The 1991 Toronado and Trofeo Owner's Manual and Service Manual are in error regarding Engine Oil Life index Display and Reset Procedure. The base Toronado and Trofeo models (cars without color Driver Information Display) added Compass as a possible option and changed some of the 15-button driver information system control switch functions for 1991.
Press the "2 Options" key three times on cars equipped with both a phone and a compass, or twice on cars equipped with either a phone or a compass, or once on cars without phone or compass.
While Oil Life index is displayed, press and hold the "Reset/Enter" key at the bottom right of the 15- button switch for about five seconds.
The 1991 Service Manual, pages 0B-1 and 8C-4, should be marked with the correction. There are other corrections to pages 8C-3 and 8C-4 that will be communicated in a later bulletin.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.