How to repair the Antminer S19 hash board?

How to repair the Antminer S19 hash board?

The Antminer S19 was first released by Bitmain in May 2020, and has since released other sub-models of the S19 series. Compared with the extremely high failure rate and unrepairability of the S17 series miners, the S19 series miners have higher stability and hash rate. Although released more than 2 years ago, it is still the market's most popular model of Bitcoin miner. According to market research, the failure rate of the S19 series is less than 2%. Still, the maintenance difficulty is also more complicated than the previous models, and the cost of repairing an S19 hash board is also more expensive.
To repair the hash board, you usually need to understand its circuit design. Friends new to the S19 hash board can check the Antminer S19 hash board maintenance guide that Zeus Mining shares. This guide can help you quickly understand the design of the S19 hash board and gives some maintenance ideas. According to the guide, the S19 uses an APW12 power supply. Therefore, preparing the APW12 1215 power supply and power adapter cable for the power supply before maintenance is recommended.
When we get the faulty S19 hash board, we need to check its appearance first. Clean the surface first; if the PCB is deformed or burned, it must be treated first. Then, remove the burnt or offset parts, clean the PCB, and reinstall with good parts. When installing, you need to pay attention to the model, and the performance must be the same as the original parts. It is usually necessary to use test fixtures for auxiliary inspection for hash boards with no abnormal appearance.
When using the S19 series tester for the first time, it is necessary to update the tester, flash the master program, and then load the test file. According to the guidelines, the S19 series test fixtures contain 2 test files, PT1 and PT2. Among them, PT1 is only used to find the number of chips and does not include chip responses. The PT2 test file is used to test the response rate of the chip.
When the hash board is not running, we usually choose the PT1 test file to check. The test results will usually reveal the cause of the failure. Usually, the following situations:

1. Display "EEPROM NG"

EEPROM is an essential component of the hash board, which stores the hash rate program of the hash board. Once the program of the component is wrong or the chip is not detected, it will cause the entire hash board to fail to continue testing. Usually, in this case, you first need to use a programmer to rewrite the correct running program file. If the error is still reported after rewriting the program, you must check whether the chip has solder joints. Remove the chip, remove the old solder and impurities, and add the new paste to re-tin the chip pins. And after re-soldering, use a multimeter to check whether the ground value of each pin of the chip is correct. If the solder is complete and the ground value is within the normal range, but the hash board still displays the error, then there is a problem with the chip; replace it.

2. Display "PIC sensor NG"

The result indicates that the reading temperature of the hash board is abnormal, and the temperature sensor needs to be checked. For example, on the S19 hash board, there are 4 temperature sensor chips in total. But we usually need to check whether the resistors located at R24 to R27 are abnormal and then check whether the soldering of pin 2 and pin 3 of the PIC chip is normal. Finally, check whether the 4 temperature-sensing chips on the back of the hash board and the resistance on the front are normal. It is enough to add welding or replace the chip with abnormality.

3. The number of displayed ASICs is 0 or less than 76

When the hash board has passed the EEPROM, PIC, and temperature detection, it will start to find the number of chips. If the detection result is a certain number, the communication connection of the signal is disconnected. The maintenance method is to find the chip at the reporting position. You can use the CO signal interception method to check, re-solder, or replace the chip at this position and the next chip. If it changes from a certain number to 0 after maintenance, the signal transmission connection is normal, and it is necessary to check the short circuit chip.
If ASIC is displayed as 0, you first need to check whether the voltage of each voltage domain on the hash board is normal. If the domain voltage is abnormal, you need to check the power supply; if the domain voltage is normal, you need to check the RI signal. First, determine the voltage domain where the RI is abnormal, check out the chip with a short circuit, and perform secondary tinning or replacement of the faulty chip.

4. Display "Pattern OK."

This result appears when using the PT1 test file, which means that the running circuit of the hash board has been successfully repaired. Next, you need to use the PT2 test file to check whether the chip response rate of the hash board is normal. If the test result of PT2 shows Pattern NG, the response nonce data is incomplete. According to the test results, replace the chip with an abnormal response rate in the voltage domain.
After the repair, the hash board must be tested 2 to 3 times with a test fixture. If the test passes 2 times, the hash board is normal. After completing the hash board repair, it is necessary to clean the residual thermal grease on the surface of the chip and its heat sink and then apply new thermal grease. After the radiator is installed, it is necessary to install the hash board back into the machine for the whole machine test.
The above is the maintenance guide extracted from the S19 hash board maintenance manual provided by ZEUS MINING. For more detailed guides on course maintenance, please check out the ZMRC Maintenance Training Academy launched by ZEUS MINING, which includes detailed maintenance course videos and professional technical guidance, providing a strong guarantee for your mining maintenance road.