how to hook up a tachometer

• 2022-06-11

To hook up the automobile tachometer , first, it is difficult to remove the guard plate by yourself. Second, the line should come from the gate post, which is ugly. Third, the red cable is connected to the fuse box, and the tachometer power cannot be disconnected even if the key is removed.

After the wire is threaded in, open the engine compartment, open the rubber seat at the position shown in the figure, insert a screwdriver, insert a thin iron wire under the instrument panel in the cockpit, and pull out the  wire under the instrument panel. In this way, the  wire will smoothly reach the engine compartment.

Black cable: the black line is from the negative pole to the negative pole of the battery. The blue line is used to control the brightness of the tachometer. When driving at night, the LCD brightness of the tachometer will become weak after turning on the lights, so as not to be dazzling. Find the plug of the small night light on the left front headlamp assembly of the car (it will come down together), peel off the blue wire, insert the copper wire into the positive pole of the socket, measure the positive and negative poles with a multimeter, and then insert it into the original position. As shown in the figure, although the yellow line is connected to the lamp holder, it is actually a blue line. The original blue line of the tachometer is not long enough, so a section of yellow line is connected.

Yellow cable: the yellow line is the speed signal line, which is inserted into the left high-voltage socket near the front of the car. This is the same as the previous post, but the wiring should be kept away from the engine housing as far as possible. High temperature will accelerate the aging of the line. The redundant yellow line can be fixed to the hard rod on the right side of the engine, beautiful!

Red cable: the red line is the power line of the tachometer. In the previous post, the red line was connected to the fuse box. After my test, any contact in the fuse box will not be powered off after turning off the ignition key, so the battery power will be consumed all the time. The following is my method. The red line is still under the instrument panel. Open the fuse box under the instrument panel, pull out the ignition key, and then use the red line contacts to test the contacts in the fuse box one by one. If you find any one that won't make the tachometer light, congratulations. You found it. Because the space under the instrument panel is very small and the light is not good, I can't tell which one to connect to, and I can't take photos. You can try. Each fuse seat is 12V, which won't damage the electrical appliance, don 't worry.

Frequency point, my new Alto needs to adjust. Insert the key in the direction of the tachometer, and the speed will be displayed immediately. It's super cool, ha ha.