I am having an absolutely unsolvable problem with my 2004 Supercharged V8 Sport. It started when a borrowed a trailer from work. After pulling it 45 miles I put my truck into reverse and everything started happening! Lights, buzzers, just chaos. I unplugged the trailer everything seemed fine except the zero point calibration skid control lights were on (VSC & ABS). I plugged in my code reader and it showed no codes. Apparently the back-up lights shorted from my plug to the trailer, no fuses blown.
Since I was on the sloped driveway, I opted to drive back in the morning with the trailer unplugged without doing the zero point calibration. After the uneventful trip back, I dropped off the trailer and parked. At noon I left for lunch and truck started fine. When I returned from lunch the truck wouldn’t start. With the key on, everything seemed fine. In the start position, nothing clicked, nothing happened. I called a coworker who brought a jump box, the truck started. I drove to the fleet shop, to check the battery or charge it. Turned it off, then tried to start and nothing happened just like before. Put the jumper on it, nothing.
I plugged in the code reader. No codes. No check engine light. The only thing showing were the skid control lights on the dash. Even though the code reader showed no codes, I cleared the codes and the truck started! I repeated the stop/start sequence a few times and everything was working except the battery charge light was now illuminated. I returned the next day with my extra relays and fuses. Checked everything, no bad anything. The alternator showed it was working by putting out 13.9 volts. I drove home and used the truck the next couple of weekends and everything was working, except the battery light was on.
I have an extra alternator. I removed the original one and took them both to have them tested. The original tested bad, the extra one tested good. Battery tests good too. Installed the extra one, the battery light stayed on! Re-tested the original and it tested good, damn O’Reilly’s. I tried to do the zero point calibration and it wouldn’t reset. I’ve had trouble with this before so I left it for another day.
So while I was scratching my head on the charging light, I continued driving it around until this weekend with the alternator still putting out 13.9 volts. Three times the truck would not start. Turn the key nothing. All three times the code reader shows no codes, but after clearing codes it starts first time.
What I have deduced for the charge light, that either the diode in the charging light circuit in the instrument panel is out or the body B4 ECU is faulty.
The no start no code can only be from the engine ECM. I have researched this and found that other Toyotas have had similar problems resulted while backing a trailer. But no one has a solution. Remember. I replaced all the affected relays. Checked or replaced every fuse that deals with gauges, trailers, brakes.
Any Ideas?

This sounds like a tough one..but the only thing you haven't mentioned is did you check all the connections, especially the ground wires from the battery to, chassis, engine, etc.?

I would suggest you check the Power/Ground wire from the battery terminal. And about the Zero point calibration, I had done that before, some more expensive scan tool can do the job. If your scan tool doesn't come with this function, if I remember correctly, you can use two metal pins to short certain 2 slots from the OBD2 connector, then ABS light and ESP light will flash and then go off. Just google how to do Zero point calibration. Good luck!

Could also be the starter solenoid. Contacts and plunger wear out and you get exactly the symptoms you described.

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Sounds like the starter. Try hitting it with a hammer next time it doesnt work just to be sure.

Buy a new starter. AM OK.

I've replaced 3 starters in my 2005 V6 4runner.

On the V6 the solenoid is built in the starter, and easily removed. You replace the whole starter. Banging a starter will work once or twice, but that's it.

I paid $90 for an AM starter at Amazon, and it's been working for two years. In my experience no starter for my 4runner has lasted more than 4 years - including the OEM (which I had rebuilt once - and lasted 1 year before failure).

You wrote " If it’s the starter solenoid, why does clearing the codes on my OBDII scanner allow the engine to start? ".. VERY STRANGE. ASK A DEALER.

So... you carry that OBDII scanner everywhere? My 2005 4runner has never thrown a code in 15 years and 150,000 miles. My 4runner was built by the Japanese in Japan. I live in the Bahamas and 4runners are imported direct from Japan by dealer.

on the v8, the starter is under the intake. not quite so easy to smack it...

Thanks to everyone that has replied so far. It’s a head scratcher for sure. I saw where someone had similar thing happen while backing a Tacoma, but never saw a solution.

@AuSeeker and @yao995
Yes checked all the connections and grounds. Replaced the alternator with one that tested good too.
I have done the zero point a lot. I have made a micro switch with leads to make it easier. I go through all the steps, but it never confirms with the flash.

@BagiMT and @Captsolo
This 4Runner only has 65,000 miles. If it’s the starter solenoid, why does clearing the codes on my OBDII scanner allow the engine to start?

@PowerpointPro
You’re kidding right? Do you know where the starter is placed on the 4.7 V8? If so then imagine a supercharger in place of the standard intake manifold. Read the answer above.

@nevada
Yep even harder to get to with the supercharger.

feels like the ECU issue, since you have to use a scanner to erase the code every time to start the engine. What if you lose the both side battery terminals and hold them together to hard reset the ECU?(can drain the capacitors). Hopefully, it will be a simple fix. Good luck! Keep us posted.

If I remember right their was a few who found such a problem in the fuse box. Lose fuses or stuck relays or dirty contacts.

what code is it throwing?

usually this sound like the crankshaft position sensor

usually a code p0345

what type of reader are you using?

I don't know, but it kind of sounds like whatever was wrong with the wiring in the trailer, it back fed power to something when you put it in reverse. I'm not sure what could be wrong for sure, but I'd be taking a look at the ECU and the stability control systems computer (sorry, forget at the moment the proper name). Also I'd take a look at the Park switch in the shift console, if for whatever reason the vehicle thinks it is in gear it won't engage the starter. Sorry, I don't know enough about the vehicle yet to make really educated guesses, maybe someone who knows it more intimately will chime in.

I had a similar issue last summer. Intermittently wouldn't start with no codes, no starter cranking sound and verified good battery/alternator.

It ended up in my case being a faulty fuse on the starting circuit (would need to look at the engine bay fuse box to be sure, but believe it was the EFI fuse). Fuse pin was loose. Once started the truck would operate normally. New fuse and it was good as new.

Thanks again for the reply's!

@riceandpho
No codes. I don’t remember the code reader brand, but it does ABS and OBDII. Never hasn’t worked and it doesn’t cause the CEL when plugged in.

@jermc10
My thoughts exactly on the feedback. Isn’t the shift switch because a “clear codes” allows it to start.

@NinjaOne & @Seasparrow
Most likely not a mechanical problem, like lose fuse or wire. Remember a “clear codes” allow it to start.

@yao995
My thoughts exactly on allowing the ECU to drain any stray stuff. I left the battery disconnected for a week, then discharged it by putting the two cable together. It has worked so far, but haven’t taken off on a cross county trip like I would have done before. Good call. The charge light is off too.

The VSC Trac and VSC Off lights still will not clear. When going through the zero point calibration procedure the confirmation blinking lights doesn’t occur. The lights go off, but come back on when the truck is moved. As I stated, I have had this happen before and after about 50 tries it finally took.

I have P0420/p0430 codes on my runner. My CEL/VSC/TRAC lights are on all the time..LOL...
Hope found the issue!