Power in bed's rear AC plug won't stay on

Until it’s not. I’m glad your fridge works for you, maybe it will work for the OP too, but don’t give bad advice.

Each fridge is different and will have slightly different power requirements. My fridge idles at about 1A and as soon as the compressor kicks on it’s pulls an average of 6-7A.

That amp draw is why DC plugs that run to the bed are 10AWG and protected by a 15A fuse and why 400w can be pretty useless.

 

As others have said there is a mod for that. Beware that the reason it limits the plug to 100 watts is because the alternator can’t put out enough amperage while running everything else like headlights, ignition, blowers, A/C, etc. The mod could be a net drain on the battery. Chances are that you won’t run everything at the same time but it could happen.

I have used mine to keep a crockpot running on warm. It was wrapped in towels in a cooler in December as a drive 2 hours to a family Christmas party. The soup was hot when we arrived. In high it tripped the breaker.

 

6A-7A? Holy shit, what fridge do you have? A deep freezer?

Only reason I run 10 gauge is because of voltage drop. Most fridges have a battery protector built in and will cut off after the battery drops below a certain voltage. The longer a run of wire, the more voltage drop under load. Too thin a wire and the fridge will cut off prematurely.

I had my Dometic fridge on 14 gauge for the longest time until I realized the fridge would cut off prematurely during a longer trip due to the aforementioned reasons.


See quotes below.

 

ARB Element.

Good point about the voltage drop. I think I saw a 16AWG would lose about 10% at 25 feet or so

 

Does the bed out let harness need to be plugged in, in order for the inverter to work with 400w any time outlet installed in the cab ? Outlet in bed is blocked and was just going to unplug it from the harshness .

 

I have a Snomaster fridge that has an optional power cable with an Anderson plug. I ended up installing an Off-Grid dual battery system, and then I've run the power cable back to my fridge off of the auxiliary battery. Even if you don't have an auxiliary battery, you can still connect your fridge directly to the starter battery and avoid using any inverter.

An Anderson plus makes for a nice, solid connection that won't come loose like a 12-volt plug can. If your fridge manufacturer doesn't have a power cable with an Anderson plug as an option, you can still make your own. This is the plug that I bought that attaches to the battery by ring terminals and has an inline 50 amp fuse.

This is one of my posts about my install of the dual battery.

I hope that helps...

 

Easy to run a extra outlet

 

I had a similar problem and decided to stick with ice. That being said, you lose some efficiency and power converting DC to AC. Then you plug in an AC/DC converter and you lose more power. Direct tie in the batter a la Dometic seemed the wiser choice.