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A while ago, I published that my flaps would deploy and would not retract. After some extensive troubleshooting, it was linked to two sealed relays. Each micro switch in the circuit was methodically checked and found OK. The relays are hard soldered to a circuit board. Mouser electronics helped cross match the relays from the currently installed part. I looked in my service manual, but could not find any information on the relays. The new relays were installed and worked flawlessly until last week. Same problem occurred! I never found a "Smoking Gun" on the first replacement, so although the problem was solved, I could not conclude how these relays got their contacts fired. We use hundreds of relays in control panels at work and I have very seldom had relay failures. So why? It turns out the Flap Target was too close the the contact wheel of the micro switches. With the aircraft on the ground, and flaps at takeoff position (and Gravity doing its thing) the separation of the target and the switch contact was enough to drop the circuit. BUT...... when the flap were generating lift, it moved the target fractions closer to the switch contact and created relay chatter. Ill admit, this was discovered by accident when a friend in the hangar happen to lift up on the flap when I was staring up at the flap motor. Sure enough, the relays started humming and the motor started pulsing. Its a wonder they lasted as long as they did!!! Just wanted to pass this along. This site should be all about passing on information to solve problems! Rick