Intermittent no electrical power
 

Hi all,
I have a 2006 Ranger FX4 Level II (4x4, 4.0LT). I've had an intermittent problem where when I turn the key to crank, I'll get like half a second of crank and then nothing (no solenoid clicking either). I'll release the key and try again, and it usually starts on the 2nd or 3rd time. But a few times I can't get it started for a long time. I'll leave it alone for a little while and try it again and it starts right up. Yesterday when I tried to leave for work I couldn't get it started at all in the morning. It was basically completely dead. No radio, no dome light, no headlights. And no dash lights except for the anti-theft icon which was lit red. I tried moving the key in different ways, tried moving the battery cables under the hood. Nothing did anything. Eventually I had to borrow my wife's car to go to work. When I got home in the evening I was planning to spend more time figuring it out but when I I tried the key again and it started right up immediately, full electrical power like there was never a problem.

This is so frustrating because since this is so sporadic I'm afraid to go anywhere and get stranded, but if I take it to a shop the problem probably won't happen... Before this last episode when I actually paid attention to what electrical devices are working or not, I was thinking the issue was maybe with the ignition switch. But that shouldn't kill ALL electric power even in the off position, right? The battery is good, but I'm thinking for it to affect almost all electric it would have to be in the cable from the battery to the power distribution box... As far as I can tell the cable and connections are in good condition. And the thing that is really throwing me is that there was something working--that antitheft light on the dash. I appreciate any clues or areas to focus in on.

If you can "move the battery cables" then that's the problem, they should be tight, unmovable

Remove both cables from battery
Clean battery terminals with wire brush and do the same for the cable ends, scrape inside cable ends

You can get wire battery terminal cleaners like these for under $10: https://media-www.canadiantire.ca/pr...ab4e831929.png
Cleans the post and inside cable end


The reason the battery cable's wire size is so large is because they BOTH need to pass 70amps when starter motor is activated
If there is a poor connection on either positive OR negative battery cable then you get EXACTLY what you described, key on lights on turn key to START and NOTHING, the 70amp draw caused a disconnection on one of the terminals, and it heated up, once it cools down again it may work or may not

Thanks for the reply Ron. But when I had the most recent problem, I was getting zero power (other than the red anti theft light) no matter what position the key was in—off, no key at all… I couldn’t do anything to get the headlights or dome light to turn on. I might have forgot to clarify that. I do make sure the battery connections are cleaned off and I will clean them again, but if there was a battery connection problem why would the anti theft light be on but nothing else?

Because it draws maybe 0.02amps

Don't care about the outside of battery cables, they can have a "crust' on them, lol, only care about the inside, where the cable and terminal metal make contact

If key on doesn't get lights on the dash, and Headlights also don't work, and no dome light then battery is disconnected
Head lights and dome light have separate power than key on power
But all power comes from the battery when Engine is OFF