FIXED MED5870TW0 Dryer won't start when start button pressed

K_Richardson

Premium Member
Joined
Feb 10, 2019
Messages
5
Location
Alabama
Model
MED5870TW0
Brand
Maytag
Age
6-10 years
Dryer won't start when start button pressed. Timer ticks when control knob set, no spin, no heat.

Hello! I have a dryer problem, and I've done everything I know to do, so I'm reaching out to the wisdom of those with experience.
This is my first attempted dryer repair, and I have only casual experience in fixing appliances, so please correct me if I've done anything wrong, or if you have any suggestions to try.

It is a Maytag electric dryer, model MED5870TW0, from roughly 2008.

The current issue is this:
I was doing laundry, and I completed two loads without incident. I loaded the third load into the dryer as usual, set the control timer, and when I pushed the start button, nothing happened. I have been troubleshooting from this point.

If the dryer is plugged in and the door shut, and the control knob is turned to either "auto dry" or to "timed dry," the timer starts making a ticking sound, but nothing else occurs. If I push the start button, nothing happens. The timer continues ticking. If I turn the control knob to any of the "off" positions, the ticking stops, and the start button pops back out again.

I've been using a multimeter, and testing components according to the instructions I've found online.

I have checked the breaker box and tested the power and ground at the 220 socket, with no problems.
I have checked the 3-prong cable screwed to the block to make sure it is tight and there are no loose wires arcing.

I have checked continuity on the start switch, and it appears to be functional. When pressed, it has continuity. When the control knob is turned to "off" the button pops back out.
I have checked continuity on the exhaust thermal fuse and the thermistor, and they appear to be functional. I also bridged the thermal fuse and it still didn't start.
I have checked continuity on the thermal cutoff and inlet thermistor, and they appear within normal ranges.
The control board does not appear damaged, the resistors on it are intact, the capacitor is not leaking, and it is making good connection with the socket.

I have not tested the door switch, though I believe it is working, because the ticking in the timer stops when I open the door, and resumes when I close it, even if nothing else works.

I also attempted to "jump start" the motor by taping down the door switch, setting a drying cycle, pressing start, then manually spinning the drum to engage the motor. This did not have any effect. It does not appear to want to spin or heat, but there is resistance on the drum, so I don't think the belt is broken, and there is no sound coming from any motors, so it's either not engaging or it's broken.

I have attempted to troubleshoot the Control Timer itself, it appears something may be wrong with the timer, as I only get the expected continuity results when on the "Timed Dry" side. If I set the control dial to the "Sensor Dry" side, nothing is responding according to the testing procedure listed, though again, this may be because my schematics are not correct. The only way I know to confirm this is to blindly order a timer, but I'd like to rule out anything else before I resort to that.

I have not directly interacted with the heating element or the motor itself, because space is limited in the laundry room, but if I must access them for testing, I will do what needs to be done.

I hope this information is helpful, if any brave souls feel willing to help troubleshoot this issue. I would sure appreciate it.
If you have any suggestions or want me to re-test anything, I'll be glad to try whatever.
Thank you for reading.
 
Last edited by a moderator:

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
99,146
Location
McMullen Valley, Arizona
Hi,

Your timer sounds like the problem, but lets verify that.:)

Here's the timer for your model:
WP8566184 Timer


Do you have your wiring diagram? If not, this is the wiring diagram for your model: https://drive.google.com/file/d/1Qp9uAkThOg_mOx7RYmJaJ5GANw4LFeHW/view?usp=sharing

Look at the wiring diagram, now locate the wire on the timer that goes to M4 on the motor switch. It's the blue wire. That blue wire should be on the timer terminal marked BU.

Now the wire on M5 on the motor switch is the white wire and connects to the timer terminal marked W.

Measure the voltage between M4 and M5 on timed dry high heat WHEN you start the dryer, test between BU and W on the timer, Then report back.

Jake
 

K_Richardson

Premium Member
Joined
Feb 10, 2019
Messages
5
Location
Alabama
Thanks for the assistance, Jake.

I tested the voltage between BU and W, with the unit plugged in.
I set the heat on "high heat" and turned the dial to the middle of "Timed Dry." The timer started that ticking sound it has been doing.
I checked the voltage at that point and it was ~125vAC.
When I pressed the start button, the voltage dropped to 0 and stayed there. No other changes occurred.
 

K_Richardson

Premium Member
Joined
Feb 10, 2019
Messages
5
Location
Alabama
Also, I don't know if this is useful information or not, but just out of curiosity I was testing the other leads on the timer, according to the legend at the top of the 8566184 schematic you posted.
Am I right in assuming that at some point at least, the T-W connection should have continuity?
With the dryer unplugged, I connected the multimeter to the T and W points, and rotated the control knob a few times completely around the dial, and it never registered continuity on those 2 points.
If I pushed the start button, the multimeter would chirp to register a very brief continuity on T-W. Otherwise nothing.
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
99,146
Location
McMullen Valley, Arizona
I tested the voltage between BU and W, with the unit plugged in.
I set the heat on "high heat" and turned the dial to the middle of "Timed Dry." The timer started that ticking sound it has been doing.
I checked the voltage at that point and it was ~125vAC.
When I pressed the start button, the voltage dropped to 0 and stayed there. No other changes occurred.
Was the door closed? I forgot to tell you to make sure the door is closed first.

You did ohm test the door switch for continuity when the door switch button is pushed in?

Also Unplug the dryer, then check for continuity between BK and BU and between T and W with the timer on timed dry. If either reads open replace the timer.

Jake
 

K_Richardson

Premium Member
Joined
Feb 10, 2019
Messages
5
Location
Alabama
Yes, the door was closed at all times.
I did take the top off the dryer and test the door switch, and it is working properly.

I have unplugged the dryer, and set the dial to the middle of "Timed Dry." There is continuity between BK and BU, but there is nothing between T and W.
I have unplugged the dryer, set the dial to the middle of "Timed Dry," connected the test leads to T and W, and given the entire dial multiple full turns, and at no point does T and W ever register continuity.

In this circumstance, is it your opinion that the 8566184 timer is the defective part?
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
99,146
Location
McMullen Valley, Arizona
Yes, the timer is bad.

I posted the link to the new timer in post #2 above.

Let us know how it goes.:)

Jake
 

K_Richardson

Premium Member
Joined
Feb 10, 2019
Messages
5
Location
Alabama
As it turns out, it was in fact the timer that was causing the problem. I dropped in the replacement timer and it seems to work perfectly again.
Thank you very much for your expertise and assistance, Jake.

Out of curiosity I also removed the old timer and took it apart, and sure enough one of the leaf switches on the W-T connection inside (timer switch 4) had fused and burnt up. I hope this has had no ill effect on any other components.
Hopefully this thread is helpful to anyone else attempting to troubleshoot their malfunctioning constellation dryer.
 

Jake

Appliance Tech - Admin
Staff member
Joined
Aug 24, 2004
Messages
99,146
Location
McMullen Valley, Arizona
Excellent K_Richardson, glad to hear the new timer fixed it.:)

Thanks for the update!

sure enough one of the leaf switches on the W-T connection inside (timer switch 4) had fused and burnt up. I hope this has had no ill effect on any other components.
Yes, I've seen that before many times, the good thing is I've never seen it have ill effect on the other parts.

Jake
 
Top