Old Norcold Fridge - Died Suddenly

[KendallP]

2-way fridge. Lights on the eyebrow don't light and there's no ignitor activity nor can I hear valves for LP and 120V also does not cool. There's proper DC voltage on either side of the 3A fuse. Hard to imagine the eyebrow rocker switch went out suddenly for both AC and DC and since I don't have a circuit board tester in my toolbox, I'm guessing I may be out of easy diagnostic options and my next move may be to see what a new board can do. Or am I wrong? (He waits for his cantankerous, adopted gramps, Mexicowanderer to gripe at him if he doesn't run every possible diagnostic at his disposal... and some that aren't.)

This is the one book I don't have in my packet from the original owners and I can't read the model number on the placard. It's an '86 Winnebago, so my research seems to point to an 8310 EG2 or 838 EG2 ("2" for 2 way, i.e. LP and 120V.) I don't know what the differences between these 2 are, but either model uses the same Dinosaur board. Below are some photos if anyone has knowledge enough to agree or disagree with this assessment.

If correct, it appears that the recall was performed as the board does not appear to be the original. These folks performed maintenance well before recommended intervals, so it would be reasonable to believe that they had the recall addressed as well. There are also little plastic buttons on the far outsides of the eybrow which is supposed to be another indication. AND... I don't see that there is AC power inside the eyebrow, which was supposed to be the fire hazard that caused the recall. Hope I'm right.

First photo is a shot of an original board from Dinosaur's page and below that... my current board. Then the rest of the unit in case any of you can recognize it that way...









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[KendallP]

It seems highly likely that the power wire is there to run the heater wire. Just switching a ground is not going to supply it power without power coming in to the other side.

The door switch appears to switch the ground side of the interior light and possibly the heater wire, but I don't recall for sure.

So I definitely do have both ground and positive in there.

Next I will bypass the switch to power up the heater wire and see what happens. However, I wouldn't think it would do anything with the eyebrow as the unit is supposed to run without power to said heater wire.
.

[KendallP]

MEXICOWANDERER wrote:
Hint:

If you have power at any of these wires but the power dies when the wires are connected together as Mr. Rainer, instructs, there is a problem with the feed wire to source of power.

Connecting the power wire to what wire?

Obviously it will "die" if connected to a ground wire, i.e. short circuit.

[KendallP]

dougrainer wrote:
There is no ground, or there is no positive. I never had to check. BUT, there will not be BOTH. You NEVER need Pos and Neg thru this type switch. You are only routing the wires together. That is why I stated, connect all at the same time and the Eyebrow may light up. IF NOT, then the rear board is bad. Doug

OK, well then something must be screwy because I definitely have a positive and I definitely have a ground in there. I tested the positive by running it to another known ground. With the red of my meter on the wire and the black on the known ground, it shows a positive 12v and a negative 12v if I reverse the leads on the meter.

Also... I discovered that I have a ground in there by accident, i.e. I put the known positive to a wire and got a spark, i.e. short circuit. Killed the 3A fuse. Fortunately I had bought more. This is the wire that I connected by bypassing the rocker switch.

So by jumping the known ground with another wire of the same color, I get 12v to the interior light.

Now... when you had said "light," I thought you meant interior light. Nothing I have done has yet given me eyebrow power nor power to the valve and ignitor.

Based on what you're telling me, it sounds as though my jump of the ground should have lit up the eyebrow. Do I have that right?

Also...

I have discovered that I have an issue with high DC voltage with the generator running. Makes me wonder if that wouldn't kill the board.

Even with all breakers off, i.e. the converter should be off, I get around 15.7v to the board. This at no more than 63 cycles and about 127v AC down to 58 cycles (heavy load) and 115v AC. Very perplexing.

On shore power, a flip of one breaker will kill the charging power to the batteries and kill the converter power to the house. 6300 series converter.

[MEXICOWANDERER]

Hint:

If you have power at any of these wires but the power dies when the wires are connected together as Mr. Rainer, instructs, there is a problem with the feed wire to source of power.

[dougrainer]

There is no ground, or there is no positive. I never had to check. BUT, there will not be BOTH. You NEVER need Pos and Neg thru this type switch. You are only routing the wires together. That is why I stated, connect all at the same time and the Eyebrow may light up. IF NOT, then the rear board is bad. Doug

[KendallP]

dougrainer wrote:
GOOD question. I think there are 6 wires to the switch. Maybe 5. I no longer have a schematic for that 30 year old refer. GOOD news is, you can connect all together as all it does is jump power to the board and the Hi humidity Heater strip. Find the HOT 12 volt wire. Then take each of the other wires one at a time and connect to the 12 volt wire. When you find the one that activates the eyebrow panel jut jump those 2 together. I would not worry bout trying to activate the Hi Humidity heat strip. Doug

Completely agree about the humidity strip. That's an unnecessary luxury... especially for a family that does so much boondocking. We like to go as many days without a noisy generator as we can and every amp counts. Would rather leave that switch alone than I would forget to reset it.

That said, if I ever get the bulb socket fixed, I definitely would want to switch the light off when we store the rig with the fridge doors open.

Speaking of light socket...

Yes. 5 wires to the switch. Looking from the front of the switch, the center right tab is unused.

Unfortunately, when I took the whole metal panel away from the fridge, 2 wires popped off, though I'm fairly certain I saw which where which beforehand. When viewed from the front, the came from the left center and top left tabs. I think the left center was the (+) lead and the top left went to the heater strip.

The bottom left, I believe, is the (-) wire that goes to or comes from the light socket.

I couldn't seem to get power to the light socket just using the switch, though I want to retest that. I WAS able to get power to it once I figured out it was the (-) side that was being switched.

The light socket is pretty beat. The bulb works in other sockets, but not in that socket, 12v on or no. So I suppose I still don't know if I have current to that socket or just 12v after I jumped the wires.

So my question to you now is...

If I was able to bypass the switch and power up the socket, should I have seen power to the eyebrow and should the unit have powered up?

'cuz nunna' that happened.

Or is there another wire that I should jump for that. I believe there are 3 coming through the fridge wall to the switch/heater assembly. One is (+), one (-) and I believe the 3rd may be neither at present. However, I don't recall trying to see what happens if I put the meter to that wire with either the (+) or (-) wires.

[dougrainer]

KendallP wrote:
Doug,

How do I hotwire/bypass tthatswitch to test?

GOOD question. I think there are 6 wires to the switch. Maybe 5. I no longer have a schematic for that 30 year old refer. GOOD news is, you can connect all together as all it does is jump power to the board and the Hi humidity Heater strip. Find the HOT 12 volt wire. Then take each of the other wires one at a time and connect to the 12 volt wire. When you find the one that activates the eyebrow panel jut jump those 2 together. I would not worry bout trying to activate the Hi Humidity heat strip. Doug

[KendallP]

Doug,

How do I hotwire/bypass tthatswitch to test?

[KendallP]

dougrainer wrote:
...IF the interior light comes ON in either position the switch is sending power to the board. IF the light comes ON, then odds are it is the board. Doug

Yeah, Bigfootford was good enough to apprise me of your credentials. Glad to have you aboard the thread!

Well... the light has been out for ages. And I don't recall if I tried changing and gave up or just never changed it out. We've never gone wanting for it, but it would be nice to have, actually.

But given I have power to the switches... the light should come on in at least one door switch position... so long as there is not too much corrosion in the socket and/or socket assembly. Sure worth a try, though. If I don't get light, then my results will be inconclusive, but if I do get light, then it sounds like the board is likely toast.

I'll go back to the yard in the morning and try that.

[dougrainer]

KendallP wrote:
OK. That weird voltage situation appears to be solved. I had the 6300 series converter running with the bank unhooked. It was sending 7.5v to the board that way. Weird since that converter has a separate charging circuit, but we all know there are better converters.

Hooked it back up and I get about 13.5 at the board and about 13.1 at that humidity switch.

Doug,

Boards go too, right? What are the odds it's the humidity switch or something other than the board?

20 years ago I replaced dozens of the Humidity switches for corrosion failure causing the refer to not power up. IF the interior light comes ON in either position the switch is sending power to the board. IF the light comes ON, then odds are it is the board. Doug

[KendallP]

OK. That weird voltage situation appears to be solved. I had the 6300 series converter running with the bank unhooked. It was sending 7.5v to the board that way. Weird since that converter has a separate charging circuit, but we all know there are better converters.

Hooked it back up and I get about 13.5 at the board and about 13.1 at that humidity switch.

Doug,

Boards go too, right? What are the odds it's the humidity switch or something other than the board?

[KendallP]

dougrainer wrote:

KendallP wrote:
Hmmm. My unit doesn't have a switch on the board... nor does the board look like any of those. Looks like theboard I've seen for the 8310 and 838. My hhumidity switch is 3 position. Markings read from top to bottom...

Normal Operation
Storage (Light Off)
High Humidity

Refer will not power up unless in either Normal or High Humidity. The corrosion when you pull the switch is usually obvious. Doug

Wasn't bad, but couldbe better. Playaround with em and nothing. And board contacts were squeaky clean.

Now how 'bout this...

With light switch in the "door open" position, between lower left 3 position switch wire and either side of light switch contacts, I get 40v AC . ... AND 18v DC. That doesn't seem good.

[dougrainer]

KendallP wrote:
Hmmm. My unit doesn't have a switch on the board... nor does the board look like any of those. Looks like theboard I've seen for the 8310 and 838. My hhumidity switch is 3 position. Markings read from top to bottom...

Normal Operation
Storage (Light Off)
High Humidity

Refer will not power up unless in either Normal or High Humidity. The corrosion when you pull the switch is usually obvious. Doug

[KendallP]

Hmmm. My unit doesn't have a switch on the board... nor does the board look like any of those. Looks like theboard I've seen for the 8310 and 838. My hhumidity switch is 3 position. Markings read from top to bottom...

Normal Operation
Storage (Light Off)
High Humidity