Mack DMM Courtesy Bulb Size
The Mack DMM courtesy light uses 912 and 1003 bulb sizes depending on the specific production period for the heavy truck. Available information covers the time span from 1981 through 1997.
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 |
|---|---|
| 1996-1997 | 1003 |
| 1995 | 912 |
| 1993-1994 | 1003 |
| 1991-1992 | 912 |
| 1990 | 1003 |
| 1989 | 912 |
| 1987-1988 | 1003 |
| 1986 | 912 |
| 1985 | 1003 |
| 1984 | 912 |
| 1983 | 1003 |
| 1981-1982 | 912 |
Bulb Specifications
| Description | Bulb Size |
|---|---|
| ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W. | 1003 |
| ANSI standard (US & Canada). Wedge bulb (T15). Variant of 921. 12V, 12W. | 912 |