I recently got a dometic 50 fridge. I found an old agm battery that I used for fishing that I placed in the back. It is a 12 volt, 55 amp hour battery.

I have been plugging in both the fridge and a noco battery charger (g7200) at night so that the fridge gets power from the DC while the noco charged up the battery.

Before that, I was using the stock inverter to power the Noco charger to charge the battery while it runs the fridge. If I drove it for an 30 mins, it would charge the battery from 50 percent to 70 percent. ( I used a wireless battery monitor)

At any rate, I was thinking what if I ran a separate inverter plugged into the cig port in the back to run the Fridge while I use the stock inverter for the NOCO so when I notice the battery need to be charge, I can activate the stock inverter.

do you think that this will be too much draining on the alternator?

side note, I can run the fridge for 3 days on the 55 amp hour which is good to know

Has anyone confirmed that this modification works? Id like 400W all the time as well. I have a laptop with 150W PS and I cant charge it while driving around. I hate buying another inverter since the factory one is capable and already there.

I found powering an inverter from a 12v outlet generally tripped off because as someone said, too much voltage drop to the outlet.

This thread, last pic, shows what I did to get reliable power.

Using Oxygen (O2) Concentrator in T4R

Hi Josh,
Thanks for adding your update as I am researching this issue too for my 2017 SR5
hungryhawk

are you sure? i was doing the math at 110 volts and 400 watts, that is about 3.3 amps and the alternator has to put out at least 75 amps wouldn't it? doesn't seem like much,,and on top of that,, that is at a full 400 watts,, most things you plug into it don't take that many watts. laptops and stuff,,, ( i am assuming

110V at 400W is 3.6A

BUT

12V at 400W is 33.3A

The invertor probably draws more than that at full output due to inefficencies in the conversion. IOW it may take 500W of actual power to crank out 400W of useable power.

That is why the invertor fuse is 80A

Good post. We can assume 10% loss for conversation efficiency, so it's likely closer to 37 amps on the DC side to make 400 AC watts.

Inverter fusing at near double is likely to help combat losses from line resistance and surge currents.

Has anyone seen a mod where they changed the 400w/100w switch on the dash to On/Off switch? So when you turn the car on it automatically comes on and turns off automatically when you shut the car off.
I have searched for about a week and have been unable to find anything on this.

This might be of interest to some.

https://www.ktjo4x4.com/4runner-power-outlet-2014

Cheers!

Interesting thread. I have no reason to change the outlet on my ‘18 SR5 because I don’t use the inverter while driving.

I do use the inverter mainly for routine vacuuming of my rig. I use a medium size Shop Vac. Beats having to run approximately 75’ of extension cord; I just keep a 10’ outdoor cord with the vac so I have enough to run around both sides of the truck.

I don’t know the amperage of my vac, but it does kick off at least once per session, sometimes more. It only requires switching the dash switch off then on to reset and I continue, but it’s a pain as it seems to always do this when I’m on the opposite side of the switch. Probably caused by the motor straining when vacuuming tight places that cause blockage to the hose, thus exceeding 400W.

this is what my dual battery setup is like. my battery and dc-dc charger is in one box as shown here on my setup. all i have to do is connect my fridge to the box and it's always on all the time whether i use the car or not.

https://www.youtube.com/watch?v=ZbVtZvK-f9s

I can't tell what i'd need from that site to just use my original outlets at 400w. I emailed them. I'm thinking i just need the 2 wiring harnesses and no outlets.. but do i need a longer cable for the rear outlet?

After I saw this post i started to research their 400w harness also. But i stumbled across this site. Apparently they're banned on the Tacoma site due to seller issues.

BUYER BEWARE: 2nd & 3rd Gen Tacoma In-Cab 120vAC 400W Anytime Power Outlet | Tacoma World

Thanks Josh_357 this worked. I found the writing a little hard to visualize, if anyone else does also here is my take:

1. To start you only need to remove the ac/dc panel in the rear. Use a plastic pry tool and pry from the bottom. rest it out of the way

2. there are two white connector plugs in the inverter. unplug the right one or the one with all the wires in it. I found unplugging it gave me more room to solder.

3. Find the black wire in the plug. for me it was in the bottom right. cut the black wire leaving as much of the wire dangling out of the back of the white connector. I did not undo the wire loom. I just cut it at the tape.

4. strip and crimp or solder to another wire, I soldered and shrink wrapped a 7" piece of wire to it. on the other end I crimped it with a ring heat shrink wire connector.

5. Remove the 10mm bold under the inverter, add ring end and replace bolt. Not a lot of room to work here, I used a little ratchet and an extender.

All done.

I ordered the KTJO4x4 harness to make my outlets 400w all the time and it was shipped no problem. And, the install went smooth.