Chart B1, Ignition Enable Circuit
WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 1990 Pontiac Bonneville, 1990 Oldsmobile Ninety-Eight, 1990 Oldsmobile Eighty-Eight, 1990 Cadillac Fleetwood, and 1990 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
Ignition enable circuit energizes EBCM to perform self-diagnosis and initialize system. Battery voltage is supplied through ignition switch to 5-amp fuse No. 8, from the fuse to EBCM pin No. 2. Ground circuit is through pin No. 1 on circuit 450 to left front fender.