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chevy silverado speedometer not accurate
Most of these failures are caused by the speed sensor and combination instrument. First, check whether the sensor assembly and wiring are loose, and check whether the wiring of the instrument is loose. If the wiring is OK, then it is necessary to replace the new parts and then test the vehicle for observation. First, replace a sensor and try!
Reason:
1. Fault with speed sensor and sensor drive mechanism.
2. The speedometer is faulty (speedometer).
3. The wire speed or mechanism between the sensor and the speedometer is faulty.
4. Higher grade vehicles may be related to the vehicle travel computer. According to the vehicle model, the diagnostic instrument can be used to detect, and the fault point can be easily determined.
Troubleshooting method:
There are two situations when the speedometer does not move. One is when it does not move at 0, which generally means it is broken or short-circuited; The other is to stay still at the highest point. That is what we often say when the meter runs out, it can be adjusted back. If it doesn't move at 0, and the mileage number doesn't move, it's likely that there is a problem with the speed sensor, or there is a problem with the wiring between the instrument and the sensor. Go to the factory for maintenance. It's a small problem.
Extended data:
The speedometer is at the most prominent position on the dashboard, indicating the current speed of the vehicle, in km/h, and the total mileage and short distance mileage, in km. The total mileage cannot be changed, and the single distance mileage can be reset as required. The speedometer uses a magnetoelectric ammeter as an indicator. When the vehicle is running at different speeds, the signal processing circuit converts the pulse signal input by the speed sensor into a current signal proportional to the speed, deflecting the pointer of the ammeter to indicate the corresponding speed.The odometer is a digital instrument, which engages the worm on the transmission shaft of the speedometer through the transmission gear of the counter drum to make the counter drum rotate. Its feature is that the upper drum rotates one full circle. The next drum rotates 1/10 turn. Like the speedometer, the odometer also has an electronic odometer, which obtains the mileage signal from the speed sensor. The mileage accumulated by the electronic odometer is stored in the nonvolatile memory, and the data can also be saved without electricity.
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