Fault Phenomenon: LQ-1600KIII printer is more common with parallel ports, and the proportion is large. Parallel damage can result in a lot of abnormal phenomena, such as self-test, can not connect the computer. Can you self-test? Can not be reset. There is a boot reset, can't be self-test, online. There is a control panel indicator flashing, then completely destroy. There are more other faults ... repair method 1: Check the 5V voltage on the ground with a multimeter short circuit, if the short circuit is shorted, the interface chip IC-9, 74LS06 is damaged, first pick 74LS06, then check 5V voltage Whether the situation is still short, such as a short circuit, then IC-2 has also been damaged, extracted from IC-2, E05B24YA, then test 5V voltage is not short, and replace the IC-6 and IC-2, then check the parallel socket To the interface chip to the CPU, if there is damage, it is also replaced. Start up, the printer will return to normal work. Maintenance method 2: Check the 5V voltage to the ground without a short circuit with the multimeter, then check the IC-2, E05B24YA, see any feet between the first foot of the chip and 37-54, indicating that IC-2 is damaged. In this case, IC-9 is generally damaged, and IC-2, IC-9 is required at the same time. Check the resistance around, if it is damaged, it is also replaced. Start up, the printer will return to normal work.
Problems should be paid attention to when repairing motherboards (especially LQ-1600KIII): When the chip is removed, don't pay attention to the copper platinum of the circuit board, as long as you don't remove the bad line board, if you can't repair it, others can still Help you fix the motherboard, otherwise it will cause new fault points and cause the motherboard. When loading chips, pay attention to the chip pin and pads do not be misplaced. Do not short when the soldering, the pin and the foot of the chip are short.
Fault Phenomenon: Print Disabled Steps Maintenance Method: Firstly Use the needle program to detect a few needles, after excluding the failure of the printhead and the header, then find a few needle drive tubes. Both the motherboard is marked with the number of the needle drive tube and the needle number of the needle program corresponds to the corresponding, so it is very convenient to find.
