'90 4Runner Electrically Dead - Briefly
 

My '90 4Runner 280K miles sat for 6 weeks in the garage. My wife wanted to use it, so she charged battery (just to be sure) and climbed in to start it. The overhead light worked as she climbed in, the engine lights lit normally as she inserted the key, but as she rotated the key to start cranking, everything died electrically. No radio, no engine lights, no key buzzer, nothing.

I came home from work, get told that story - head over to look at it, climb in, and .... I have the same experience. The overhead light worked as I climbed in, the engine lights lit normally, but as I rotated the key to start cranking, everything died electrically. There was no detectable rotation of the engine - everything went black instantly.

I then went to the fuse box under the hood (passenger side, just aft of the battery) and banged on it a few times with my fist. This brought things back to life, but the process repeated the third time - all dead as the key is turned. I did it again, and on the fourth time, the engine starts and runs normally. It's working fine now.

Can anyone tell me what happened? Is there a relay or intermittent connection I need to look at? I'm reluctant to send the wife out with a car that may decide not to start.

Thanks.

There is a big main engine fuse in there. This is just a guess, but you know how sometimes a light bulb will burn out but as you unscrew it to replace it, it will come back on and last a few more days before it burns out again. MAYBE during your battery charging you reversed the polarity or something and blew the fuse, then your banging reconnected the fuse ends and welded them together. If it stops on you again that main fuse is the first place I'd check. Should be about a 80amp fuse.

Thanks, I'll take a look at that fuse - didn't realize there was one that big that handled everything. The wife hooked up the charger, and I suppose it's possible she hooked it incorrectly, but she said everything went smoothly during charging - the charge meter showed the right charge current and she didn't have to reverse the leads due to an error in connection.

My charger will automaticly reverse the polarity if connected wrong, but I think it might take a second or 2 for it to switch. I never hooked it up backwards to check, hehe. :laugh: Just a possiblity.

Another possibility is the cable connection to that fuse box is loose or the fuseable link coming off the battery is almost blown. To check the cable connection, you remove the fuse box from the fender and turn it upside down (or maybe you remove the whole top I can't remember now), there is a bolt or nut that holds the main power cable in place.

http://inlinethumb17.webshots.com/26...600x600Q85.jpg

The fuseable link just looks like a wire, but its a little smaller in size and its right off the battery on the positive side. Of course you want to pull the battery connections before messing with the fuse box.