Even a small component can cause unpredictable and unpredictable failures.

A few days ago, I took over a vehicle with a scrambled digital display. Normally, when the vehicle is in gear 2, it should display the number 2. However, when the vehicle is in gear 2, it shows not a 2, but some incomplete strokes. When you put it on the other gears, the digital display is incomplete and not in the same position.

This car has just been repaired in another repair shop. The master diagnosed that the shift display light was broken. Because there was no accessories in that shop, the car owner came to my shop to ask for replacement.

After picking up the car, I checked the vehicle first and communicated with the owner while checking. I understood the previous maintenance situation. I also thought that the display part was damaged, so I took out the new accessories to install according to the owner's requirements.

After the installation is complete, open the key to test drive. The neutral display is normal, the number 0 is very complete, in turn, put into other gears, check the display situation, put the file immediately blinked, 1 to 5 or confused code can not see clearly, can not see what is displayed.

The owner thinks I used fake products, accessories are not good, it is fake. In order to prove that I never use fake accessories, I took down the newly changed gear display light and experimented directly on the battery. At this time, it showed that everything was normal, so the owner had nothing to say.

However, at this time also confused me, in the car why the display is not normal?

The maintenance of this car seems to have been misled by the customer. It is obvious that the display light is not damaged, but caused by the wiring.

The picture

During maintenance, I once accidentally touched the electric start switch. The key of the car was not off, and the car suddenly jumped out of control. This is an abnormal condition. The driver must have short-circuited the electric start protection switch on the clutch.

First check this and then, after inspection, it is confirmed that this fault exists, and it is solved smoothly.

Although this with fault has been solved, but think carefully, this fault does not affect the gear display light ah, what is the cause of abnormal display? There seems to be a fault, and one that we haven't encountered before during maintenance.

So seriously disassemble the relevant circuit, fortunately I also have a certain circuit knowledge, otherwise it is really blind, after careful inspection, found that is the neutral display line of the diode burned, before also did not pay attention to this small component, did not think of its damage can lead to gear display disorderly code.

It wasn't readily available either, so I found a rechargeable diode on the AX100 to replace it, reset the gear display, and troubleshoot the problem.