Microtech
© 1998-2002 J. Carlton Gallawa
All Rights Reserved Worldwide
Last updated 1/2002
Finally, the all-in-one microwave resource!

This page includes case histories of the brands:

Sunbeam to Whirlpool

Page 3

 

Instructions On How To Use These Repair Histories For Troubleshooting And Repairing Microwave Ovens

  1. After reading the safety precautions, find the brand and model number, or the number closest to the model you are repairing (you may want to use your browser's find feature).
  2. Find the symptom(s) that most closely match the symptom(s) being displayed by the oven you are repairing.
  3. Follow the specific troubleshooting and/or repair instructions to complete the repair. Click on highlighted text for a detailed explanation of that procedure.
  4. Since this database is constantly being updated and appended, if you don't find what your looking for, try again at a later time.
  5. Click here    if you would like to be notified by e-mail when this page is updated.
We hope that you find the information here helpful...

Please Note:

We hope that you find the information here helpful.. .

  Important Safety Information

Important safety information about microwave ovensRepairing a microwave oven is a dangerous task. For your personal safety, please do not proceed unless you fully understand and are prepared to follow carefully these appropriate safety precautions ..

Disclaimer: The author assumes no liability for any incidental, consequential or other liability from the use of this information. All risks and damages, incidental or otherwise, arising from the use or misuse of the information contained herein are entirely the responsibility of the user.  Although careful precaution has been taken in the preparation of this material, we assume no responsibility for omissions or errors.

© 1996-2002 J. Carlton Gallawa
All Rights Reserved Worldwide
© Copyright Information
   


 

MICROWAVE OVEN REPAIR CASE HISTORY DATABASE (CONT'D)

SUNBEAM
Model: 24011
Symptom: Microwave mode does not work-perhaps accompanied by an electrical burning odor.
Problem: Weakened fuse clips on fuse receptacle causing fuse to melt due to resistive heat. Usually indicated by a bead of solder leaching out from either endcap and/or evidence of overheating (burned spot) at the terminal connection. Also several other connections have burned loose, as indicated by discolored, melted connectors and insulators. In addition, the high-voltage transformer is shorted.
Test: High-Voltage Transformer Test
Solution: Replace fuse ($1.00) and fuse receptacle ($3.00). Also, inspect wiring for burned connections. Repair or replace as necessary. Replace high voltage transformer-price:about $50.00
TAPPAN
Model: 56-2146/02, 56-2533, 56-3354/04, 56-4274, 56-9439
Symptom: Dead. May have gone dead either immediately after starting cook, or sometime during cook.
Problem: Weakened fuse clips on fuse receptacle causing fuse to melt due to resistive heat. Usually indicated by a bead of solder leaching out from either endcap and/or evidence of overheating (burned spot) at the terminal connection
Solution: This model is designed with the fuse holder as part of the power cord. Thus, the entire assembly must be replaced. Otherwise, clean and tighten the fuse clips. Then, solder the new 20 amp fuse into the receptacle to insure a durable connection.
TAPPAN
Model: 56-3664-10/02116
Symptom: Seems to operate, but it does not heat.
Problem: Defective interlock switch
Test: Interlock Switch Test
Solution: Replace defective interlock switch. Generic switches are available at appliance parts suppliers. Contact current rating must meet or exceed that of the original, and terminal configuration must be appropriate.
TAPPAN
Model: 56-4799/03
Symptom: Plugged into wrong voltage. Now dead.
Problem: Varistor on low voltage transformer shorted out and blew the fuse.
Solution: . Replace varistor. Install new 20 amp fuse.
TAPPAN
Model: 56-4901-10
Symptom: Weak heat
Problem: The magnetron filament connectors have loosened and, due to resistive heat, the terminal connections have deteriorated and burned off of the terminals
Solution: Repair defective terminals as follows:Either (1) Cut away burned wire, clean the magnetron terminals, and replace the slip-on connectors, or (2) Cut away burned wire and connector(s). Clean terminals to prepare for soldering. Solder filament leads directly to magnetron terminals. Be careful not to apply soldering heat any longer than necessary. Note:If the magnetron terminals are burned too severely, the magnetron may need to be replaced.
TAPPAN
Model: 56-9532/02
Symptom: Dead
Problem: Broken connection at pin #3 on main harness connector.
Solution: Repair cracked solder connection on printed circuit board.
TAPPAN
Model: 56-4878-10/01
Symptom: Control panel dead.
Problem: Low voltage transformer on control board has open primary winding.
Solution A: Tappan (Frigidaire) would have you purchase the entire control panel assembly (Touch Panel Complete), the cost of which is beyond what's reasonable or practical.
Solution B: Seek out a cooperative local repair shop who may have a supply of used circuit boards. If a similar low-voltage transformer can be located, replace the defective one. If a used board cannot be located, send us E-Mail
THERMADOR
Model: MC17
Symptom: No heat.
Problem: Shorted magnetron tube.
Test: Magnetron Test
Solution: Replace magnetron. Thermador part # 14-29-102
THERMADOR
Model: MC17, MC19
Symptom: Fan making noise.
Problem: Fan mounting dampers deteriorated, allowing fan assembly to drop down so that fan blade scrapes and binds.
Solution: Replace dampers, part # 19-09-747. Reinstall blower assembly.
TOSHIBA
Model: ER-855BT-4
Symptom: Weak heat-won't pop popcorn
Problem: Weak magnetron tube
Test: Power Output Test
Test: Magnetron Test
Solution: Replace magnetron. Most appliance parts suppliers handle a line of reliable replacement magnetrons priced at about $45.00 - $60.00
TOSHIBA
Model: ERS-6631B
Symptom: Hear a clicking sound when pads are pressed, but it but won't start
Problem: Defective membrane touch panel
Solution: Replace touch panel
WESTINGHOUSE
Model: KM485LXM1KLJ2660
Symptom: Gradually decreasing output power
Problem: The magnetron filament connectors have loosened and, due to resistive heat, the terminal connections have deteriorated and burned off of the terminals
Solution: Repair defective terminals as follows:Either (1) Cut away burned wire, clean the magnetron terminals, and replace the slip-on connectors, or (2) Cut away burned wire and connector(s). Clean terminals to prepare for soldering. Solder filament leads directly to magnetron terminals. Be careful not to apply soldering heat any longer than necessary. Note:If the magnetron terminals are burned too severely, the magnetron may need to be replaced.
WHIRLPOOL
Model: MH6700XV-1
Symptom: Shortly after starting to cook, the oven tripped the circuit breaker. Now it is dead.
Problem: Shorted high voltage transformer
Test: High-Voltage Transformer Test
Solution: Replace high voltage transformer, part # 815129, price $104.00. Also replace line fuse.
WHIRLPOOL
Model: MW1500XS-0
Symptom: Some number on the touch panel will not respond.
Problem: Faulty touch panel
Solution: Replace touch panel (key unit). Part # ????. Price ????
WHIRLPOOL
Model: MW3500XS-0
Symptom: Control panel just beeps at random.
Problem: Defective key pad (touch panel)
Solution: Replace key pad. Part # 4158199. Price:about $50.00
WHIRLPOOL
Model: MW8500XR, MW8520XP, MW8550XL, MW8650XR, MW8650XS, MW8750XP
Symptom: Weak or uneven heat
Problem: Broken stirrer belt
Solution: Replace stirrer belt. Part # 311958 Price:$5.00
WHIRLPOOL
Model: MW8520XP
Symptom: Clock counts down but nothing else works
Problem: Deteriorated and cracked solder connections on printed circuit board.
Solution: Inspect circuit board, and repair deficient solder joints as necessary.
WHIRLPOOL
Model: MW8600XR
Symptom: (1) Oven starts and counts down, but does nothing else. (2) Also, the front panel frame is falling off
Problem: (1) Cracked and burned solder joints at main harness plug on the printed circuit board. (2)The front panel is mounted by means of screws that thread into plastic standoffs, which are mounted on the control panel frame. In time, these standoffs deteriorate and break off, allowing the panel frame to come loose.
Solution: Clean, reinforce and re-solder the pins where the main wiring harness plug connects into the circuit board. Also, because the cost of a new front panel frame is inexplicably exorbitant, the frame can be secured using a good quality two-sided tape
WHIRLPOOL
Model: MW3500XM
Symptom: Some pads will not respond to programming.
Problem: Defective mylar touch panel.
Solution: Replace touch panel, part # 788039
End section R to Z

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Parts Suppliers and Manufacturer Contacts

You can contact these parts suppliers and microwave oven equipment manufacturers directly for replacement parts, product literature, dealer locations, technical assistance, etc. Please e-mail additions or corrections to: j.gallawa@cox.net
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