Microwave light not working

[eyedocbob]

I've got a Kenmore built-in Microwave that's about 8 yrs. old. The other day the lights underneath that light the range top quit working. The bulbs looked shot so I bought some replacements but those don't work either. I tested the voltage and the sockets seem to be getting power (~104V). Everything else works fine. The new bulbs check out fine. Is there possibly a fuse somewhere? Any ideas?
Thanks in advance!

[Dan O.]

Model number?

I've got a Kenmore built-in Microwave

Which exact unit?? Posting its model number (as written on the appliance's model and serial number identification tag - not on the owner's manual, etc.) would answer that. You can find tips for locating the identification tag on your appliances in the 'Repair Parts' section of my web site linked below.

I bought some replacement [bulbs] but those don't work either. I tested the voltage and the sockets seem to be getting power (~104V). The new bulbs check out fine. Is there possibly a fuse somewhere?

There are not usually any fuses for the illumination lights but without knowing the exact model of appliance in question, I couldn't say for sure. I can tell you that if there was a fuse for the lights, it would prevent power from getting to the light sockets as well, so that scenario seems unlikely if there really is power there.

Any ideas?

I can only think of three possibilities; 1. the bulb is not making proper contact with the socket. 2. the bulb is defective or 3. your power readings are erroneous in which case the problem may be in the circuitry of the microwave oven.

JMO

Dan O.
www.Appliance411.com
The Appliance Information Site
=D~~~~~~

[eyedocbob]

Thanks for your reply.
I checked the light sockets and even pried out on the contacts a little but still no go. I base my assumption that the light bulbs are ok on the fact I got little resistance itha VOM. It's possible something is messed up in the circuitry as I think my wife was cleaning around the area before this happened.
The model # is: 721.67601790 Mfg 4/97

[Phelps]

If you are getting voltage (104 should be okay) it has to work. Did you use bulbs where the glass bottoms out on the rim of the socket, which then doesn't allow the center of the bulb to contact that tang in the middle of the socket?

HOW did you test the socket? Did you put one probe on that center tang and the other probe on the socket edge? If so..good. But if you put the one test probe of yor voltmeter on the center tang and then put your other probe to some other ground...not good.

[Dan O.]

I checked the light sockets and even pried out on the contacts a little but still no go.

Did you double check your power readings???

It's possible something is messed up in the circuitry

If that was the case than you should NOT be getting power at the socket.

The model # is: 721.67601790

I'm afraid that is a LG made unit that I'm not familiar with at all. I also do not have access to its wiring diagram to see what might be in the circuit to the lights.

I know on many GE OTR models, if you change the light bulb without disconnecting the micro's power first, the electronic circuit board for the light controller can very easily be damaged. I don't know if LG's design is that bad nor whether cleaning in the area could cause a similar fate. Sorry.

Dan O.
www.Appliance411.com
The Appliance Information Site
=D~~~~~~

[HayZee518]

check the bulbs again. if they are bayonet base maybe the lugs are offset to go in one way. most have lugs 180 degree opposite each other.

[eyedocbob]

Sorry it's taken me awhile to get back on this but other things...
I double checked the voltage and am getting a voltage reading (~108) regardless of whether the light is turned on or off. Something tells me that should not be. Oh well, maybe I can figure out another way to light the range top.

[Phelps]

This is a good one, if I ever heard one? What kind of voltmeter are you using, and do you have it set to 250 volts? What does it say when you put it in the slots of an outlet? *IF* you are testing correct, the bulbs have to work if the sockets are not ruined somehow through previous abuse of some sort. This is truly a weird one.

[eyedocbob]

I am using a digital auto-range voltmeter. Will re-test the bulbs.

[Phelps]

eyedocbob,

You still around? Curious minds need to know.

[eyedocbob]

Yea, I'm still here. Still haven't figured it out.
I double checked the bulbs in another socket - they work fine.
Unless it's just something in particular about that brand..
I dunno...

[Phelps]

HOW did you test for voltage in the sockets, exactly?

[eyedocbob]

Put one lead on the center/bottom contact and the other on the side being careful not to to touch. I did this on both sockets. I also tested at the connector where it comes apart to remove the bottom panel. I am going to get another bulb today to see if it make any difference.

[Phelps]

You did it correct then. If you had said that you were getting normal voltage between that center socket tang and some metal somewhere else...then, in theory, you could have lost your ground in the area of the socket.

It sure is weird though that you said that those bulbs worked elsewhere? This is really a good one. SOMEthing must be happening in those sockets that aren't allowing either the center or sides to make contact.