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Replacement parts for Roper RES7745RQ0 29"ELECTRIC DRYER | AppliancePartsPros.comSee the attachment for the wiring diagram
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I am not sure how to test this type of switch and if this means it is shot.
You sort of lost me here.It really is not a switch but is a relay.[/COLOR]
Using the color code it looks like blue to blue should be 0 ohms when the switch is activated.
The Pink/Black connection is the relay coil. This pulls the relay contacts down and keeps them closed allowing you to release the start switch and the unit keeps running.
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Also, little black module directly next to the start switch (between the start switch and the temp knob) shows no connectivity. This part does not even show up in the dryer schematic. I assume this may be the problem.[/COLOR]
I think this is just the buzzer (Item 3 in Section 3). Continuity will depend on meter scale. Try a higher scale. In any case this should not cause your problem.
I would start by checking the power.
If the unit has an interior drum light, is it working?
If yes then you have the required 120 volts.
If no or if it does not have one then check the power.
The drum light and the motor require 120 volts (L1 to Neutral).
The heater and the timer run off of 240 volts.
So if you loose Neutral the unit will not start..
Try flipping the breaker off/on slowly a couple times. Sometimes you can loose the line without actually tripping the breaker.
Check the voltage at the plug
L1 to L2 should be 240 volts
L1 to Neutral and L2 to Neutral, both should be 120 volts.
If OK
Unplug the unit and check the wires at the terminal strip in the machine to make sure none are loose or burned out
If OK
Check the power at the terminal strip.
Do this with the heater off and on.
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Be careful as 240 volts is lethal !!![/COLOR]
If power is OK.
Unplug the unit and attach one meter lead to BK on the timer and leave it there. Set the unit to mid-cycle timed dry. Now work you way back through the motor circuit
BK to time BU should be 0 ohms.
BK to both BU on the start switch both should be 0 ohms when the start switch (relay) is activated manually.
All following tests require that the start switch be held in the start position..
BK to both sides of the thermal fuse (Item 7 in Section 1) should be 0 ohms
BK to W on the timer should be approximately 3 ohms (motor's windings)
BK to T same as above
BK to NO on the door switch same as above
BK to COM on the door switch same as above
BK to Neutral connector on the line cord same as above.
I am off to the lake for a few days so will not be available.
I hope the above will help you find the problem.