DTC B1925/78 Short in Rear Passenger Side Pretensioner Squib Circuit; DTC B1926/78 Open in Rear Passenger Side Pretensioner Squib Circuit; DTC B1927/78 Short to GND in Rear Passenger Side Pretensioner Squib Circuit; DTC B1928/78 Short to B+ in Rear Passenger 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.