Norco Fridge Error E3

[4Papa]

I've a 2022 Cougar 25RDS with the 12V Norco fridge. On my last trip I've begun getting an E3 error on the display. Manual states E3 is a Low Voltage error, however no other 12V system in the trailer indicates an issue. The error happens intermittently whether on shore or battery power and will sometimes go away on its own. The 12V system has 400 watts of solar feeding a 2,000 watt Xantrex charger/inverter feeding a 300ah LifePo4 battery. All battery voltage indicators (Battery BMS, Victron shunt, Victron solar controller, In-command panel) say system voltage is 13.4 volts or higher.

Anyone else have this issue? Naturally the system is 7 months out of warranty (on a year and a half old trailer) and the dealer wants $200 just to diagnose. Thanks in advance for any help.

[chuckster57]

I would be pulling the fridge and verifying good solid connections. Maybe install some leads at the fridge connections and hook up a cheap volt meter to monitor the voltage. That way you can rule out either the fridge electronics or the feed.

[4Papa]

Sounds like the plan. Some online reports state RV manufacturers have been known to use wrong gauge wiring (>10-12awg) on runs to/from the battery. Were this the case you'd think the issue would have shown itself before now.

[JRTJH]

It's my understanding that the refrigerator "error codes" will set when a problem occurs and WILL NOT reset when the problem is resolved. The codes will only reset when power to the refrigerator is turned off and then turned back on (sort of "reboot the refrigerator).

So, let's suppose that a problem occurs in the middle of the night (when the battery is at its lowest charge after being used all evening) and suppose the refrigerator is operating AND the furnace kicks on. The "instantaneous draw" on a small gauge wire bundle that powers both the refrigerator AND the furnace, would show an "immediate voltage drop" causing the refrigerator to trigger a fault code because of the furnace fan motor starting up. That code would not "reset until the refrigerator is "rebooted", even though there was only a half second voltage drop.....

So, as you noted, if the wiring is "a wee bit too small" it may be allowing for a voltage drop which is not a problem with the refrigerator or with the furnace, but just the "installation wiring"...

How to fix it? Or better yet, how to confirm that is the issue: First, take note of what drains are occurring around the time you think the code is being set, if you can identify a specific sequence, then try to interrupt that sequence. As an example, if it's when the furnace kicks on, then don't use the furnace and see if the code no longer sets. Or, whatever you believe to be the potential cause, don't use whatever that might be...

If you can't identify anything, then possibly run a larger gauge wire with appropriate fuse in that wire, from the battery to the refrigerator 12 volt input terminals (bypassing all of the trailer wiring) and see if that resolves your code problem. If it does, then determine whether to isolate the refrigerator on its own 12 volt line or increase the side of the existing wiring run.... I'd think a new, isolated refrigerator circuit, probably from an unused 12 volt fuse position on the trailer power center would be the easiest to rewire...

[4Papa]

Good stuff. Thanks.

For the last 24 hours I've been running the fridge with no shore power and no other loads (besides whatever parasitic loads there might be that I can't control). So far no low voltage E3 errors with the fridge drawing 6-7 amps. I experimented with adding 12V loads, such as lights (10 full cabin LEDs & bathroom fan) and no error. The voltage did drop to the 11.7 range. The kicker test will be adding the furnace to the above. This I'll try today.

[4Papa]

So, the selling dealer has the unit and diagnosed the issue as, indeed, a low voltage condition due to factory wiring being insufficient to carry the load. As the camper is out of warranty by seven months, it will be my expense to repair, essentially replacing the wiring. Additionally, the dealer said the battery wiring "is a disaster with two battery disconnects and wiring from 8 gauge to 2 gauge back to 8 gauge.").

Here's the thing, I ordered this unit new (with the Solar 400i package). The only "modification" I made was replacing the two G27 lead-acid batteries with a 12V 300Ah LiFePo. I never touched the wiring so whatever the dealer's service department is saying is wrong with the wiring, is (like the Norco fridge wiring) a factory installation issue. All the changes needed for the change to lithium were with software.

Per the dealer's suggestion, I contacted Keystone customer service for a resolution. Stand by.

[German Shepherd Guy]

Check all your grounds. Over time a bit of fouling. That could lead to a "dirty dc voltage". which would kick off the fridge. After all the wiring was Ok when you first got it and used it? I would disconnect the main ground wire, usually to the frame i am thinking, and clean with sand paper and the re-connect. It would be an easy thing to do, would cost you only the time, and it very well could work. If that didn't do it I would trace the ground right at the fridge and clean that. Worth a shot I think/

Not so sure I would trust the "expert" technician at your dealers.

[4Papa]

You are right. There was not an issue with low voltage errors for the whole first season of use and most of this one with nothing changed as far as the electrical system (The unit is a 2022). If Keystone doesn't pay for the correction, I will retrieve from dealer and troubleshoot myself. Thanks for the reply!

[4Papa]

Would the ground wire to the 12V fridge typically be located at the fridge or elsewhere, such as the converter?

[chuckster57]

If the fridge is on its own 12V circuit, the ground will be at the ground bar located in the fuse panel.