Maytag MAT12PSB, MAT12PRB, MAT12PRA, MAT12PRD, MAT12PDS, MAT12PSA, MAT12PRS Electrical Troubleshooting

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Troubleshooting Procedures

!WARNING

To avoid risk of electrical shock, personal injury or death, disconnect power to unit before servicing, unless testing requires power.

ELECTRICAL TROUBLESHOOTING

The malfunction of an electrical circuit cannot easily be diagnosed unless you first understand how it functions when operating normally. The electrical schematic and wiring diagram includes a cycle sequence chart keyed to the contacts in the timer, relay and/or control switches.

!CAUTION

Resistance or continuity testing is done with the product disconnected from power. Failure to do so can result in damage to your meter.

For the most part, we will only be concerned with continuity. Is there a path or not? References are made between a “closed” (Continuity) reading and an “open (No continuity) reading. One note, when you get and “open” reading, try a higher resistance range (setting). A very high resistance appears as an “open” on the lower ranges. For best accuracy always “rezero” meter when changing ranges and/or the physical position of the meter.

Continuity testing, as related to an electrical component, is the check of a part for an “open” or closed” circuit.

Continuity test of “load” devices will show varying levels of resistance from very low for some transformer and motor windings to very high for some timer motors and components on control boards. Usually it is more important to know if there is a path for current flow through a device (continuity ) that to know the exact resistance (ohms) of the device.

Continuity tests of switches will show virtually no resistance across a closed contacts. Resistance, even low values indicate burned or dirty contacts in a switch.

When checking components or circuit paths for continuity, external wiring should be disconnected to eliminate false readings through external paths. Isolate what you want to test.

Electrical components fall into two general categories.

1.Loads - Devices that use or consume electricity. Examples would include drive motor, timer and solenoid coils.

2.Switches - Devices that control the supply of electricity to the load or loads in a circuit. Examples include lid switches, timer contacts selector switch and relay contacts.

©2003 Maytag Appliances Company

16022842 Rev. 0

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