fits 1984 Chevrolet Corvette, N/A
• Fits 1984-1987 Chevrolet El Camino, N/A
• Fits 1985-1987 Chevrolet Sprint, N/A
• Fits 1985-1987 Oldsmobile Calais, N/A
• Fits 1987 Oldsmobile Toronado, N/A
• Fits 1984-1985 Oldsmobile Toronado, N/A
• Fits 1987 Pontiac T1000, N/A
• Fits 1986 Chevrolet Astro, N/A
• Fits 1984-1986 Chevrolet C10, N/A
• Fits 1984-1986 Chevrolet C10 Suburban, N/A
• Fits 1984-1986 Chevrolet C20, N/A
• Fits 1984-1986 Chevrolet C20 Suburban, N/A
• Fits 1984-1986 Chevrolet C30, N/A
• Fits 1984-1986 Chevrolet Cavalier, N/A
• Fits 1985-1986 Chevrolet Corvette, N/A
• Fits 1984-1986 Chevrolet K10, N/A
• Fits 1984-1986 Chevrolet K10 Suburban, N/A
• Fits 1984-1986 Chevrolet K20, N/A
• Fits 1984-1986 Chevrolet K20 Suburban, N/A
• Fits 1984-1986 Chevrolet K30, N/A
• Fits 1986 Chevrolet K5 Blazer, N/A
• Fits 1984 Chevrolet K5 Blazer, N/A
• Fits 1986 Chevrolet S10 Blazer, N/A
• Fits 1984 Chevrolet S10 Blazer, N/A
• Fits 1986 GMC P2500, N/A
• Fits 1984 GMC P2500, N/A
• Fits 1986 GMC P3500, N/A
• Fits 1984 GMC P3500, N/A
• Fits 1984-1986 GMC S15, N/A
• Fits 1986 GMC S15 Jimmy, N/A
• Fits 1984 GMC S15 Jimmy, N/A
• Fits 1986 GMC Safari, N/A
• Fits 1984-1985 Buick Century, N/A
• Fits 1984-1985 Cadillac Cimarron, N/A
• Fits 1984-1985 Cadillac Commercial Chassis, N/A
• Fits 1984-1985 Cadillac DeVille, N/A
• Fits 1985 Cadillac Eldorado, N/A
• Fits 1984-1985 Cadillac Fleetwood, N/A
• Fits 1984-1985 Cadillac Seville, N/A
• Fits 1984-1985 Chevrolet Citation II, N/A
• Fits 1984-1985 Chevrolet G10, N/A
• Fits 1984-1985 Chevrolet G20, N/A
• Fits 1984-1985 Chevrolet G30, N/A
• Fits 1984-1985 Chevrolet Impala, N/A
• Fits 1984-1985 Chevrolet S10, N/A
• Fits 1984-1985 GMC C1500, N/A
• Fits 1984-1985 GMC C1500 Suburban, N/A
• Fits 1984-1985 GMC C2500, N/A
• Fits 1984-1985 GMC C2500 Suburban, N/A
• Fits 1984-1985 GMC C3500, N/A
• Fits 1984-1985 GMC G1500, N/A
• Fits 1984-1985 GMC G2500, N/A
• Fits 1984-1985 GMC G3500, N/A
• Fits 1984-1985 GMC Jimmy, N/A
• Fits 1984-1985 GMC K1500, N/A
• Fits 1984-1985 GMC K1500 Suburban, N/A
• Fits 1984-1985 GMC K2500, N/A
• Fits 1984-1985 GMC K2500 Suburban, N/A
• Fits 1984-1985 GMC K3500, N/A
• Fits 1984-1985 Oldsmobile 98, N/A
• Fits 1985 Pontiac Firebird, N/A
• Fits 1985 Pontiac J2000 Sunbird, N/A
• Fits 1984 Oldsmobile Omega, N/A
• Fits 1984 Pontiac Acadian, N/A
• Fits 1984 Pontiac Grand Prix, N/A
• Fits 1984 Pontiac Phoenix, N/A

Quality Assurance

Standard Ignition builds this switch with high-grade materials and tests each unit for both mechanical action and electrical performance before release. The copper alloy conductor design supports consistent circuit transfer in demanding service applications.