Whirlpool Gas Oven Mod. WFG510S0AS2, Ser. R44373042 Oven & Broiler NF

[BSers]

Greetings, Gurus,

Over the last six months or so, the oven has randomly taken between 2 and 10 attempts to turn on and heat up.  Now we're getting nuthin.  Broiler same way.  No life signs or sounds, no click, no whoosh, no gas smell.  Stovetop igniters work fine.  Incidentally, back when it did work, it wouldn't let us decrease the oven temp from the default 350...though it did let us increase the temp.

I'm thinking control board?  Can someone confirm before I plunk down the big bux (and where's the most economical parts source?  Quick search turned up $560...jeezus)

What's the warranty on Whirlpool?  We bought this stove in 2018.

Thanks in advance for any wisdom!

Cheers,
Geoff

[BSers]

Slight correction on my "no life signs" statement: actually, when you press Start you do hear a small "click" from the control panel itself, but nothing down below.

[Vance R]

This range has a separate spark module for the oven.  Since bake and broil are having issues need to check for voltage at dsi board ( range spark module).  Check for 120 vac at J1-6  to J1-4 for bake and J1-7 to J1-4 for broil.

[BSers]

Thanks for that, Vance.  So the part labeled 15 in the schematic below is just a spark controller for the oven?  If so, where is the one for the stove (which seems to work fine)?

https://www.fix.com/models/range/whirlpool/id876657/wfg510s0as2/section7178713/control-panel-parts/

[Vance R]

Number 5 is for the oven, 15 is for the cooktop.

 

[BSers]

Roger that, thanks.

[BSers]

Hi again, Vance,

Okay, I've got 120vac between both J4-J6 when Bake is activated, and J4-J7 when Broil is on.  What does that tell me?

Thanks,

Geoff

[Vance R]

3 hours ago, BSers said:

What does that tell me?

That the main board is sending power to the oven spark module and rules out the main board as a problem for oven ignition. 

Next watch the ignitor electrodes to see if they arc when first calling for heat. Should be 2 or 3 arcs. If no arc, ohm out the gas valve from the spark module  J1 pins 1 to 2 and 2 to 3, should be around 216 ohms. If there is an open coil move down to the valve and repeat the ohm test. 

[BSers]

I'm onnit...

[BSers]

Took me a day to scare up a digital meter (did the first test with a simple on-off tester).

Ohm test:

No arcs in either Bake or Broil

J1-2 192.8 ohms

J2-3 174.1 ohms

When you say "open coil", do you mean complete ("1") resistance?  If so, I guess getting the above figures means we don't have an open coil, right?  What does it mean that we're getting lower ohm numbers than you specified?

Standing by for interp and next steps.

Thanks Vance,

Geoff

[Vance R]

3 hours ago, BSers said:

When you say "open coil", do you mean complete ("1") resistance? 

or OL depending on your meter. Basically whatever the meter show when the probes are not touch anything.

 

3 hours ago, BSers said:

If so, I guess getting the above figures means we don't have an open coil, right?  What does it mean that we're getting lower ohm numbers than you specified?

The spec is 216 ohm plus or minus 30 ohms. so we are close in values, 174.1 is low, but i would think it should still try to arc.

Next need to verify proper polarity and ground at the outlet. 

DSI ignition use the chassis to complete the return path of the high voltage arc. Remove the module to inspect the grounding pad is clean and reinstall making sure that screw is tight. The burner tube usually require cleaning at the grounding location use emery cloth to clean the tube and cabinet. Same drill as the module, mounting screw needs to be tight.

Then you can check for dc voltage at the coils at start of ignition. Should be 8 to18 volts dc for at least moment

[BSers]

Okay, we're getting into some territory exceeding my understanding...this "module"...is that the entire circuit board with the J-series spark circuits?  Or a different item?  Are the "grounding locations" of the burner tube what's identified as Parts #21 on the exploded view? https://www.fix.com/models/range/whirlpool/id876657/wfg510s0as2/section7178714/manifold-parts/

So, what would make both the bake and the broil cease to light concurrently?  Or is it just coincidence?

Thanks for your patience with a layman.  I know just enough about this stuff to be dangerous...

[Vance R]

26 minutes ago, BSers said:

this "module"...is that the entire circuit board with the J-series spark circuits?  Or a different item? 

Referring to the parts diagram,  item #5 and where you made your measurement of J4 pins. 

 

27 minutes ago, BSers said:

Are the "grounding locations" of the burner tube

Basically this where the burner tubes are mounted to the chassis with screws. connection have to be clean and tight

 

32 minutes ago, BSers said:

So, what would make both the bake and the broil cease to light concurrently?  Or is it just coincidence?

At the moment no idea.

[BSers]

Voila!  Must have been surface corrosion on the circuit board ground plate, though it sure looked shiny and pristine pre-sanding.  What confused me about the "module" term is that the diagram calls both #5 and #15 "modules", yet I couldn't see any part in there that looked like #15.  Both oven and broiler fire up fine now, with 4 tests apiece.

I still have the separate problem of not being able to toggle the oven temp down from the default 350, but the plenum in the "down" button doesn't feel right (no click), so I'm thinking it would take wholesale replacement of the control board, which isn't maybe worth it for the price.  I think we'll live with 350+ on the oven.

Thanks, Vance.  Appreciate you hangin' in there with me.