Kenmore HE4 Dryer Mod# 110.95088400. With power to the unit, what voltage readings should I get at each pin for P3, P4 and P2?
I now read from .1 - .3 volts. None of my lights on the console are on when power to unit and Start is pushed. Trying to verify MCE board is good.
Thank you,
Gary
Hi Gary. I am Kelly.
Take a look at the wiring Diagram on page 63 of this 68 page .pdf file.
https://secured.whirlpool.com/Service/SrvTechAdm.nsf/2cd44500d572193285256a45004fd9d6/cdce3c10dcb5382285256aa20064beaa/$FILE/Duetdry.pdf
Check for 120V between P1 pin 5 and P1 pin 2. If you do not have that 120V then there is problem with the power coming from the door switch. I have read your posts on other sites and you were talking about why you did not have +5V on P4 pin 3. If there is not input power or the door switch has failed you will not have the +5V.
Also see page 58 of the pdf file for making sure the door switch is working properly and for performing resistance checks.
You should be able to read continuity of the door switch by reading across P1 pins 2 and 3 then opening and closing the door. If nothing happens when you open and close the door there is a problem in the door switch circuit.
To check inputs nad outputs of the board transformer check the primare winding for 120V. Usually the input power pins are pins 1 and 2 and the secondary winding either pins 3 and 4 or pins 5 and 6 depending on the tranformer that was used it can be as high as pin 8. The secondary winding pins off of the main board transformer will read either 3 V or 5 V If there is no output on the secondary winding of the transformer something is shorted in the dryer wiring harness or components causing the secondary winding to burn out. (see page 56 of the PDF figure 5-8 and the transformer I am talking about is on the left side of the board just below the circular varistor and P1.)
Sure hope this helps you resolve the issue.
Thanks for using FixYa.
Kelly
Kelly,
Sorry for the delay. Ok, here is where I'm at. I have 120V at P1 pins 5-2.
I performed the resistance tests per the manual for the door switch, checks good.
Checked continuity of switch at P1 2-3, good.
Transformer:
Looking at the board, transformer at left. Top left corner of transformer, I will call pin 1, top right pin 2, lower left pin 3 and lower right pin 6.
Pin 1 0V
Pin 2 120V
Pin 3 3.4V
Pin 4 .2V
Pin 5 .2V
Pin 6 4V
I still have no 5V at P4 pin 3, I get .1V - .3V on any of the pins for P3 or P4. The front panel is driven by this 5V, no?
I can't suspect the front controls if I can't verify power to the board from the MCE correct?
The MCE is a reman, so I have the same condition with the original and this (new) reman.
Help,
Gary
Hi Gary.
On the 6 pin 115V type input power is across terminals 1 and 4. You should see pin numbers on the circuit board. Seconday Output power is across terminals 5 and 6 (secondary winding #1) along with 7 and 8 (Secondary winding #2) BOTHmust have outputs for the main board to work. The fact that you got 3.4 V on what you labeled pin 3 is a good thing. Now it is a matter of finding out where it stops if at all. There can be either 10V or 12V off of the other winding that is used for MCB relay control power. Like I said it takes both of them having outputs for the main board to work.
Here is the kicker.... if there is a short in the dryer some where it can overload the secondary winding of the MCB and cause the dryer to burn out MCB's as fast as you install them. (Probably not what you wanted to hear)
Kelly
Kelly, I see the numbers now for the transformer, they are located on the transformer above the pins. I had to use my wives cheaters and a light to see them. Anyway, I have 14.7 V across 5-6 and 14.7 across 7-8.
I assume this means the secondaries are ok? I don't know where to go from here.
Gary
Hi Gary,
If you have the voltage of 14.7 V then the PCB transformer is ok. The voltage drops for the 3.3 V, 5.0v are done on the MCB via resistors en-route to P3 and P4. Usually the display is 3.3V and the touch pad voltage is 5.0V At this point it sounds as if there is a problem with the actual ribbons that go to the touch pad and display. Either they are not mated to the board correctly or the ribbon conductor got torn when you changed the MCB. Use the pdf file I had you download and re-check the mating of P3 and P4. The only other thing that would make any sense if that the display / touch pad is shorted. I know you said before that you had done a continuity check of the touch pad keys. I am reluctant to say change the touch pad / display at this point. I don't have an actual schematic of the MCB for this dryer.
Just a thought but this is a very long shot.... check the belt switch on the motor base. (Also in the pdf file) It is located unter the idler pully arm and is atcuated when the arm is in the down position. I.e the only way that it gets to that position is if the belt has broken. Given you had the 14.7 V off of the secondary I doubt this is the problem. I still think there is a ribbon problem with P3 and P4 to the user control panel / display.
Kelly
Gary one more thing to try is on page 50 of the pdf file it states this:
NOTE: If the “Diagnostic Test Mode” entry was
unsuccessful, perform the following actions for
specific indications.
Indication #1
Problem: None of the indicators or display
digits light.
DISPLAY FAULT/ERROR CODES
Corrective Action: Press one of the
Manual Cycles pushbuttons. If the indicators
light, change the dryer time by pressing
the More Time and Less Time pushbuttons.
If either pushbutton fails to change the
time, the pushbutton is defective, and it is
not possible to enter the diagnostic mode.
Remove the console electronics and housing
(see page 4-4). <-pdf file pg 36
That is why I said recheck the ribbons of P3 and P4.
See page 36 for releasing the ribbon clips of P3 and P4.
Access to the touchpad is gained by releasing the 6 thumb clips as seen on page 37.
Kelly
Kelly, I'm trying to verify the drum switch. I would like to restate what I know of the P3, P4, ribbon cables and the user control panel. I apologize if some of this is redundant.
I rechecked the ribbon cables for continuity - check good.
I have no more than .3V for any pin of P3, P4. (I have a hard time understanding why this is.)
On the user control panel, I get NO continuity at the socket or the ends of the cables when I test the buttons, when I test using the posts on the back side of the actual button I get continuity.
2 conditions that have me scratching my head - absence of the proper voltage at P4 (+5V) (MCB)
Lack of button continuity after the actual button. (user control board)
In response to your 2nd post today; I DO NOT get any LED lights no matter what I do with any buttons when the machine is powered.
I can't thank you enough for the help you are providing me, I really didn't think this would be so elusive.
Gary
Hi again Gary.
The lack of 5 V + or - at P4 is telling you there is a problem with your remanufactured MCB. It has to be there or just as you stated you will NOT get any display at all. The continuity on the ribbons also makes little sense unless the electrical conductor runs are bad in the ribbons. The can be damaged on the very end of the ribbon or broken inside the ribbon. You should use R x 10,000K Ohm for checking the ribbon runs and... take into account that your body resistance will show up on the meter IF you touch the leads. You may want to give the supplier of the MCB of the card a call and tell them you have no LED / LCD display at all or 5 V at P4 yet you have all the correct voltages off of the PCB transformer. It is only a matter of a resistor and a printed circuit electrical conductor run from the PCB transformer to P4. It sure sounds like either the resistor has failed or the printed circuit board electrical conductor run is open. With a ton of patience you can follw the run fromthe PCB transformer through the resistor to P4. Mind you there is also a set of diodes that convert the 15 Vac out of the PCB transformer to 15 V dc then that 15 VDC is dropped via a circuit resistor.
I am pretty much at the end of my rope here as it seems the Remanufactured MCB still has a problem. The touch/keypad issue may also be something that prevents dryer operation even after you have a properly working MCB installed. I have pretty much pulled out all the stops and gone beyond the service manual coverage of the MCB functions. I wish I could do more.
Kelly
Kelly,
I had a very lengthy and constructive conversation the the MCB reman co. He said it's not out of the question that I have NO +5V at pin 3 of P4 due to the fact that some of these MCB's require feedback from the keypads in order to provide the proper voltage(s) to P3, P4. He feels very strongly that is a keypad issue having a history of high failure rate. He said they are more than happy to recheck my reman board and fix or money back, my call.
At this point, as much as I hate to do it, I will have to order a keypad. Not much left to do.
I also wanted to thank you again for all of your time and effort - you have been extraordinarily helpful and very patient through this task as I decended into the bowels of this machine. I would recommend this service as great tool for my fellow DIY'er.
Thanks again.
Gary,
It really was a pleasure going thru this with you. I love a challenge especially when the person in the home has the skills to do what it usually takes a seasoned tech to accomplish. For me it is never about the money and when a person like yourself happens across the site it is just plain FUN on this end. My goal at FixYa is just pass along my knowledge and skills to help people. See this link:
http://blog.fixya.com/index.php/2010/05/...
I am so glad you actually made the call to the MCB source and that they also confirmed my comment that even with a good MCB the touch / keypad can still be the source of the original problem.
I sure would like to know what happens after you install the new touch / keypad. I.e it works or... your sending the MCB back to have it checked.
Just respond here and I will see it even though the problem listed on the site is cleared to a solution.
I have to also thank you for making the experience worth while in that you used your skills both technically and in print very well. That my friend is a very rare on line occurrance, so when a fella like you comes along it is nothing but sheer joy on this end. Thanks again.
Kelly
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Hello Gary,
Welcome to FixYa.
While I don`t know specifically the voltage readings of the points you are inquiring about, I don`t have a wiring diagram in front of me so I don`t even know exactly what these points pertain to.
I just wanted to throw the idea at you of checking the hi-limit thermal cut-out...if you haven`t already.
Based on your description it certainly sounds like a thermal fuse is open/faulty.
It`s located on the blower housing and accessed through the removable lower panel at the front. It looks like this...
You can either check it by way of ohming it out or jumping it out. It`s only $15 - $20 at most appliance parts vendors.
It is such a common thing I just want to make sure you aren`t overlooking it. If you`ve already been down this road please accept my apoligize.
Let me know if this is indeed any help to you.
macmarkus :)
What I would like to do is be able to test (via voltage I assume is best) the front panel control boards to verify that I am indeed getting power to it. I've performed test #5 for button and LED's. I get continuity at the posts of all buttons, but no continuity at the socket of the ribbon cable the services these buttons. I can send you "tech sheet" that came with the unit via email or whatever. I've already replaced the Machine Control Electronics board but that didn't fix the problem. I don't want to start replacing pieces as I can't afford that. Plus I like to find a logical reason for the problem.
Thank you
Gary
Hi Gary,
I am actually away all weekend and therefore only have limited access with my iphone, service is in & out. Something I never asked before was whether you've attempted entering the dryer self diagnostic or not ? It is entered via the + - buttons of the timed dry or more or less dry settings. There will be one above the other and in a back and forth sequence of +-+-+- should get you in. Once entered, all leds should illuminate ( if so the control is getting correct voltages ) from there you can press start and perform test of the components.
Unfortunately I don't have the means to receive any "pdf" on my iphone ( which is also why these post's are always squashed close together, sorry ) and even my email is at times delayed...depending on the service I get while travelling.
I'll watch for a reply in any case, hopefully you'll get to the bottom of the dilema.
Regards,
macmarkus :)
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Kenmore HE4 mod # 110.95088400 Ser #MS0101029
Intermittent operation, cycling between the three "End Of Cycle Signals", cycling between heat settings. Now dead front control panel, interior light works.
What I would like to do is be able to test (via voltage I assume is best) the front panel control boards to verify that I am indeed getting power to it. I've performed test #5 for button and LED's. I get continuity at the posts of all buttons, but no continuity at the socket of the ribbon cable the services these buttons. I can send you "tech sheet" that came with the unit via email or whatever. I've already replaced the Machine Control Electronics board but that didn't fix the problem. I don't want to start replacing pieces as I can't afford that. Plus I like to find a logical reason for the problem.
Thank you
Gary
Kelly,
I received my key pad yesterday and installed it last night. All is well. For kicks I reinstalled the old keypad just to make sure, dead. I considered reinstalling my old MCE to verify that it was still good, as I suspect it is, but thought it better not to as I'm not sure if the original MCE may have issues therefore causing failure of the keypad. At $200+ dollars I'm not willing to sacrifice the new keypad to satisfy my curiosity.
It's been a pleasure working with you, hope to talk again sometime.
Gary
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