Gauge Indication Systems: Tachometer
WARNING: This page is about a different car, the 2002 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.
The tachometer is a 6,000 RPM tachometer. It has four terminals labeled "B" (12 to 14.5V), "S" (EDIS tach signal in), and two "G" (cylinder selection grounds). The top ground (G) terminal is open on a 4-cylinder engine vehicle, and is grounded on a 6-cylinder engine vehicle.