Door Will Not Open

Peter Kloeber  sounds like your MW has an issue with the interlock switch. Since you did not tell us teh model here is some genreal information for GE MW to check.

DOOR SENSING AND PRIMARY INTERLOCK SWITCHES

The primary interlock switch is mounted to the plastic switch bracket on the bottom, the monitor is in the middle and the door sensing switch is mounted to the upper portion of the plastic switch bracket. The power relay is mounted on the smart board. They are activated by the latch heads on the door. When the door is opened, the switches interrupt the circuit to all components, except the oven lamp. A cook cycle cannot take place until the door is firmly closed thereby activating both interlock switches. The primary interlock system consists of the door sensing switch, primary interlock switch and power relay.

MONITOR SWITCH

The monitor switch is operated (the contacts opened)indirectly by the bottom latch pawl. The pawl operates a cam switch, which in turn, actuates the monitor switch. The switch is intended to render the oven inoperative by means of blowing the monitor fuse when the contacts of the primary interlock switch and power relay fail to open when the door is opened.

Functions:

I . When the door is opened, the monitor switch contact closes (to the ON condition). At this time the primary interlock switch and power relay are in the OFF condition (contacts open).

2. As the door goes to a closed position, the monitor switch contacts are first opened and then the door sensing switch and the primary interlock switch contacts close. (On opening the door, each of these switches operate inversely.)

3. If the door is opened, and the primary interlock switch and power relay contacts fail to open, the monitor fuse blows simultaneously with closing of the monitor switch contacts.

CAUTION: Before replacing a blown monitor fuse, test the primary interlock switch, door sensing switch, monitor switch and power relay contacts for proper operation.

Primary Interlock Switch Test

Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO) terminal of the switch. The meter should indicate an open circuit with the door open and a closed circuit with the door closed. If improper operation is indicated, replace the primary interlock switch.

Please be aware that a microwave carries voltages high enough to kill you. If you have never worked on one or are unsure of working on it, contact a professional to check it for you.