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I have an Admiral ADG7005AWW dryer. The timer dial has stopped advancing, so the dryer just stays on indefinitely. I'm trying to determine the problem.

This troubleshooting guide says it could either be the timer motor or the cycling thermostat. I've tested both of them according to the instructions given on that page, and both passed the test. I took it farther and tested the cycling thermostat to make sure it is closed at room temperature and open at hot temperature using a hair dryer, as described in this video. It worked as expected. I even check the third terminal (orange wire in the wiring diagram) to make sure that it toggles opposite that of the purple wire. Again, works perfectly.

I tested the timer motor resistance, and it is 2.4kOhm, which is right where it is expected to be. I can manually turn the timer, so I don't believe it is mechanically blocked. I also rotate the timer through its full rotation and confirmed that the internal switches are connecting the YL-GY connection properly and the GY-OR connection according to the "cycle schedule" that is at the top of my wiring diagram.

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What's left? Why else would the timer not advance? The dryer works otherwise.

2 Answers 2

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The gearing of the timer allows you to turn the knob without turning the motor. The motor is probably a small conventional synchronous motor. You can easily remove the motor with 2 screws, then test to see if it turns freely. There are internal gears so you can't turn the motor with your fingers. The motors are listed by output rpm, for example 30 rpm. If the motor turns under power, then try to stop the output gear with your fingers. It should keep turning. If the motor is good, then there is a problem in the switch gears.

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  • ok, so bottom line is that I need a new timer switch? If there's no other component in the dryer for me to test, then I guess I just need to replace the timer switch. I'm not too concerned about what, specifically, failed inside the switch - I just want to know what component to replace.
    – rothloup
    Apr 12, 2022 at 12:23
  • I would make sure the switch has power coming into it, and you can see/hear the motor gear turning when the knob is moved from the OFF position.
    – John Canon
    Apr 12, 2022 at 13:33
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So in my case, the answer was to take the motor off of the motor-timer switch assembly and put it back on.

I took it off in order to inspect the assembly and see if maybe something was just stuck. I found no issue, and I put it back on.

Then I tested the motor directly by re-wiring the terminals to bypass the switches and put line voltage directly onto the motor terminals (BE CAREFUL if you try this! you are dealing with line voltages which can kill you! Unplug the dryer before you even remove the access panel). This put the motor into an "always on" condition, so I could hear and see the timer advance while the motor was applied.

I then re-wired it back the way it's supposed to be and now it works fine.

I could find nothing else wrong with the dryer, as stated in my original question.

I suspect the motor was just stuck (dryer is quite old) and maybe just needed to be re-seated. If this happens again, I'll grease the gears.

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    Nice job. It's easy if you are careful. Good warnings for everyone. It doesn't take much to jam the gears ... the motor has some torque but is easily stopped. Did you check the motor gear for wear grooves? Growing up, I would take everything apart, even a wind-up alarm clock at age four. I got in trouble because I couldn't put it back together. Now I am an Electronics Technician and a Licensed Mechanic. Still having fun.
    – John Canon
    Apr 12, 2022 at 23:04
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    LOL thanks John! I took apart VCRs. Sometimes I got them back together before my parents got home and they had no idea. Other times...not so lucky.
    – rothloup
    Apr 13, 2022 at 3:16

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