[FIXED] 2004 Toyota 4runner V6 no crank no start problem

About a year ago I have bought a car in Chile to travel around south america for a while. The car is 2004 Toyota 4runner V6 with automatic transmission, 365.000 km.

For the last week or so I am experiencing a problem with starting the car. Usually in the day the car starts just fine, ok sometimes it happens that it hesitates for a second or two, but it always starts. After I drive it, 15 minutes or 4 hours doesn't matter, I park it. Then after I get back to the car, it again doesn't matter for how long it has been sitting, sometimes it doesnt start. I put the key in, turn it and all the lights go on as normal, but then it doesn't start. It doesn't even make a sound, no click, nothing. The key just turns silently in the ignition. It always starts after few minutes, after I have played with fuses and relays for a while, but don't know if this really helped or not. It also always starts the next day. Once when it didn't work we have tried to jump start it connected with cables to another car but it did not start, so I guess it could not be the battery. The car has never died while running.
The battery is about two years old, and in those two years, the car did around 100.000 km. I did not have it checked, but everything else works fine – lights, radio, headights...
I have checked all the fuses, and could not find any blown. But I have discovered, that according to the drawing on the fuse box, some of the fuses don't correspond to the right power: DR\LOK is 15A (instead 20), EFI 15A(20), ETCS 20A(10) A\F HEATER 20A(15).
I also don't know if the black marks on the contact side of STA relay are normal – see picture.
The starter was rebuild 30.000 km ago, so I guess this should not be the issue either.
I did have a check engine light about 1500 km ago. After a scanner check I have changed spark plugs and everything was ok.
Now I am currently in Bolivia, and that's the urgent part A local guy came to check the car with a scanner (it was a small, cheap looking scanner) and could not connect to the car's computer. Afterwards he said I should go to the bigger garage to get it checked by a proper scanner so they can check the ECU, but that it would be expensive (160 $). Amongst the probable causes he listed (without checking the car at all): ECU (800 $), some senzors or some wires. Afterwards other guy came with better scanner, connected it with the car without problem. But the car always started so he did not get any errors on his scanner. Suggested I leave him the car for a day, so he can test it while it does not start.
I did not pay attention to the car imobillizer system, how it acts when this happens. It does have aftermarket alarm installed, but just for the function of remote control nothing else.
When I switch ignition to ON, the check engine light does come on, I also think I can hear the fuel pump working at the start.

But as I am in a country where you can't really trust local mechanics I am in a need of help. Where and how to start with the diagnosis, so I don't start throwing parts in to car which could be expensive and hard to get here, or with visiting to many local mecanics.
I must also mention that the environment here for the last 2-3 months is really dry – no rain. And the problem started to appear after spending time for the last month more or less in a desert, really dry, sandy and windy. Some of the time at a very high altitude – 4000 to 5000m (13.000 to 16.400 feet). Don't know if this has anything to do with it.
Oh, and of course I am not really a car guy ;( .

Because of my current location the situation is urgent and I would really appreciate your help. Thank you so much!

Hey Zverka! I see that you had the starter rebuilt recently, but this honestly sounds like a starter issue to me. There's a couple tests you can do to narrow down the possibilities.

The best thing would be to get access to the electrical connections at the starter, and use a test light on them when you can get it to not crank. There's two cables that attach to the starter, and both should make the test light shine brightly when the key is held in the Crank position. The starter is on the left side of the engine on the V6, so I believe your best option is to reach in through the drivers front wheel well.

The other option is to check the STA fuse, 7.5A #2, for power with the key in the Crank position. This fuse only gets power from the ignition switch in Crank, so it's a good indicator of ignition switch function. This test doesn't check EVERYTHING, just the ignition switch itself. I've attached the starting system wiring diagram for reference:

As Tyler posted above quite often starters can fail with the symptoms you describe, sometimes a good thump will give a get you home fix until the problem happens again. However that fact you don't hear any click at all would make me do a few extra checks, I would ask a some helper to work the starter while you listen to the starter relay (the small relay not the starter solenoid) if that isn't clicking then the fault lies in the control circuit from the ignition switch or the relay itself. If the car is an automatic it will also have an isolator switch operated by the gear selector that has to be considered.

I apologize for late answer.
You were right, it was a starter problem. The connection wire to the starter was loose, so sometimes the car started normally, other times not. it took 5 minutes of work and 3 USD to fix the problems.
Thanks!

Nice, thanks for letting us know! Calling this one [FIXED].