GM Service Manual Online
For 1990-2009 cars only

Lights-On Warning

When the headlamp switch is in the PARK or HEAD position, a ground signal is applied to the lights-on warning buzzer of the headlamp switch. When the LH front side door is opened, a ground signal is applied to the lights-on warning buzzer of the headlamp switch. If the headlamp switch is in the PARK or HEAD position and the LH front side door is opened, the lights-on warning will activate to remind the driver that the headlamp switch is in the PARK or HEAD position.

Key-In Warning

When the ignition key is placed into the ignition switch, voltage is applied to the key-in warning buzzer of the gauge cluster. When the LH front side door is opened, a ground signal is applied to the key-in warning buzzer of the gauge cluster. If the ignition key is in the ignition switch and the LH front side door is opened, the key-in warning will activate to remind the driver that the ignition key is in the ignition switch.

Fasten Seat Belt Warning

When the driver's seat belt buckle is unlatched, the seat belt switch is open. With the ignition switch turned to the ON position, the fasten seat belt warning will activate after four seconds. The warning will sound for approximately eight seconds or until the driver's seat belt buckle is latched. The warning can be activated only once during an ignition cycle.

Low Engine Oil Pressure Warning

When the engine is running and oil pressure is normal, the engine oil pressure indicator switch is open. If the oil pressure drops below normal and the engine RPM is greater than 1000 RPMs, the switch closes. The low engine oil pressure warning will activate for eight seconds.