1995 Pontiac Bonneville Owner's Manual - Page 308

Brake-Transaxle Shift Interlock BTSI -- Steering Column Lock While parked, and with the parlung brake set, try to turn the key to LOCK in each shift lever position. The key should turn to LOCK only when the shift lever is in PARK (P). 0 The key should come out only in LOCK. 1. Before you start, be sure you have enough room around the vehicle. It should be parked on a level surface. Parking Brake and Automatic Transaxle PARK (P) Mechanism Check 2. Firmly apply the parking brake (see "Parking Brake" in the Index if necessary). NOTE: Be ready to apply the regular brake immediately if the vehicle begins to move. 3. With the engine off, turn the key to the RUN position, but don't start the engine. Without applying the regular brake, try to move the shift lever out of PARK (P) with normal effort. If the shift lever moves out of PARK (P), your vehicle's BTSI needs service.