2004 Vectra 40KD microwave issue

[Vectra2020]

Hello,
Today the microwave stopped working, first thought was it was a breaker, or a GFI trip, checked that, all is OK. Unplugged the microwave, and ran an extension cord from another outlet, microwave works just fine, so no power to receptacle in the upper cabinet. I looked at the wiring diagram, and apparently there are two GFI's, one I located in the galley kitchen area, but I am unable to find the other one. Everything else works electrically, could it be by chance a faulty breaker?
Any info/help would b greatly appreciated, we are wintering in Victoria, and a convection/microwave is essential.
Cheers!

[Eagle5]

On page 6-6 of your Owner's Manual, it appears that the second Ground Fault Interrupter is located below the bathroom mirror in an exposed wall outlet. Of course, I assume that the main circuit breaker (page 6-4) for that 120 VAC outlet is not tripped, right?
Another thought would be if the Inverter is switched-on, but it has either its reset switch thrown, or one of its two circuit breakers popped (see page 6-4.)
In the meantime, you can get a nice 12 gauge grounded extension cord to keep your microwave running from a functional outlet until you get this all sorted out.
Good luck; Eagle5

[Morich]

No GFCI on this problem.
The first thing to do on looking for trouble is to find what is NOT the problem, so knwoing that most of the 110AC is okay can be a big clue as that cuts out most of the wiring questions.
I've done some markup of the drawings to cut out what you DON"T need to look at and leave only the needed items.

Since most things are working, we can skip checking the main breakers at the load center and move on to the inverter breakers.

A quick check of that breaker, flipping it off and back on to make sure it is not fooling you is often a good move.
Click these sni[s to get a better view or go direct here:
https://www.winnebago.com/Files/File...ire_147321.pdf



If that seems okay, some thought on the inverter itself may be needed. But since most of the RV is working, the inverter is likely on and not the problem as most of your items do work through it. Main inverter breaker likely okay!



That only leaves the 15 amp breaker on the right at the inverter panel and a pretty straight run to the microwave.
Not much way to spot where, so it may require pulling the covers on some of the connections shown to test for where it stops.

Any chance the microwave cord was simply loose at the wall?

Good luck on the bug hunt!!

[emiddleb]

Your microwave plugs into its own outlet in the cabinet to the left of the microwave. I'm sure you know this as you mentioned unplugging it and trying a separate power cord.

You have two GFIs on the coach. Each essentially handles one side... the one on the back shelf in the kitchen is for the passenger-side outlets, and the one at the base of the fridge on the front side is for the driver's side outlets. NEITHER one affects the outlet for the microwave.

The microwave outlet will run on any of the three power sources - shore, gen, and inverter.

There is a dedicated 120v circuit breaker on the panel of the bed frame. It's the furthest one to the right. As far as I can tell it's the only thing that should be in the way of getting power to the outlet, assuming all else is ok.

So I guess I'm suggesting either the breaker or the outlet has an issue.

(Verified on my RV... same make/model/year as yours.)

[Vectra2020]

Thank you all so much for all the help, did some more testing, got a voltage tester, and checked the microwave outlet, no power, then I took the bottom drawer out, and found the microwave wire, and there was power there. So, next step is to take out the MV, and trace the wire from there to the bottom cabinet, my guess is I should just replace the wire, fish another one in place.
Thank you all so much for the advice, it’s great to have such a forum as this, and such quick responses too!
Stay safe,
Cheers!

[Eagle5]

Hi again Vectra2000,
This is a fantastic diagnostic tool for this type of failure:
Klein Tools NCVT1P Voltage Tester, Non-Contact
With it, you can see anywhere in the line that either has voltage, or does not. It seems to me that it might just be a bad outlet and not the wire at all.
Thanks, Eagle5

[Vectra2020]

I actually bought a Klein tool, not sure which one, but it also came with a receptacle tester, that is how I determined the wiring fault, I am the second owner of this coach, looks like the original owner had replaced the factory MV with one manufactured in 2007, so I will need to pull this out and look at the suspect wiring.
Thank you so much for all your help, I will update this post when I solve this, for the time being I have an extension cord plugged into the MV.
Cheers!

[Eagle5]

Yes, the Klein Tools are an excellent value; accurate readings at a good price.
The tool above will detect voltage through the wiring insulation without metal-to-metal contact. Of course, you can also insert it into the hot side of the outlet to get a reading as well.

[Ray,IN]

I think eagle5 has the answer. The cheap 120VAC receptacles put in RV's just have a push-in connction, the wire is not even stripped first. That and normal road vibrations will loosen these weak connections.
Microwaves are normally on a separate circuit,without a GFCI receptacle; so since voltage is detected in the wire prior to the receptacle, but none at receptacle, it has to be the wire connections.

[Morich]

Traveling without full pc so I'm limited but fully agree that wire replacement is not likely as much as connections checked and one really bad point is the outlet.

[Vectra2020]

Hello, Forgot to mention that I did remove the MV receptacle and checked the wiring at the receptacle with the Klein tool, and there was no power. I also discovered the MV had a manufacturer date of 2007, my coach is a 2004, so it looks like the original owner replaced it at one time. I purchased the MH from the first owner in 2020. I noticed looking with a flashlight the wiring at the back wall had some black tape around it, so I suspect the issue is located there, means the MV needs to come out, and take a look at that suspicious connection. Cheers!

[Eagle5]

From what you are describing, it sounds like somebody might have used a displacement splice & electrical tape. If that is the case, that methodology is not allowed.
I hope that it is not presumptuous of me to say, but if indeed that wire has been spiced and simply insulated with tape, then the entire wire must be replaced. This is because all 120 VAC electrical needs to be double-insulated; for example:

1. Wire runs have insulation over the white & black wires, plus an insulating over-jacket; hence they are double-insulated.
2. Wire terminations to outlets need to be inside a box.
3. Wire nut splicing (to repair a broken wire) need to be located inside a junction box.

Because splicing require about 12" of extra wire on each end to safely terminate with wire nuts inside a junction box, they always become patches (require two junction boxes and a separate length of patch wire.)
Replacing the entire wire run is the best option.
Thanks, Eagle5

[madred]

I have the same problem with my 2005 Vectra. I checked all the same items as you and decided it is something to do with the wire from the breaker to the outlet for the microwave. I believe it runs under the cabinets and shower to the breaker box. My RV has a outlet below the the microwave that we do not use (mainly because my wife cannot reach it). I took the plug from the microwave and moved it to this outlit and it works great. I turned off the breaker for the microwave and placed tape over it so it is not easy to turn back on.