Tech Sheet Do not discard AI Electrical Shock Hazard Disconnect power before servicing. eplace all parts and panels before operating. Failure to do so can result in death or electrical shock. PECAUTIOS TO BE OBSEVED BEFOE AD DUI SEVICI TO AVOID POSSIBE EXPOSUE TO EXCESSIVE MICOAVE EEY a. Do not operate or allow the oven to be operated with the door open. b. Make the following safety checks on all ovens to be serviced before activating the magnetron or other microwave source, and make repairs as necessary:. Operation 2. Proper Door Closing 3. Seal and Sealing Surfaces (Arcing, ear and Other Damage) 4. Damage to or oosening of Hinges and atches 5. Evidence of Dropping or Abuse c. Before turning on microwave power for any service test or inspection within the microwave generating compartments, check the magnetron, waveguide or transmission line, and cavity for proper alignment, integrity and connections. d. Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation and transmission systems shall be repaired, replaced, or adjusted by procedures described in service manual before the oven is released to the owner. e. A microwave leakage check to verify compliance with the Federal Performance Standard should be performed on each oven prior to release to the owner. f. Do not attempt to operate the oven if the door glass is broken. 8205288 / 469-65-9886 FO SEVICE TECHICIA S USE OY
T 52 2P8 32 Y P8 P63 75Y/5C 70 Y/3C elay Board CD UIB P58 Touch Panel Board P3 P2 7 //0 C 74 /2C 73 /2C Hood ight P73 67 P74 38 8P8 II DIAAMS Schematic Diagram 2P84 T H H 3 Y 5 P84 M elay 4903 2 7 C702 2 C703 E70 45 Y/ 47 46 Magnetron D O. MU-056 ire Color - Brown ire o. - 72 / 3C ibbon Cable / 3 Core Primary 23 O 20V/25V, 60Hz 4 2 22 Y 5 CF AC ine P32 Cy P33 D Coil Cx Cx VD 55 5P8 28 Monitor 2P83 TT P83 Base 50 6P8 4P8 3P8 Cy 37 49 39 36 35 6 P 2 P 7P8 62 P34 P3 42 Y 33 63 Y 60 59 O 9P8 64 Door FS P62 VD VD C P35 P53 P54 76 Color/5C 3600 CF FCFA TT P57 P67 P64 P56 P66 CF elay 490 TT elay 4906 M elay feedback 56 53 3 34 65 66 500mA 470 P6 500mA elay Control Board 77 /8C P86 P6 54 UIB Thermistor P2 P85 FCFA elay 4907 elay 4930 elay 493 elay 4932 27 42 P55 Magnetron Thermistor P5 P65 72 /3C P68 37 58 C70 Secondary 24 Motor Capacitor 0uF 3P82 2P82 P82 Humidity Sensor 22 Y 8 26 aveguide 29 Hood Exhaust Fan Motor P2/P3/P32/P33/P34/P35/P5//P53/P54/P55/P56/P57 /P58/P6/P62/P63/P64/P65/P66/P67/P68/P7/P72/P73/ P74/C70/C702/C703: ire to PCB Connectors P8/P82/P83/P84/P85/P86: ire to ire Connectors Condition: Door Open. Symbol otes C amp CF Cooling Fan Motor P /2 Power esistor : Brown O: Orange : hite : reen Y: Yellow : Black : Blue : ed Hood Exhaust Fan Motor Hood amp (Cooktop amp) H Y: ray Turntable Motor TT T: Transparent 2
Parts ayout (not to scale) AA A B C D E F H X BB CC A. Humidity sensor B. thermostat opens at 329ºF (65ºC), closes at -22ºF (-30ºC) C. aveguide thermostat opens at 257ºF (25ºC), closes at -95ºF (-35ºC) D. AC line filter E. elay board F. Magnetron thermistor. Magnetron H. Secondary interlock switch I. Ferrite ring Z Y S X V U J. K. Cooling fan motor. Motor capacitor M. Monitor interlock switch. Primary interlock switch O. elay control board P. ine fuse (20 amp) Q. holder. Hood exhaust fan motor S. Hood (cooktop) lamps T. Power resistor- (20 ohm/25 ) T S Q P O M U. Power resistor-2 (4 ohm/50 ) V. Base thermostat closes at 40ºF (60ºC), opens at 04ºF (40ºC). Turntable motor X. Touch panel (back and front views) Y. lamp Z. Hood/light switch AA. Door control assembly (back view) (includes touch panel only) BB. UIB (user interface board) CC. CD module K I J Primary, Secondary, and Monitor Checkout Procedure Check By Door Open Door Closed Primary Secondary Monitor. Unplug microwave oven or disconnect power. 2. Disconnect the wires at the Primary. 3. Check from the common terminal (brown wires) to the normally open terminal (brown/white wires).. Unplug microwave oven or disconnect power. 2. Disconnect the wires at the Primary. 3. Check from the common terminal (brown wires) to the normally closed terminal (orange wire).. Unplug microwave oven or disconnect power. 2. Disconnect the wires at the Secondary. 3. Check from the common terminal (green/blue wires) to the normally open terminal (gray/blue wires).. Unplug microwave oven or disconnect power. 2. Disconnect the wires at the Monitor. 3. Check from the common terminal (blue wire) to the normally closed terminal (white wire). - + + - - + + - (+) Continuity (-) o Continuity 3
OTE: These diagrams are not intended to show a complete circuit; they represent the position of switches during DOO OPE or DOO COSED (continuity checks only). Door Closed (C) Primary (O) (O) (C) (O) Monitor Do not continue with the diagnostics of appliance if the household fuse is blown, a circuit breaker is tripped or if there is less than 20-volt power supply at the wall outlet. Complete the following steps before checking microwave oven circuitry:. Unplug microwave oven or disconnect power. 2. Check for loose wiring or incorrect wiring within microwave oven. and Magnetron Circuit Secondary Door Open (C) Primary TOUBESHOOTI (O) (O) (C) (O) Monitor Secondary 3. Disconnect white wire from power transformer and discharge high-voltage capacitor. 4. All testing must be done with an ohmmeter having a sensitivity of 20,000 ohms per volt DC or greater, and powered by at least a 9-volt battery. 5. All operational checks using microwave energy must be done with the microwave oven loaded with a minimum of 8 oz (250 m) of water in a microwave-safe container. Primary elay Board 500mA 470 2 M elay 4903 ibbon P56 0 Cable P66 ibbon elay Control Board Cable 3 2 P65 C70 2 3 aveguide Secondary 2 C702 Magnetron C703 Hood Exhaust Fan on ow Speed elay Board 500mA P5 470 4P54 2P82 5P8 Motor Capacitor Y 4P53 3P82 8P8 elay 4930 P2 P P54 P82 Power Power 3P8 esistor-2 esistor- aveguide 4
Hood Exhaust Fan on High Speed elay Board 500mA P5 470 4P54 2P82 5P8 Motor Capacitor Y 4P53 3P82 8P8 elay 4930 P2 P P54 P82 Power Power 3P8 esistor-2 esistor- Y elay 4932 2P54 Y 7P8 3P54 9P8 O aveguide Hood Exhaust Fan on Medium Speed elay Board 500mA P5 470 4P54 2P82 5P8 Motor Capacitor Y 4P53 3P82 8P8 elay 4930 P2 P P54 P82 Power Power esistor-2 esistor- 3P8 Y 2P54 Y 7P8 elay 493 aveguide Hood Exhaust Fan on MAX Speed Manually elay Board 500mA P5 470 4P54 2P82 5P8 Motor Capacitor Y 4P53 elay 4930 3P82 8P8 O 3P54 P82 9P8 elay elay 4932 493 aveguide Hood Exhaust Fan on MAX Speed Automatically elay Board 500mA P5 2P82 5P8 470 4P54 Motor Capacitor Y 4P53 3P82 8P8 aveguide P82 Base 4P8 5
Cooling Fan Motor Circuit elay Board CF P83 2P83 Y 2P53 4P53 CF elay 490 2 0 A m p 500mA P5 470 aveguide Turntable Motor Circuit TT 6P8 P53 elay Board TT elay 4906 5P8 4P54 500mA P5 470 aveguide Door Open Oven ight is On elay Board Primary P5 470500mA 42 500mA aveguide O P62 P55 2P55 3P55 2 3 P6 elay Control Board 2 P63 amp Cooktop ight on Variable ight elay Board 470 P5 P5 2 500mA 2 P58 2P8 aveguide 2P84 T T Y H H P8 Y P84 6
Touch Panel and elay Control Board Tests Touch Panel To access the test mode:. Unplug microwave oven or disconnect power. 2. Open the microwave oven door. 3. Press and hold OFF/CACE. 5. elease OFF/CACE and close microwave oven door. OTE: If the OFF/CACE key is pressed during this diagnostic routine, you will exit the test mode. Test Mode Table Screen Display Display Explanation Screen Display Display Explanation UIB S ver Version number of UIB (user interface board) software Touch panel Touch panel error PB S Ver Flash Version number of power board (relay control board) software EEPOM Version number of PB (relay control board) EEPOM (Electrically Erasable Programmable ead-only Memory) UIB thermistor (ºC) The temperature (ºC) measured by UIB thermistor ranges about 5ºC above room temperature, if oven has not been used recently M reply error Smps FB error Hum sensor error M relay error feedback error Humidity sensor error Magnetron thermistor (ºC) HUM PM Hood Key The temperature (ºC) measured by magnetron thermistor maximum 25ºC Humidity level inside unit ranges between 8,000 and 9,500, depending on humidity level in oven cavity Hood key number thermistor error Magnetron thermistor error EEPOM error thermistor error Magnetron thermistor error EEPOM (Electrically Erasable Programmable ead-only Memory) error. Place 8 oz (250 m) of lukewarm water in the center of the microwave oven. 2. Operate on HIH power level for 2 minutes. ater should be hot. Microwave Oven Power Output Test OTE: If the water takes longer than 2 minutes to heat, this may indicate either the operating voltage is lower than 0 volts or there is a problem with the microwave oven. 7
Failure Codes Indications OTE: Many of the problems listed in the chart below may be solved by power cycling: unplug microwave oven or disconnect power. After one minute, plug in microwave oven or reconnect power. Display ikely Failure Condition ecommended epair Procedure F.E elay control board defective. Unplug microwave oven or disconnect power. 2. eplace the relay control board. 3. eplace all parts and panels before operating. F2.H Hood keys stuck. Unplug microwave oven or disconnect power. 2. eplace hood/light switch. 3. eplace all parts and panels before operating. F2.H2 F2.Q Hood/light switch defective ot reading keypad inputs. Unplug microwave oven or disconnect power. 2. eplace hood/light switch. 3. eplace all parts and panels before operating.. Unplug microwave oven or disconnect power. 2. eplace the user interface board (UIB). 3. eplace the door control assembly. 4. eplace all parts and panels before operating. 5. Plug in microwave oven or reconnect power. F3.H Humidity sensor. Unplug microwave oven or disconnect power. 2. Check connection to relay control board. 3. eplace humidity sensor. 4. eplace all parts and panels before operating. 5. Plug in microwave oven or reconnect power. 6. If problem persists, unplug microwave oven or disconnect power. 7. eplace relay control board. 8. eplace all parts and panels before operating. 9. Plug in microwave oven or reconnect power. F3.T UIB (user interface board) thermistor. Unplug microwave oven or disconnect power. 2. Check the connections from the UIB to the relay control board. 3. eplace all parts and panels before operating. 5. If problem persists, unplug microwave oven or disconnect power. 6. eplace relay control board. 7. eplace all parts and panels before operating. 8. Plug in microwave oven or reconnect power. 9. If problem persists, unplug microwave oven or disconnect power. 0. eplace the UIB.. eplace all parts and panels before operating. 2. Plug in microwave oven or reconnect power. F3.T3 Hood thermistor. Unplug microwave oven or disconnect power. 2. Check hood thermistor connection. 3. eplace the hood thermistor. 4. eplace all parts and panels before operating. 5. Plug in microwave oven or reconnect power. 6. If problem persists, unplug microwave oven or disconnect power. 7. eplace the relay control board. 8. eplace all parts and panels before operating. 9. Plug in microwave oven or reconnect power. 8
Display ikely Failure Condition ecommended epair Procedure F3.T4 Magnetron thermistor. Unplug microwave oven or disconnect power. 2. Check magnetron thermistor connection. 3. eplace the magnetron thermistor. 4. eplace all parts and panels before operating. 5. Plug in microwave oven or reconnect power. 6. If problem persists, unplug microwave oven or disconnect power. 7. eplace the relay control board. 8. eplace all parts and panels before operating. 9. Plug in microwave oven or reconnect power. F6 M relay. Unplug microwave oven or disconnect power. 2. Check the cable from elay 4903 to inverter. 3. Check to see if the relay (4903 on relay control board) contact has welded closed. 4. eplace all parts and panels before operating. 5. Plug in microwave oven or reconnect power. 6. If problem persists, unplug microwave oven or disconnect power. 7. eplace relay board. 8. eplace all parts and panels before operating. 9. Plug in microwave oven or reconnect power. 0. If problem persists, unplug microwave oven or disconnect power.. eplace relay control board. 2. eplace all parts and panels before operating. 3. Plug in microwave oven or reconnect power. F7 F9 Power to magnetron interrupted elay control board communications error. Unplug microwave oven or disconnect power. 2. After 40 seconds, check to see whether this solves the problem. 3. Unplug microwave oven or disconnect power. 4. Check cooling fan operation 5. Check the magnetron. 6. Check P65 connection on the relay control board. 7. Check the P56/P66 connection between relay board and relay control board. 8. Check wiring to the 200 inverter and control system. See Checking s. 9. Check operation of all interlock switches. 0. eplace all parts and panels before operating.. Plug in microwave oven or reconnect power. 2. Check voltage at 4903- on relay board. If it is 20, unplug microwave oven or disconnect power. 3. eplace inverter. 4. eplace all parts and panels before operating. 5. Plug in microwave oven or reconnect power. 6. If problem persists, unplug microwave oven or disconnect power. 7. eplace relay control board. 8. eplace all parts and panels before operating. 9. Plug in microwave oven or reconnect power. 20. If problem persists, unplug microwave oven or disconnect power. 2. Check for reversed plug connection on controls or loose wiring. 22. eplace all parts and panels before operating. 23. Plug in microwave oven or reconnect power.. Unplug microwave oven or disconnect power. 2. Check the communications cable from P66 to P56 between relay control board and relay board. 3. eplace all parts and panels before operating. 5. If problem persists, unplug microwave oven or disconnect power. 6. eplace the relay board and relay control board. 7. eplace all parts and panels before operating. 8. Plug in microwave oven or reconnect power. 9
Display ikely Failure Condition ecommended epair Procedure F9.Q Touch communication. Unplug microwave oven or disconnect power. 2. Check the communications cable from UIB to the touch panel board. 3. eplace all parts and panels before operating. 5. If problem persists, unplug microwave oven or disconnect power. 6. eplace the door control assembly. 7. eplace all parts and panels before operating. 8. Plug in microwave oven or reconnect power. Component Tests Unplug microwave oven or disconnect power. emove the lead wires from the related component before conducting any of the following tests. Discharge the high-voltage capacitor and remove the lead wires from the primary winding of the high-voltage transformer before conducting any of the following tests. All operational checks using microwave energy must be done with the microwave oven loaded with a minimum of 8 oz (250 m) of water in a microwave safe container. IMPOTAT: Conduct a microwave energy test after performing any tests or repairs to the microwave oven. Check that all wire leads are in the correct position before operating the microwave oven. rasp wire connectors when removing the wire leads from microwave oven parts. All testing must be done with an ohmmeter having a sensitivity of 20,000 ohms per volt DC or greater, and powered by at least a 9-volt battery. Components Tests/esults Magnetron. Unplug microwave oven or disconnect power. 2. emove wire leads. Check that the seal is in good condition. Filament terminals: ormal: ess than ohm Filament to chassis: ormal: Infinite Cooling Fan Motor. Unplug microwave oven or disconnect power. 2. emove wire leads. ormal: 4 +/- 5 ohms Turntable Motor. Unplug microwave oven or disconnect power. 2. emove wire leads. ormal: 2.2k +/- 0.5k ohms (approximate) Hood Exhaust Fan Motor. Unplug microwave oven or disconnect power. 2. emove wire leads. Pins and 2: ormal: 7 +/- 5 ohms; Abnormal: Infinite Pins and 3: ormal: 2 +/- 5 ohms; Abnormal: Infinite 23 AC ine. Unplug microwave oven or disconnect power. 2. emove wire leads. P34 P33 P3 and P32, P33 and P34: ormal: reater than or equal to 300k ohms; Abnormal: ess than or equal to 00k ohms P3 P3 and P34, P32 and P33: ormal: 0 ohms; Abnormal: reater than or equal to P32 00k ohms 0
Components Tests/esults 2 3 Humidity Sensor. Unplug microwave oven or disconnect power. Y/ 2. emove the 3-pin connector from elay Control Board. 3. Measure resistance across pins and 3, and across pins 2 and 3: ormal: 2.8k ohms (approximate) at 77º +/- 0ºF (25º +/- 0ºC) s / aveguide Base OTE: efer to Parts ayout for opening and closing temperatures.. Unplug microwave oven or disconnect power. 2. emove wire leads. 3. Measure continuity: and aveguide s: ormal: Continuity; Abnormal: Infinite Base : ormal: Infinite; Abnormal: Continuity Magnetron Thermistor. Unplug microwave oven or disconnect power. 2. emove wire leads. ormal: 0k +/- 5% ohms at 77ºF (25ºC) Motor Capacitor. Unplug microwave oven or disconnect power. 2. emove wire leads. ormal: Momentarily 0 ohms, then goes to infinite / Hood amp. Unplug microwave oven or disconnect power. 2. emove wire leads. ormal:.5 +/- 0.5 ohms elay Control Board 32 P62 P6 652 P63 P74 P73 P7 P66 700 P65 P67 P64 4625 P68 OTE: Do not try to repair or make adjustments to the relay control board.. Unplug microwave oven or disconnect power. 2. Check wiring to relay control board. 3. Visually inspect P6, P62, P63, P64, P65, P66, P67, P68, P7, P73 and P74 to see whether there are signs of overheating or any signs of failure due to loose wires, bad crimping, etc. Hood / ight P2 P22 450 4502 4503 OTE: Do not try to repair or make adjustments to the hood/light switch.. Unplug microwave oven or disconnect power. 2. Check wiring to hood/light switch. 3. Visually inspect P2 to see whether there are signs of overheating or any signs of failure due to loose wires, bad crimping, etc. Power esistor- (20 ohm/ 25 ). Unplug microwave oven or disconnect power. 2. emove wire leads. ormal: 20 +/- 2 ohm at 77ºF (25ºC) Power esistor-2 ( 4 ohm/50 ). Unplug microwave oven or disconnect power. 2. emove wire leads. ormal: 4 +/- 2 ohm at 77ºF (25ºC) elay Board 574 P57 P58 P56 4903 4932493 570 P54 470 42 39 P54 4905 4924 4904 494 P53 P5 4907 490 4906 30 OTE: Do not try to repair or make adjustments to the relay board.. Unplug microwave oven or disconnect power. 2. Check wiring to relay board. 3. Visually inspect P5,, P53, P54, P55, P56 and P57 to see whether there are signs of overheating or any signs of failure due to loose wires, bad crimping, etc.
Checking s Measure Oven Input Current 5A Amps Connect an ammeter (Valhalla Scientific 20 or equivalent recommended) to measure the input current of microwave oven when the power level is set to evel 0 at the touch panel. If more than 0.5A: The 200 inverter is probably OK. Check the magnetron. See Magnetron test in Component Tests. If less than 0.5A: There is no input to the 200 inverter. Check the following:. Unplug microwave oven or disconnect power. 2. o AC voltage supply. Check relay control board and wiring. 3. o control signal. Check relay control board and wiring. Check the 200 H A B C OTE: Do not try to repair the inverter board, nor try to make any adjustments to the board. Check wiring to 200 inverter:. Unplug microwave oven or disconnect power. 2. Visually inspect 4 connectors on the 200 inverter board, C70, C702, C703, E70, to see whether there are signs of overheating or any signs of failure due to loose wires, bad crimping, etc. D F A. C702 B. Heat sink C. E70 D. High-voltage output to magnetron E E. C703 F. Control signal in/out. C70 H. 20V AC 8205288 / 469-65-9886 3/06 FO SEVICE TECHICIA S USE OY