If you have a problem with the card reader, a hardware expert is here to help

There should be a problem with the adapter of the memory card, or a problem with the card reader.

1。Try inserting a normal SD card into the card reader to see if it can read normally, if it reads normally then it is a problem with the adapter, if it is still not normal then it is a problem with the card reader.

2。Try to plug the mini SD into the adapter and connect it to another normal card reader, if it can read normally, then it is a card reader problem, if it cannot read normally, then it is an adapter problem.

If the adapter is damaged, then it is good to replace the adapter, otherwise you will have to change the card reader.

Since MP4 works, it should be that your card reader slot is in bad contact or broken. The card reader should not be able to read the card. My phone is Soai's, and the memory card I use is a memory stick.

I've had a similar problem with you. I directly spent 15 yuan to buy a multi-functional card reader, and the problem was solved directly.

If the card reader is broken, it's good to pull it if you change it, it's cheap, it may be a problem with contact, is there something dirty in the card slot, or the diode inside is faulty, or the chip is burned, there are too many pins, etc.

I've had a similar issue before, also a Nokia phone, probably a card reader compatibility issue.

I've had this problem before, I have a card problem, I suggest you try it with a different card reader.

It's that the card reader and the card are not in good contact.

It must be a problem with the card reader!

Reasons why the card reader can't read the memory card and how to fix it.

1. Insert the card reader into another computer, if it can be read, there is a problem with the memory card.

2. If the contact between the card reader and the memory card is poor, you can use an eraser to wipe the metal part of the memory card and try again.

3. Change the card reader plug in, if it is read out, it may be a problem with the card reader, and you need to change the card reader.

4. If it is a problem with the computer, you need to install the driver, click Start - Control Panel - Add New Hardware - Find, and then find if there is an external device, if there is any, you can open and click on the hardware, uninstall the driver, and then insert the card reader and reinstall the driver.

5. Restore the computer, start-run, enter sfc scannow enter, and then insert the system disk to repair.

"The card reader cannot read the data, first check the card reader from the device manager to see if there is a yellow symbol, if so, reinstall the driver to see if the card reader can work normally.

Secondly, from the hardware point of view, if the card reader card slot pin is bent, it can be manually straightened and used, if the card reader chip is broken, it cannot be repaired, and you can only buy a new one. "

Check to see if the contacts inside are not in good contact, and wipe the contacts clean with a rubber wipe.

Summary. Find the cause of the abnormal card reader1Confirm whether the card reader is normal 1、Replace the abnormal card reader with the normal card reader for testing; 2. Take the card reader to the controller for close testing. 2. Check the installation environment of the card reader1, and confirm whether the card reader is installed back to back (the spacing must be greater than 30mm); 2. Confirm whether it is installed on the metal surface; 3. Confirm whether there is strong electromagnetic equipment interference (the card reader needs to be wired separately).

3. Power supply test of the card reader: 1. Confirm whether the card reader is truly grounded; 2. Power supply stability of the card reader; 3. Power supply stability (if UPS power supply is used, the test will be removed).

If the card reader is abnormal, check whether the card reader configuration and card reading program are normal.

Find the cause of the card reader's speed and coarseness 1 to confirm whether the card reader is normal 1. Swap the abnormal card reader with the normal card reader for testing; 2. Take the card reader to the side of the controller and test it away from the town in the acre. 2. Check the installation environment of the card reader1, and confirm whether the card reader is installed back to back (the spacing must be greater than 30mm); 2. Confirm whether it is installed on the metal surface; 3. Confirm whether there is strong electromagnetic equipment interference (the card reader needs to be wired separately). 3. Power supply test of the card reader: 1. Confirm whether the card reader is truly grounded; 2. Power supply stability of the card reader; 3. Power supply stability (if UPS power supply is used, the test will be removed).

Can you elaborate on that a little bit more?

Precautions 1: To connect the card reader separately for testing, you need to check whether the card reader is normal; 2. The card reader needs to be co-located with the controller when the power supply test is separated; 3. If the normal card reader is connected to the 485 communication board, it will chirp, then the calibration time is sufficient; 4. Quietly let the same card flash two card numbers on the card reader, then the card is a composite card or the card reader is damaged.