Odd “Lo dc” error on fridge

[dedmiston]

I’m camped with full hookups and everything seems to be working fine, but my fridge is complaining about low power.

I don’t know much about the converter/charger on this rig. This is the first coach I’ve owned that came prewired with an inverter and I didn’t need to install a new one to replace the converter. (Inverter is turned off since we’ve got 50a shore power at this camp.)

I noticed that the battery level was low this morning according to the solar control panel. It looked like it was turned off, so I turned it on this morning.

The level has been high all day, but the “Lo dc” came back on late this afternoon.

I’m stumped.

The first photo is from this morning. The second two are from just now.

 

[dedmiston]

Well, it’s a cloudy evening and the solar isn’t doing much anymore. I don’t know why that matters since we’re on shore power, but the batteries are down to 11.9 now and the fridge is showing Lo dc again. Everything else seems to be running fine (smart tv, appliances, Starlink, etc.), but the batteries don’t seem to be charging. This looks like more of a 12v problem and not a fridge problem.

It’s a head-scratcher. I’ve seen all sorts of power issues, but never with good shore power. And never just the 12v side.

 

[Carl n Susan]

Your propane/electric refer (I am assuming that is what you have) requires 12V at all times. Is the converter turned on? Is the Red Disconnect Key in the Convenience Center in the position where it can *NOT* be removed (or do you have a Giggy box and it is disconnected)?
I can't help with the inverter set up on your rig.

 

[dedmiston]

Hey Carl. Nope. The switch is in the right position. I just flipped it off and back on again and all the lights cycled off and back on.

We’ll see if that changes anything. The Lo dc error is gone but the batteries are still low. I’ll check again to see if they come back up this evening.

 

[Carl n Susan]

It seems your batteries are not charging. Here are step by step instructions for diagnosing a non-charging battery system.

The 12V flow from the converter to the batteries is pretty straight forward. All connections should have 13.5 +/- Volts if the converter is working.

• The converter is part of the power distribution panel -Ensure the CB for it is On
• There are Reverse Polarity Fuses on the converter which protect against connecting a battery backwards. - Ensure they are not blown.
• Check the output voltage at the converter. - it should be in the 13.5V DC range.
• Prior to the new Giggy Box (which replaces the Red Key) the power then runs to the Disconnect Switch in the Convenience Center. - Ensure the Red Key is in the position where it can *NOT* be removed. If removed, this interrupts the power charging the battery. The Disconnect Switch is not know to fail, but you can remove it to check there is power in and out of it just to be sure.
• The power next flows to the group of 50 amp self-resetting CBs behind the battery. We all know about the one that hiccups and interrupts the hydraulic system. That one also passes power to/from the converter and batteries. You want to check it and it's brother (it is in the current flow to the battery) to ensure there is 13.5V on *EACH* side of the CB.
• The last connection is the one from the 50 amp CBs to the batteries. Ensure you have clean connections and the cables are not corroded (watch out for internal corrosion under the shrink wrap).

Somewhere along this path there will be the problem. A simple VOM should find it. I hope this helps.

 

[daboom11]

You probably tried this but, did you turn the Fridge off & back on again? I have the same Fridge.

 

[dedmiston]

You probably tried this but, did you turn the Fridge off & back on again? I have the same Fridge.

LOL. Yep. It actually turned itself off when the voltage got too low.

We thought the converter had gone toes up since we got a good charge from solar but not from shore power. It turned out that three fuses had blown. I replaced them all and it charges great now.

We spent Friday-Wednesday up in Mariposa just outside Yosemite and had a good charge the whole time.

This was our first long-ish stay with just 30a power. We stayed at the Mariposa County Fairgrounds and it was beautiful there, but the only 50a FHU sites were in nasty dirt lots with mostly long term tenants. We opted for the big grassy lot that only had 30a power + water (no sewer).

One of our kiddos is a white water raft guide on the Merced and lives just outside Mariposa. This was a great spot to stay for visits and we'll definitely be back.

 

[Carl n Susan]

Nice looking spot!