194
KX-MB283BR
14.6.
MAIN BOARD SECTION
When the unit fails to boot up the system, take the troubleshooting procedures very carefully. It may have a serious problem.
The symptom: No response when the power is turned on. (No LCD display, and keys are not accepted.)
The first step is to check the power source. If there is no problem with the power supply unit, the problem may lie in the digital
unit (main board).
As there are many potential causes in this case (ASIC, DRAM, etc.), it may be difficult to specify what you should check first. If
a mistake is made in the order of checks, a normal part may be determined faulty, wasting both time and money.
Although the tendency is to regard the problem as a serious one (IC malfunction, etc.), usually most cases are caused by solder
faults (poor contact due to a tunnel in the solder, signal short circuit due to solder waste).
Note:
1. Electrical continuity may have existed at the factory check, but a faulty contact occurred as a result of vibration, etc., during
transport.
2. Solder waste remaining on the board may get caught under the IC during transport, causing a short circuit.
Before we begin mass production, several hundred trial units are produced at the plant, various tests are applied and any mal-
functions are analyzed. (In past experiences, digital IC (especially, DRAM and ROM) malfunctions are extremely rare after
installation in the product.)
This may be repaired by replacing the IC, (DRAM etc.). However, the real cause may not have been an IC malfunction but a sol-
dering fault instead.
Soldering faults difficult to detect with the naked eye are common, particularly for ASIC and RA (Resistor Array). But if you have
an oscilloscope, you can easily determine the problem site or IC malfunction by checking the main signal lines.
Even if you don’t have such a measuring instrument, by checking each main signal line and resoldering it, in many cases the
problem will be resolved.
An explanation of the main signals (for booting up the unit) is presented below.
What are the main signals for booting up the unit?
The ASIC (IC300) controls all the other digital ICs. When the power is turned on, the ASIC retrieves the operation code stored in
the ROM (IC402), then follows the instructions for controlling each IC. All ICs have some inner registers that are assigned to a
certain address.
It is the address bus by which the ASIC designates the location inside each IC. And the data bus reads or writes the data in
order to transmit the instructions from the ASIC to the ICs.
These signal lines are all controlled by voltages of 3.3V (H) or 0V (L).
Summary of Contents for KX-MB283BR
Page 9: ...9 KX MB283BR 4 2 Translation Lists 4 2 1 Error Message Display...
Page 11: ...11 KX MB283BR 6 Technical Descriptions 6 1 CONNECTION DIAGRAM...
Page 29: ...29 KX MB283BR 6 6 2 FLAT TORQUE 1 2 PHASE EXCITATION HALF STEP 1 Timing chart 2 Wave form...
Page 30: ...30 KX MB283BR 6 6 3 W 1 2 PHASE EXCITATION QUARTER STEP 1 Timing chart 2 Wave form...
Page 34: ...34 KX MB283BR 6 9 LSU Laser Scanning Unit SECTION...
Page 35: ...35 KX MB283BR...
Page 43: ...43 KX MB283BR 6 10 9 2 Drum Detection...
Page 49: ...49 KX MB283BR...
Page 54: ...54 KX MB283BR DC DC Main Board Supply...
Page 55: ...55 KX MB283BR wave form...
Page 103: ...103 KX MB283BR 11 2 7 6 LIGHT PRINT CROSS REFERENCE HIGH VOLTAGE SECTION P 128...
Page 105: ...105 KX MB283BR 11 2 8 2 THE RECORDING PAPER IS WAVED OR WRINKLED...
Page 106: ...106 KX MB283BR 11 2 8 3 SKEW...
Page 108: ...108 KX MB283BR 11 2 8 5 THE RECORDING PAPER JAM...
Page 111: ...111 KX MB283BR CROSS REFERENCE MOTOR SECTION P 120...
Page 112: ...112 KX MB283BR 11 2 9 2 SKEW ADF...
Page 114: ...114 KX MB283BR 11 2 9 6 BLACK OR WHITE VERTICAL LINE IS COPIED...
Page 115: ...115 KX MB283BR 11 2 10 AN ABNORMAL IMAGE IS COPIED CROSS REFERENCE CIS CONTROL SECTION P 124...
Page 120: ...120 KX MB283BR 11 2 14 MOTOR SECTION 11 2 14 1 ENGINE MOTOR...
Page 121: ...121 KX MB283BR 11 2 14 2 FB Flatbed MOTOR...
Page 122: ...122 KX MB283BR 11 2 14 3 ADF MOTOR...
Page 123: ...123 KX MB283BR 11 2 15 LSU SECTION CROSS REFERENCE LSU Laser Scanning Unit SECTION P 34...
Page 124: ...124 KX MB283BR 11 2 16 CIS CONTROL SECTION...
Page 125: ...125 KX MB283BR CROSS REFERENCE TEST FUNCTIONS P 73...
Page 127: ...127 KX MB283BR...
Page 128: ...128 KX MB283BR 11 2 18 HIGH VOLTAGE SECTION 1 Main...
Page 129: ...129 KX MB283BR 2 CHG GRID 3 TRA...
Page 130: ...130 KX MB283BR 3 DEV DC TRA...
Page 131: ...131 KX MB283BR 11 2 19 USB SECTION Troubleshooting 1 Confirmation of the PC settings...
Page 132: ...132 KX MB283BR 2 Confirmation of the main unit...
Page 134: ...134 KX MB283BR Waveform of normal operation...
Page 136: ...136 KX MB283BR 2 When 100Base TX enabled deviced is connected...
Page 137: ...137 KX MB283BR 3 When 10Base T enabled device is connected...
Page 140: ...140 KX MB283BR 11 2 21 MAIN BOARD SECTION 3 3V TROUBLESHOOTING GUIDE...
Page 141: ...141 KX MB283BR 1 2V TROUBLESHOOTING GUIDE...
Page 145: ...145 KX MB283BR When the document has jammed near the document exit 3 Close the ADF cover...
Page 154: ...154 KX MB283BR 12 Service Fixture Tools...
Page 156: ...156 KX MB283BR 13 1 ADF SECTION...
Page 157: ...157 KX MB283BR 13 2 REMOVE ADF SECTION 1...
Page 158: ...158 KX MB283BR 13 3 REMOVE ADF SECTION...
Page 159: ...159 KX MB283BR 13 4 REMOVE TOP COVER SECTION...
Page 160: ...160 KX MB283BR 13 5 REMOVE SCANNER GLASS SECTION...
Page 161: ...161 KX MB283BR 13 6 REMOVE OPERATION PANEL SECTION...
Page 162: ...162 KX MB283BR 13 7 LEFT SIDE SECTION 13 8 REMOVE MAIN BOARD...
Page 163: ...163 KX MB283BR 13 9 REMOVE GEAR CHASSIS SECTION...
Page 164: ...164 KX MB283BR 13 10 REMOVE PAPER FEED ROLLER 13 11 RIGHT SIDE SECTION...
Page 165: ...165 KX MB283BR 13 12 REMOVE RIGHT SIDE COVER SECTION...
Page 166: ...166 KX MB283BR 13 13 LOWER SIDE CABINET SECTION...
Page 167: ...167 KX MB283BR 13 14 REMOVE RIGHT CASSETTE GUIDE 13 15 REMOVE PICK UP BOARD...
Page 168: ...168 KX MB283BR 13 16 REMOVE HIGH VOLTAGE POWER BOARD...
Page 169: ...169 KX MB283BR 13 17 REMOVE PICK UP ROLLER UNIT...
Page 170: ...170 KX MB283BR 13 18 REMOVE LOW VOLTAGE POWER BOARD...
Page 171: ...171 KX MB283BR 13 19 REMOVE FUSER UNIT...
Page 172: ...172 KX MB283BR 13 20 Installation Position of The Lead 13 20 1 MAIN BAORD SECTION...
Page 173: ...173 KX MB283BR 13 20 2 BOTTOM PART SECTION...
Page 174: ...174 KX MB283BR 13 20 3 SIDE CABINET SECTION...
Page 175: ...175 KX MB283BR 13 20 4 HIGH VOLTAGE POWER SUPPLY BOARD SECTION...
Page 176: ...176 KX MB283BR 13 20 5 LOW VOLTAGE POWER SUPPLY BOARD SECTION...
Page 177: ...177 KX MB283BR 13 20 6 AC INLET SECTION 13 20 7 SOLENOID LEAD SECTION...
Page 190: ...190 KX MB283BR 14 4 TERMINAL GUIDE OF THE ICs TRANSISTORS AND DIODES 14 4 1 MAIN BOARD 1...
Page 191: ...191 KX MB283BR 14 4 2 MAIN BOARD 2 14 4 3 OPERATION BOARD...
Page 195: ...195 KX MB283BR 14 6 1 NG EXAMPLE...
Page 196: ...196 KX MB283BR 14 7 TEST CHART 14 7 1 ITU T No 1 TEST CHART...
Page 197: ...197 KX MB283BR 14 7 2 ITU T No 2 TEST CHART...
Page 202: ...202 KX MB283BR MEMO...
Page 211: ...211 KX MB283BR MEMO...
Page 220: ...220 KX MB283BR 17 1 2 TOP COVER SECTION...
Page 221: ...221 KX MB283BR 17 1 3 ADF SECTION...
Page 222: ...222 KX MB283BR 17 1 4 MOTOR SECTION...
Page 223: ...223 KX MB283BR 17 1 5 LOWER CABINET SECTION...
Page 224: ...224 KX MB283BR 17 1 6 UPPER CABINET SECTION...
Page 225: ...225 KX MB283BR 17 1 7 FUSER SECTION...
Page 226: ...226 KX MB283BR 17 1 8 LOWERSIDE CABINET...
Page 227: ...227 KX MB283BR 17 1 9 GEAR SECTION 1...
Page 228: ...228 KX MB283BR 17 1 10 GEAR SECTION 2...
Page 229: ...229 KX MB283BR 17 1 11 CASSETTE OUTPUT TRAY...
Page 230: ...230 KX MB283BR 17 1 12 ACTUAL SIZE OF SCREWS AND WASHERS...
Page 231: ...231 KX MB283BR 17 1 13 ACCESSORIES AND PACKING MATERIALS...
Page 240: ...240 KX MB283BR H I KXMB283BR...