Brother International HL-1070 Service Manual - Page 82

I-20 Horizontal lines Possible cause SR electrode SR connection failure Feed roller Step Check Result Remedy 1 Are the SR electrodes between Yes Clean both the printer body and the drum electrodes. unit dirty? 2 Are the SR electrodes between No Check the SR the printer body and the drum connection. unit connected correctly? 3 Are the feed roller shaft and the ground contact connected correctly? No Check the connection between the shaft and the ground contact. HV.GND contacts (Fig.4-5, 4-6) ➈ ➉ I-21 Light rain Note: Make the printer in the light rain test mode as follows before checking; 1. Turn on the power switch and open the top cover. 2. Hold down the panel switch until all the lamps are on, and then release the switch. Possible cause Drum unit failure SR PCB failure High-voltage power supply PCB failure Step 1 2 3 Check Is the problem solved after replacing the drum unit which contains no more starter sheet**? Is the problem solved after replacing the SR PCB? Is the problem solved after replacing the High-voltage power supply PCB? Result Remedy Yes Replace the drum unit. Yes Replace the SR PCB. Yes Replace the High-voltage power supply PCB. **Note: Make sure to use the used drum unit which has already ejected the starter sheet. It is not possible to find the drum unit failure if you use a new drum unit with the starter sheet. IV-18