Notes On Intermittents
WARNING: This page is about a different car, the 1988 Cadillac Seville and 1988 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
Check for NSBU switch and transmission indicator out of adjustment. Check for open or short to ground in circuit No. 434 between ECM and switch. Check for open to ground on switch pin "B".
Review snapshot data parameters stored with this code to verify failure condition. If failure condition is verified, check and repair intermittent wiring connections or sensor.