Resolving F1 problem with electric Amana range

[ggibeau]

With the patience of a saint, our illustrious Samurai helped me through a variety of steps in order to trouble shoot an electric Amana range (ZRTSC8650WW) that was displaying the F-1 code.

Turned off power at the breaker box and pulled the range away from the wall in order to get to the sides. I then used a putty knife to help "pop" the clips holding the top down (this is a flat glass top stove). I then identified the wires leading to the temperature sensor and verified that the ohm reading was correct for room temperature (my reading was 1069 ohms which is in between the 1000-1100 spec as indicated by our illustrious leader). Once we verified that the problem was not the sensor, I did some further disassembly in order to get to the back of the ERC. Again, with the friendly coaching of “He Who Must Be Obeyed” ;-) I unplugged the touchpad and reapplied power to the stove in order to see if the F-1 code reappeared. After about 7 minutes of no F-1 code, we concluded it was NOT the ERC. At this point I was going to see if I could clean the contacts on the back of the touchpad, but it is basically glued down to the metal bracket that holds it in place and hence I was unable to get to the important bits. I did pop the cover on the ERC just to take a look, and I noticed a burn mark in the upper left corner of the glass display panel - not sure if this is important or not (see attached pic) . For grins, I plugged the touchpad ribbon cable back into the ERC, and after about 15 minutes, still no F-1 code. SO, I am not sure if it will reappear when we once again use the oven, or if in all the commotion I jiggled something back into place (but at least I now know how to take the top off and what to check).

[Samurai Appliance Repair Man]

[user=2915]ggibeau[/user] wrote:

At this point I was going to see if I could clean the contacts on the back of the touchpad, but it is basically glued down to the metal bracket that holds it in place and hence I was unable to get to the important bits.

Many of these membrane switch panels are just thin rectangles of plastic glued onto the panel and then they have a ribbon connector that threads through and connects to the ERC itself. It's that ribbon connector that I was asking you to disconnect. And there are no other contacts on the membrane panel that can be cleaned.

I did pop the cover on the ERC just to take a look, and I noticed a burn mark in the upper left corner of the glass display panel - not sure if this is important or not (see attached pic) .

Hard to see the burn mark in the picture you posted. Could you post a couple more with better focus and lighting?

For grins, I plugged the touchpad ribbon cable back into the ERC, and after about 15 minutes, still no F-1 code. SO, I am not sure if it will reappear when we once again use the oven, or if in all the commotion I jiggled something back into place (but at least I now know how to take the top off and what to check).

Ok, let's run the test for a longer time period. Leave it plugged in for the next 24 hours and see if the F1 re-appears. Then, unplug the touch panel and leave it that way for at least 24 hours.

[ggibeau]

I will attempt to get some better pictures.

I did reapply power to the stove this morning after reassembling it - and it worked fine. However, this evening my wife made some soup using just the stove top, not the oven, and the problems started again. First it starts switching between timer mode and time of day (with accompanying beep) and then it displayed the F-1 code until she touched the timer button - and it stopped. As of now, it is still acting normally - so I will give your suggestions a try.

Thanks again for all your help.

edit (3-16) - I did find out that my wife had used the oven yesterday morning with no problems. However, last night the infamous F1 and beeping reared its ugly head again and I had to unplug the stove so we could sleep. Will pull the ribbon cable for an extended period of time and see what happens. At leaset the burners will still work even if we can't use the oven ;-).

[Samurai Appliance Repair Man]

Anytime! And feel free to call me if you need to: 603-526-7129.

[ggibeau]

OK - I left the touchpad unplugged for 2 days - the stove top worked just fine, but obviously no way to use the oven. No F1 code - just the flashing clock (incorrect time of course). This morning, my wife wanted to bake some rolls, so I hooked the touchpad ribbon cable back up - she fired up the oven (while at the same time using the stove top) and the oven started heating. About 10 minutes into the operation, the display started jumping between TOD and the :00 of the timer setting, and then the infamous F1 code appeard along with the continually annoying beeps. Pressing any of the touchpad keeys do not make the F1 code go away. SO, I obviously need a new part of some type - the big question is it just the touch pad, or do I need a new ERC?

Any thoughts??

Thanks again,

George

p.s. - still need to get another picture of the ERC.

addendum - After the initial F1 this morning, things settled down and it has been acting normal since - I just think it is possessed ;-).

[kdog]

best check your oven sensor fist- should measure somewhere around 1000 ohms at room temp(this is a very general rule of thumb) and may be a problem somewhere in the wires between the control and the sensor(burnt,disconnected,loose etc).

[ggibeau]

I did measure it back to the plug on the ERC and it was 1069 ohms at room temp. However, I did not trace it all the way back to the temp probe to see if any of the junctions/connections were bad - it actually does not look like there are any more - but I will get a flashlight and point my eyes in that direction.

Thanks.

George

[Samurai Appliance Repair Man]

If you measured the sensor resistance from the sensor harness on the ERC, then the down-line connector is good, too. And your measurement is close enough to spec to call it good at room temp. It's possible that it could get flakey at higher temps and you could measure the sensor resistance the same way with the oven at a higher temperature. More details on sensors here:

http://fixitnow.com/2003/02/appliance-tip-of-day-oven-temperature.htm

But, I gotta tell ya, based on the results of test you just described above, I am absotootly certain that your touchpad membrane switch is the problem.

[ggibeau]

It has been working fine all day - both oven and stove top (although as soon as I type this, I am sure I am going to jinx it and the beeping will commence ;-)).

Anyway, thanks to all for the great suggestions. I think I will order a new membrane as my family is all coming in for a few days, and I really don't want the stove to conk out with 16 extra people staying here ;-).

Regards,

George