Ive been chasing down this problem for a few months now. I have a 92 f150. 4.9l, mechman alternator, ford taurus fan w/ dcc fan controller. What happens? When I go to start my truck everything works and I have power to everything, go to start, I get an initial click for the starter engaging, then nothing. Try to start again and no power at all. In March, the battery was replaced as well as the starter solenoid. That lasted for a little while then it got to a point where I had to put my battery on the charger every night. I replaced the starter last month thinking it was the problem since it was the original stater that came on the truck, no luck. Replaced the ignition switch, since it was falling anyway, still no luck. I had led headlights and switched back to halogens, still no luck. Recently I disconnected my light bar thinking there was some short there and things were fine for about two weeks then I go to leave for work, get in, key on, everything powers up, go to start and get a click then no power. Prior to this time I took a two hour trip , make a stop at a gas station things are fine, drive not even two miles down the road and start to back in a parking spot and truck cuts off no power at all I wait about 10 mins try one last time truck starts like nothing even happened. I have a digital volt meter in the truck and while driving around my voltage is fine. This problem only happens when i got to start my truck and what ever is causing it also is draining my battery too but its an all of sudden battery drain because I have checked for an amp draw several times. The only thing I can say that is common between the road trip and this time is the rain. Im going insane trying to figure out what could cause this problem.

 

Well, it sounds like you have two separate problems, at least from my experience with the first one you list.
If you lose all power to everything after the click, that's usually a battery cable. It was for me, and has been for many other people over the years. Yours may look fine, but have failed internally.

The factory ones last a surprisingly long time, but they are still just battery cables. The one and only that failed on me was an aftermarket cable that was less than three years old. Looked brand new, but would fail intermittently.
This will NOT drain the battery, but it can cause a condition where it's not always charging fully and the battery gets lower as you drive. But I'm thinking your dead battery is another issue.

If you don't drive your truck every day (or even if you do) when you park it at night disconnect the negative battery cable and check the voltage before putting it up for the night.
then check the voltage again in the morning and see if it starts after you re-connect the cable. If the reading was substantially lower in the morning, or if it would not start, then it's the actual battery that is failing. If it's still good, then you will have to start tracing backwards and do all the usual tests for parasitic drains.

Good luck.

Paul

 

I would agree with cables. Check each end of the cable by taking them loose and thoroughly cleaning them and the surface they mate to. If that doesn't work, then replace the cables. Check you battery voltage as described above,replace as needed If that still doesnt solve it then start narrowing down parasitic draws.

A friend of mine had a similar issue with a parasitic draw and come to find out it was the stereo someone had installed and wired improperly. He found it after I told him to start pulling fuses, one at a time and letting it sit over the weekend (it never caused an issue if he drove it every day, only when it sat for a couple days) until he found the circuit that was causing the draw. Once it was found to be the stereo , he then resolved the issue.

 

If I might add one thing. When you disconnect the battery wait 30 minutes before testing the voltage. It gives the battery time to disperse the "surface" voltage and you will get a more accurate reading so when you test it again in the morning your test will be more accurate.

 

I'm inclined to lean toward the battery cables. NO aftermarket ones, go to a trucking or ag outfit that builds custom cables and have them matched. You'll get proper gauge sizes, copper wire, and a solid connector. Well worth
the $

 

I checked for a parasitic draw today and came up with nothing, also if battery cables were failing or connection is bad I should be able to see that on digital volt meter since it would effect my voltage even when the truck is on right?

 

Maybe. If they are failing internally or are corroded at the connection or internally it may or may not show up until you hit a bump,jar the truck,etc... the best way to eliminate them as an issue is to replace them and clean all connection points. Next to the battery on passenger side inner fender is a stud that a ground wire goes to. pull the nut off it, clean it and all connections to it it and reattach it, see if that helps, it's common for that one stud to become corroded and can cause issues.

 

I agree with the others, it's a cable problem. BUT the VAST MAJORITY of the time it is a dirty or loose cable CONNECTION. You replaced the battery, but you need to remove the cables from the posts and clean them and make sure they tighten up properly. Make sure all the cables that hook onto the fender mounted solenoid along with the positive battery cable are clean and tight. Unhook the other end of the cable that hooks onto the negative battery and clean it and make sure it is tight.

If that doesn't solve the problem, then start replacing cables.

The phenonium you are experiencing is hard to imagine happening this way until you have experienced it and solved it.

 

Yep, what they said. You usually can't see it with a meter because even a small gauge original and semi-ancient cable is capable of flowing enough to register 14-15 volts on a meter at low loads, and more than enough to pass a resistance test. Even a single strand of 6ga cable will show zero ohms resistance, but still not be able to handle it when the starter tries to utilize it.
Once that much load is placed on a compromised cable, it's all over until you can get it to re-connect internally. Eventually it just won't...
I don't think even a voltage drop test would show it, because it's almost like a light switch when this happens. So there is no measurable loss when it goes instantly to zero.

It's possible that for the same reasoning your Black w/yellow power feed to the cabin has a fusible link that is blown, but still has enough conductivity to make the connection some of the time. But when those occur, it's usually enough to start the vehicle but you see the loss in other ways once up and running with other accessories turned on.
It might flow enough to let the key energize the starter relay, but once you try to run headlights, hazard flashers, heater blow motors and such, you start to see problems. If all of your other stuff works fine when the engine is running, then your fusible link is probably fine and we're back to the main cables.

Too many people have experienced this for it to be a fluke. I just happened to have it happen thirty years ago, but it's still happening to others so cable deterioration is still a valid concern.
It's one of the few times where most of us will recommend just throwing parts at a problem. It's a shame, but it's just too hard to test in most cases. And cables are an inexpensive upgrade if you use this opportunity to up-size to 2ga or so.
The only real issue I see with trucks of this vintage, vs the older stuff, is that the battery cables are integrated into the harness, run hither and yon over hill and over dale, so are not just a five minute proposition. You can even buy new, factory replacements with all the associated wiring loomed together.
The issue for some of us is that you end up paying $40-$200 for the same thing you could get for $10 if you just replace a cable. So we're not taking this lightly. Just that sometimes cables are better off replaced.
Sometimes you just need to cut the old ones out of the loop, leave all the other wires in place, and simply bypass your old ones with a brand new larger gauge version. It can be done cleanly, but I guess we have to look at your particular truck to see how easy/hard this might be. My '93 is not super bad, but it sure isn't my '71!!!!

Good luck.

Paul