1993 Buick Riviera Owner's Manual - Page 117

Hazard Warning Flasher - Service A/C If this light stays on 60 seconds or more, your air conditioning system needs service. It comes on as a bulb cheek, whenever you turn the ignition to "Run". This light on your instrument panellets you know when you have the hazard warning flashers on. When the hazard flashers on, your turn signals will are stop not work. If you apply the brakes, the flashing will until'yourelease the brake pedal. See "Hazard Warning Flashers" in the Index for more information.