DTC B1900/73 Short in Front Driver Side Pretensioner Squib Circuit; DTC B1901/73 Open in Front Driver Side Pretensioner Squib Circuit; DTC B1902/73 Short to GND in Front Driver Side Pretensioner Squib Circuit; DTC B1903/73 Short to B+ in Front Driver Side Pretensioner Squib Circuit: Wiring Diagram
WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.