My LE has twice "gone dead" in a fashion. All power is lost when this happens, lights do not work, clock needs reset, keyless entry inoperative and I have to use the key to unlock door to even get in. As I said just like a battery cable has been removed. After a short time everything returns to normal for no obvious reason.

Is there a cutoff relay somewhere in the Toyota wiring that could cause such a catastrophic shut down? I could not find anything like that on the diagrams for older 4R's but thought perhaps it might be on newer models. I had a remote start installed by the store that does all of them for the dealership and he said there is nothing that would kill all power in their install.

I am getting suspicious of some sort of battery issue but when I checked the voltage on the battery while everything was dead it read 12.8v which would be within normal range. There seems to be no corrosion on battery posts that is apparent but I will be cleaning and coating with Noalox or similar compound.

Any other suggestions are appreciated as I volunteer for American Red Cross Disaster Action Team and cannot afford to have an unreliable vehicle.

Thanks

Warranty? Have dealer look at it?

1. I'd be interested in what the dealer says about this.

2. Did you have the RS installed on your own, or did the installer do it through the dealer?

3. Regardless of what the RS installer said (I'd expect them to say that, btw), I'd give serious thought to having that RS uninstalled if you can't find another cause. Personally, I'd be very suspicious of this being the cause.

4. Also might want to look for rodent presence/damage.

Already been there, they have no idea unless they catch it actually happening which has been rare, that's why I hoped one of the very knowledgeable techs that check in on this site knew about any device in the circuits that could kill everything. I really do not think there is such a relay anywhere on the truck but thought to ask here as I do not have access to later model wiring diagrams. Usual trained idiots on the service writer area that are just there to sell service just fluffed it off and tried to blame my remote starter (they contracted), ham radio and HID lights. These fools were extremely suspicious of the ground wire I ran to the hatch for my 2 meter antenna. The radio was shut off both times when the issue occurred.

Thanks for the tips Philsey.

Again a possibility but have seen no activity at Decon station in garage or on sticky sheets other than a couple of bugs left from Fall.

1. I'd be interested in what the dealer says about this.

Basically if it isn't dead when it's sitting in our service bay we don't know what to do.
*to be fair, yours is the absolute worse kind of problem to find. And, unfortunately, with the ham, and the hids, you've given them ammo for fingerpointing.

2. Did you have the RS installed on your own, or did the installer do it through the dealer?

Contracted by dealer before delivery.

3. Regardless of what the RS installer said (I'd expect them to say that, btw), I'd give serious thought to having that RS uninstalled if you can't find another cause. Personally, I'd be very suspicious of this being the cause.

It's alway a possibility and I do not use it that often. May look into where the fuse is located first and get more drastic if problems get worse. It is rather nice to have though as it was below zeroF this morning.
* my rec in uninstalling it was strictly as a troubleshooting technique. If your problem stays, you know what it is not. Intermittent problems are THE worse. You gotta start somewhere man.

4. Also might want to look for rodent presence/damage.
* regardless, it's that time of the year, I'd give a good look around.

I used to work in a dealership and understand the difficulty in finding intermittent electrical glitches. And that was long before the trucks became the electronic wonders they are now.

Forgot to mention the first time it happened was shortly after I got it in June and none of the "suspicious" items were installed at that time.

The radio can be isolated in a matter of minutes as could the HID's.

I just kind of got a giggle about them questioning the ground strap around the hinge on the rear hatch. Hinges suck at carrying ground for RF.

I will be cleaning the bat terms and cables just to be sure but nothing seemed out of line with them. If things get worse I will begin to isolate the questionable items.

Mainly I was just hoping some one could tell me there is no "master disconnect relay" that would totally kill all the power to everything. Even the headlamps or parking lamps would not come on when the switch was put to on not auto. This would tend to point toward a battery or cable issue.

Some vehicles also need the hood grounded to assist Ham radio.

I would suspect the battery.When the condition is right the battery can temporarily internally short. Temporary shorted lead acid battery is fun to isolate.

He had 12.8v though.

Did you load test the battery too? Not that I’d expect you to really find an intermittent issue there, but to properly diagnose a battery issue it must be done.

this guy is knowledgeable:
Toyota 4Runner Forum - Largest 4Runner Forum - View Profile: rigtec @rigtec

2nd this approach. Until you can identify a single source for the issue, you're lost. Turn these off one at a time until you can identify the issue. I'm no electrical wizard, so I can't help you with possible causes, except that stock LE's don't do this unless there's a defect from the factory.

Here's a question from my ignorance: when high consumption aftermarket products are installed, do people put in breakers with the switches*, or are these "always on"?

Obviously, if you had a breaker it would be easy(-ier) to isolate the cause, but I presume that's not SOP.

*I guess I'm mixing terms here between switches, breakers, and fuses, but again I'm an ignoramus when it comes to electrical systems

+1 for this. In fact, this is the first place I'd suspect, or the primary hot/ground cabling somewhere. There aren't a lot of things that kill everything. Try the simple/obvious stuff first.

Let's page @rigtec .... and @BlackWorksInc

Battery was load tested at dealership with 2 different testers. After they did the first test with no issues shown the service writer had the mechanic get the "Toyota" battery tester which also found no error. I thlenbecame a game of pointing at which of the foreign items was causing the issue even though the same thing had happened once before any were put on the truck, other than the remote start which was predelivery through the dealership at their approved installer. Come to think of it, that may be a clue pointing at the remote starter.

All of the suspicious items are fused so it will only take a few minutes to isolate if the problem reappears. The key word being if since it has only happened twice in about 6 months. I suppose the correct word is when not if.