The Jeep Liberty fog light utilizes a 9145 bulb size for the specific lighting component located on the front of the vehicle. Data for the bulb size covers the range from 2008 to 2012.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Jeep Liberty uses the 9145 bulb for the front fog light position across the 2002-2012 model years.
The 9145 is a single-filament halogen bulb operating at 12V and 42W, fitted with a PY20d base, which is a bayonet-style base with a lateral pin offset designed to prevent incorrect installation.
The PY20d base on the 9145 is keyed, meaning it accepts only one rotational orientation during installation.
The 3157 bulb serves the rear fog light position on the Jeep Liberty for the 2003-2007 model years.
The 3157 is a dual-filament wedge bulb of the T25 form factor, rated at 12V with a high filament draw of 27W and a low filament draw of 7W, allowing it to serve two distinct lighting functions within a single housing.
Both the 9145 and 3157 conform to ANSI standards applicable in the United States and Canada, indicating standardized electrical and photometric performance requirements.
The 9145 and 3157 are electrically and physically incompatible with each other due to differing base types, filament counts, and wattage ratings, making cross-position substitution not possible.
The rear fog light fitment on the Jeep Liberty covers a shorter model year span than the front fog light position, with the 3157 specification present only through 2007.