Testing Procedures
!WARNING
To avoid risk of electrical shock, personal injury or death; disconnect power to oven and discharge capacitor before servicing, unless testing requires power.
Illustration | Component | Testing | Results |
| Thermal cutout | Disconnect all wires from TCO. |
|
|
| Measure resistance across terminals. | Closed at 32°F (0°C) and |
|
| Cavity TCO | |
|
| Magnetron TCO | Opens at 230°F (110°C) |
|
| Closed at 140°F (60°C) and | |
|
|
| Opens at 320°F (160°C) |
| Diode | Discharge Capacitor | Infinite resistance should be |
|
|
| measured in one direction and 50KΩ |
|
| Remove diode lead from capacitor and | or more in the opposite direction. |
|
| connect ohmmeter. | NOTE: Ohmmeter must contain a |
|
| Reverse leads for second test. | |
|
| battery of 6 volts minimum. | |
| Circuit Protector | Discharge Capacitor | Infinite resistance should be |
|
|
| measured in one direction and 50KΩ |
|
| Remove diode lead from capacitor and | or more in the opposite direction. |
|
| connect ohmmeter. | NOTE: Ohmmeter must contain a |
|
| Reverse leads for second test. | |
|
| battery of 6 volts minimum. | |
| Capacitor | Discharge Capacitor |
|
|
| Remove wires from capacitor terminals | Between Terminals: Meter should |
|
| and connect ohmmeter, set on highest | momentarily deflect towards zero |
|
| resistance scale to terminals. | then return to over 5 MΩ. If no |
|
|
| deflection occurs, or if continuous |
|
|
| deflection occurs, replace capacitor. |
|
| Also check between each terminal and |
|
|
| capacitor case. | Terminal to Case: Infinite resistance |
| Magnetron | Discharge Capacitor | Between Terminals: Less than 1 Ω |
|
| Remove wires from magnetron and | Each terminal to ground measures |
|
| connect ohmmeter to terminals. Also | Infinite resistance. |
|
| check between each terminal and | Note: This test is not conclusive. If |
|
| ground. | oven does not heat and all other |
|
|
| components test good replace the |
|
|
| magnetron and retest. |
| Blower motor | Remove all wires from motor. |
|
|
| Measure resistance across coil | Approximately 31 – 35 Ω |
| Stirrer motor | Remove all wires from motor. |
|
|
| Measure resistance across terminals .... | Approximately 12 – 14 KΩ |
Secondary | Transformer | Discharge Capacitor |
|
| Remove all wires from terminals. |
| |
Filament |
| Measure resistance from: |
|
|
| Less than <1 Ω | |
Primary |
| Primary | |
| Filament | Less than <1 Ω | |
|
| ||
|
| Secondary to Ground screw on |
|
|
| transformer stack | Approximately 70 – 80 Ω |
| Lamp receptacle | Test continuity of receptacle terminals. | Indicates continuity with bulb |
|
|
| installed. |
| Wire Harness | Test continuity of wires | Indicates continuity |
20 | 16026795 | ©2006 Maytag Services |
