'01 SR5 Failed to Start

[cweiser]

I went to start my '01 SR5 2wd this morning, I heard a click and all electrical power went DEAD. I opened the fuse/relay box under the hood and jiggled some of the relays and it powered up. Turned the key and started just fine.
Could I have a relay failing? Which one?
I also wonder if a relay had become slightly unseated and by jiggling it I seated it properly... hmmm

 

[JayRolla]

I went to start my '01 SR5 2wd this morning, I heard a click and all electrical power went DEAD. I opened the fuse/relay box under the hood and jiggled some of the relays and it powered up. Turned the key and started just fine.
Could I have a relay failing? Which one?
I also wonder if a relay had become slightly unseated and by jiggling it I seated it properly... hmmm

It could be that easy. Sometimes a little tap can wake up a stuck relay. I would remove and reseat them all and make sure are wires are secure.

 

[IBallEngineer]

I went to start my '01 SR5 2wd this morning, I heard a click and all electrical power went DEAD. I opened the fuse/relay box under the hood and jiggled some of the relays and it powered up. Turned the key and started just fine.
Could I have a relay failing? Which one?
I also wonder if a relay had become slightly unseated and by jiggling it I seated it properly... hmmm

There is no single relay that would do that. It is FAR more likely to be the battery connection either at the fuse block, or at the battery. Also the main 120A fuse.

 

[cweiser]

Thanks, the battery's good and I don't tolerate any corrosion on the terminals... I'm pretty OCD about that. Doesn't the starter relay disable all accessory power when starting the engine?
Just weird the way it lost all accessory power until I opened the relay box.
The problem hasn't repeated itself... yet. Murphy's law, it'll wait till the worst possible time.

 

[IBallEngineer]

Thanks, the battery's good and I don't tolerate any corrosion on the terminals... I'm pretty OCD about that. Doesn't the starter relay disable all accessory power when starting the engine?
Just weird the way it lost all accessory power until I opened the relay box.
The problem hasn't repeated itself... yet. Murphy's law, it'll wait till the worst possible time.

No the starter relay isn't that smart. When the Ign switch is in the crank position, it sends power from the 30A AM2 fuse through the 7.5 Amp Start fuse to the ECM. The ECM then sends power to the trigger side of the of the Starter Relay. The "work" side of the relay is powered from the 120A ALT fuse, and the 40A AM1 fuse.

The ignition is sourced through TWO different fuses. AM2 and AM1. AM1 is further fused by the 120A ALT fuse. The white wire from the battery to the fuse block powers EVERYTHING except the starter motor. That wire and it's connections are where I'd look. I'm not just talking about visible corrosion, you need to SEE the wire and make sure the crimp is not compromised or full of corrosion UNDER the insulation.

http://tacoma.site40.net/4Runner_96-02_Repair&Wiring/techinfo.toyota.com/ileaf/ewdtmc2/ewdtmpdf/ewdsourc/2002/024runne/systemci/013sis.pdf

:blah:

 

[cweiser]

Great Info! Thank you,sir.