What's the reason for the tachometer not moving?
3 Answers
The reasons for the tachometer not moving: 1. The tachometer pointer does not move due to the disconnection of the flexible shaft inside the tachometer; 2. The tachometer pointer does not move due to the pointer falling off or getting stuck; 3. There is foreign matter inside the instrument panel, preventing the pointer from rotating; 4. There is an issue with the wiring inside the tachometer, such as aging or burning out. The tachometer is an instrument used to measure the engine speed, which is essential in the mechanical industry for determining the speed, linear velocity, or frequency of a motor. The tachometer processes the received digital pulse signals, directly reads them into the CPU's counting port, calculates the speed and the corresponding position of the pointer through software, and then drives the stepper motor to rotate in positive or negative directions through the CPU's control port after amplification, indicating the corresponding speed value.
As someone who's been driving for decades, I've encountered quite a few strange dashboard incidents, like sudden tachometer failures which happen frequently. There are multiple reasons: First is the crankshaft position sensor issue, since it's responsible for measuring engine speed - sensor looseness or dirt can cause reading failures. Second is blown instrument fuses, especially in older cars where aging wiring causes overloads - just check the engine compartment fuse box to identify. Third is unstable wiring connections, like corroded or detached wire terminals where contacts disconnect due to vibration. Ignoring this poses safety risks, such as being unable to monitor abnormal overspeeding on highways which could cause accidents. I recommend first trying to clean sensor connectors with simple tools, and if that doesn't work, visit a professional repair shop for diagnosis.
When I was driving my family car, I encountered a situation where the tachometer stopped working. The car could still run, but the dashboard was acting up. Common causes include sensor failures, such as issues with the crankshaft or camshaft sensor, which affect signal transmission. Additionally, poor internal wiring connections in the dashboard can also mess up the readings, especially after driving on bumpy roads for a long time. I think the most troublesome issue is a blown fuse, which is easy to replace in the fuse box. Ignoring it can affect daily driving, as you won’t know the engine RPM, and you might feel unstable during acceleration or idling. It’s best to first check the fuses and sensor connectors yourself before heading to a repair shop.
