Speedometer Installation

Combination Speedometer/Tachometer

1. Connect red wire from gauge to a switched 12v source (12v switched power source means that there are 12v to the red wire when the ignition switch is on and no voltage when the ignition switch is off) Connect also to red wire on speed sender

2. Connect black wire from gauge to a good engine block ground and to black wire on speed sender.

3. Connect purple wire from gauge to the night time dimming circuit. (The purple wire must be connected to the headlight switch circuit so that there are 12v to the purple wire when the headlight switch is on and no voltage when the headlight switch is off)

4. Connect white wire from gauge to white wire from the speed sending unit

5. Connect brown wire from gauge to negative terminal on coil or to tach terminal on distributor

3 3/8” Speedometer

1. Connect red wire from gauge to a switched 12v source (12v switched power source means that there are 12v to the red wire when the ignition switch is on and no voltage when the ignition switch is off) Connect also to red wire on speed sender.

2. Connect black wire from gauge to a good engine block ground and to black wire on speed sender

3. Connect purple wire from gauge to the night time dimming circuit (The purple wire must be connected to the headlight switch circuit so that there are 12v to the purple wire when the headlight switch is on and no voltage when the headlight switch is off)

4. Connect the white wire from the gauge to the white wire from the speed sending unit

Mini-Speedometer

1. Connect red wire from gauge to a switched 12v source (12v switched power source means that there are 12v to the red wire when the ignition switch is on and no voltage when the ignition switch is off) Connect also to red wire on speed sender.

2. Connect black wire from gauge to a good engine block ground and to black wire on speed sender.

3. Connect purple wire from gauge to the nighttime dimming circuit (The purple wire must be connected to the headlight switch circuit so that there are 12v to the purple wire when the headlight switch is on and no voltage when the headlight switch is off)

4. Connect the white wire from the gauge to the white wire from the speed sending unit

NOTE: Gauge with optional memory feature will have a blue wire. Connect blue wire to blue wire from memory switch packaged with gauge. Connect black wire from memory switch to ground.