tachometer not at zero when stopped

• 2021-12-30

Why tachometer not at zero when stopped?

The problem may be the tachometer gauge problem. The stepping motor of the instrument has a small fault. The gear inside is stuck, or the pointer and the stepping motor have a relative displacement, and the mechanical zero position is higher. That is to say, the pointer was at 0RPM after flameout, but now the stepping motor is stuck Its relative zero position is improved.

The possible problems analyzed are as follows:

1. The tachometer gauge itself is not work. It may be that the speedometer of the vehicle's instrument assembly has failed, resulting in the pointer of this meter not rotating. It may be that the wheel speed sensor of the vehicle has failed, causing the meter to stop rotating. It may be that the mileage sensor of the vehicle has failed, causing the meter to stop rotating.

2. The tachometer gauge power supply or grounding circuit is faulty.

3. The tachometer gauge data bus is faulty.

4. First check the sc13 fuse and find that it is not burnt out. Remove the tachometer gauge to measure the grounding wire. T32 / 16 pin is normal. Then measure the T32 / 32 pin at the instrument end, which shows 0V and no voltage. Then use a multimeter to measure the output pin of sc13 fuse to st31 / 32 pin of the instrument. The harness is not connected, so the fault is obvious in this place.

You need to check the details.

Solve methods of tachometer not at zero when stopped:

1. First check whether the flexible shaft is disconnected, and then check whether the mileage increases when starting. If the tachometer doesn't move. There's no need to repair it. Let's get a new one. As long as the car starts, the gears in the tachometer are rotating. They are worn out over time. The gears in the tachometer are plastic and new ones don't cost much.

2. The tachometer is generally set in the instrument panel and placed symmetrically with the speedometer. The tachometer works according to the magnetic principle. It receives the pulse signal generated when the primary current in the ignition coil is interrupted and converts this signal into a displayed speed value. The faster the engine speed, the more pulses generated by the ignition coil, and the greater the speed value displayed on the table.

If the tachometer gauge or sensor are not work , you can buy new ones to replace them. Nanjing Hemu International Trade Co.,Ltd can supply the gauges and the kit.