DTC B1905/74: Short in Front Pretensioner Squib LH Circuit; DTC B1906/74: Open in Front Pretensioner Squib LH Circuit; DTC B1907/74: Short to GND in Front Pretensioner Squib LH Circuit; DTC B1908/74: Short to B+ in Front Pretensioner Squib LH Circuit [08/2013 - ]: Wiring Diagram
WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.