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Replacement parts for AMANA LEA60AW DRYER- ELE | AppliancePartsPros.com

See the attachment for the wiring diagram

First thing to check is the power.
Try flipping the breaker off/on slowly a couple times, sometimes you can loose half the line without actually tripping the breaker.
The heating coil requires the full 240 volts.
If this does nothing, 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.
[COLOR="Red"]Be careful as 240 volts is lethal !!![/COLOR]

[COLOR="DarkRed"]What am I left with?[/COLOR]
A bad wire, timer contacts, fabric selector switch and centrifugal swich on the motor.
[COLOR="DarkRed"]
I read something about the motor containing a switch that activates heating, is this correct?[/COLOR]
Yes there is a centrifugal swich on the motor. It closes when the motor gets close to operating speed. This ensures that the heater does not come on till there is air flow.

[COLOR="DarkRed"]Is this my problem?[/COLOR]
Cannot say

If power is OK.
I would attach one meter lead to the heating element and leave it there.
Set the unit to mid-scale on a timed dry cycle and high meat.
Then work your way back to L1 component by component.
If all are OK then all that is left is the centrifugal switch.

[COLOR="DarkRed"]UNPLUGGED?[/COLOR]
Yes.
I always try to do as much testing as possible with the unit unplugged.
[COLOR="DarkRed"]
What do you think?[/COLOR]
2 to L1 are the selector switch for the main heating element.

1 and 4 change the current to the cycling thermostat's internal heater. This adds heat to the cycling thermostat making it cycle more often, resulting in lower overall heat output.
I think on high heat they both should be open.

I would check the fabric selector switch.

Next check the heating element.
Check the heating coil.
Unplug the unit and both wires to the coil.
Check it with a meter, should be around 10 to 12 ohms.
Then check from each side of the coil to the case/frame, both should be infinite ohms (open). If not the coil may have sagged or broken and is touching the case. This can cause it to run on high and the thermostats cannot regulate it.

It sounds like you are already disconnecting one side of any devise you are measuring, just to be sure that you do not read an alternate/parallel circuit path.
When checking the full heater circuit I would not do this, but would use a low meter scale. Then once you get past the heating coil you should see it's resistance.

[COLOR="DarkRed"]When you say 2 to L1, this is 2 on fabric selector and L1 on timer circuit?[/COLOR]
Yes. The wire is L1 on the fabric selector switch and H on the timer.

[COLOR="DarkRed"]1 and 4 on timer?[/COLOR]
When neither is closed the thermostat heater is off so that will be high heat.
When 1 is closed the thermostat heater is on full (120 volts across it) so that will be low heat.
When 4 is closed the thermostat heater is on but also has a 560 ohm resistor in wired series with it so that will be medium heat.

[COLOR="DarkRed"]Is there a way to tell if the motor is getting to full speed,[/COLOR]
If it is running it will be at full speed.
If it was not the unit would shut off when you released the start switch.
The second centrifugal switch removes the motor's start winding from the circuit but also gives a closed parallel path for the start switch.
[COLOR="DarkRed"]
and how often have you seen the motor/switch be the problem?[/COLOR]
That is a hard question not that common but have seen it.
The only real way to check it is with a live test.
You have to measure from L2 to the switch side of the heater. Across the switch. When the motor is off you should see 240 volts across it. When the motor is running there should be 0 volts.
I hate doing this as you are messing with 240 and are trying to hold meter leads to a shaking machine. A set of meter lead clips really is helpful here.

It can be done with the unit opened up but be careful to keep the tests short as the heating coil does not have air flow over it and will burn out if run for too long.

That is good because you now know that the centrifugal switches are OK.
So the motor which is expensive is OK.

[COLOR="DarkRed"]Can I conclude that the timer circuit is my problem?[/COLOR]
It is a definite possibility.
You could check it buy unplugging the unit and setting the timer to the different settings. M to L2 contacts should close whenever the unit should be heating.

[COLOR="DarkRed"]If it was defective, would this also cause the amount of heat to be reduced?[/COLOR]
I doubt it but it is hard to say what exactly is going on in the timer so I cannot rule it out 100%.