I have a 1986 Ford ranger 2.9 V6 I cranked it up to go to the store one night the headlights were surging but I just thought the battery might be weak so I drove it a mile or two down the road to the store when I got out of the store I turn the ignition key forward the seatbelt light and a emissions light lit up on the dash like normal I tried to crank it click the dash lights went out so I hooked my jump box up try to jump it off still nothing got it towed home went out the next morning to try to crank it after I charge the battery the seat belt light came on like normal I turned the key tried to crank it again the red light went out click everything in the cab is dead as a doornail and I haven't seen any lights since the door buzzer doesn't even buzz got a new battery still no lights I crossed the solenoid and it only spins any ideas?

 

Welcome to the froum

In 1986 there will be a starter relay on the inner fender by the battery, some call it starter solenoid
Battery positive cable runs to one of the larger Posts on this relay, and there will be several other wires on this one Post, this post is where ALL 12volt power comes from
Disconnect battery
Remove and clean ALL wires on this post
Several of the wires are Fusible Links, a fusible link is an "in line" fuse, just cheaper, lol
One of these wires runs to ignition switch, Yellow wire, but with an Orange Fusible link, color can change
That one wire powers everything when you turn key on

After all the wires are cleaned and reattached try key on again


There is no 12volts unless there is 0volts, the battery Negative connection
Electricity has to FLOW to energize anything, from a light bulb to a starter motor, so there must be a "circuit", a "circle", electricity can then FLOW from one "pole" to the other, energizing the device that's between the "poles", + and - in this case
So clean Negative cable(s) and both ends

And it could be your ignition switch has broken
Its under steering column above brake pedal, lots of wires
These older ones can split, usually can be repair with Zip tie
Unhook battery BEFORE working on an ignition switch, in any year


In the movies, or TV shows, when you see someone reaching under the dash on driver side and RIPPING OUT a hand full of wires, that's the ignition switch wires, and if you know what you are doing you can start the engine that way
Problem is...............they never have to deal with the LOCKED STEERING WHEEL, lol, which all vehicles have had since 1970's

 

That makes sense now that you said that it's probably the fusible link I believe you said the one that Powers the cab is the orange one correct ? I'm curious I believe I'm supposed to look for a break or burn in the wire correct? And from what I can see the wire runs from the solenoid across the radiator and grill and I believe over the driver side front wheel well correct? And it stays orange until it enters the calf correct? And then it ties to the yellow ignition wire switch correct? Also is that the only fusible link that could be affecting the power to my cab I honestly believe it's the fusible link although I have yet to found the brake in it I have been doing some research and from everything that I've looked up it sounds like the fusible length because my speedometer dances sometimes my temperature needle jumped up way past the danger mark one time and the engine wasn't running hot and from my experience it also doesn't sound like the ignition switch I don't believe because when I pull the headlight stop out the headlights won't come on and you don't have to have the ignition switch turned in the older model cars and trucks for the headlights to come on do you have any other information that might help me tracing down this problem in my fusible link? Thank you very much brother I really appreciate the information you have given me so far and any you could give me in the future also thanks again

 

No, a fusible link is 4" to 8" long

Looks like this: https://www.sherco-auto.com/mm5/grap...001/5/ET30.jpg

or this: https://cdn.shopify.com/s/files/1/04...g?v=1671058979

Fusible link will be on the SOURCE of the 12volts, so in this case on the Starter Relay post

Fusible link is used because its made with an insulation that won't "burn" when heated, and a wire that melts at a lower temp(like the wire in a fuse) so it will "blow" without starting a fire

Fuse or fusible links are always at the 12volt source, i.e. battery end of a wire
Battery-----fuse--------------------------------------------------------------------------------------------------------------------------device being powered

Fuse or fusible link is always rated 5amp under the wire size thats used

If a using an 18gauge wire then you would use a 15amp fuse or 20ga fusible link, otherwise the Wire becomes the fuse, lol

 

Got another question when I first bought the truck i took it to a mechanic but I don't think he quite knew what he was doing to be honest I took it in for a non electrical related when he got done and I went to pick it up he said that after he cranked it up when he was done and wire started smoking under the hood that was attached to the inertia switch and grounded to a screw underneath the gas pedal he told me that he clipped it off after that I was driving it one day I pulled up at Walmart went in Walmart came back out Cranked It up and right as I went to take off the windshield wipers came on by themselves and the truck started to to sputter tried to put my foot on the gas to give it a little gas and it sputtered out worse tried to shut the wipers off but they wouldn't shut off accidentally I flipped the high low beams and it stopped even though I thought it was weird drove fine and I went home didn't really give it much more thought till I remembered when I was at the mechanic shop I crunk it up and the wipers were doing the same thing that they were doing at Walmart they had never done that before the mechanic guy said that's weird looking at wire that he clipped I believe it's also a fusible link because it looks like one of the pictures that you sent me just curious if you had any thoughts on that?

 

It reads like you should get a mechanic that does vehicle electrics that can straighten things out

As none of that makes any sense at all
There is no ground for inertia switch, its a motion detection switch doesn't use power, just a pass thru

 

To be honest with you it didn't make any sense to me either I was basically retelling you what he told me I gave the guy 550 bucks way more than I wanted to spend I'm tapped out brother I went out there today and I moved the positive battery cable and I heard a click I'm curious in your opinion could it be a bad fuel pump relay? I stuck my test light in it and I only have one wire with power to it on the fuel pump relay I'm going to try to make a jumper and see if that fixes it if not I'll be back to testing wires

 

Fuel pump relay base should only have one 12volt slot with key OFF, then with key ON another slot will have 12volts

Ford used 2 types of 12v relays, mini and midro

Mini seen here: https://www.gtsparkplugs.com/images/...iring-840x.jpg

Micro seen here: https://www.gtsparkplugs.com/images/...lay-wiring.jpg

Slot numbering are the same function on both

85 and 86 are used to activate/close the relay, one is 12v the other Ground and relay closes, no polarity, either can be the 12v and the other the ground but it needs both

30 and 87 are the high amp contacts, these are connected together when relay closes
30 is usually the full time 12volts
And in this case 87 runs to fuel pump(via inertia switch)
But it can be wired either way for this system, i.e. 87 12v and 30 to fuel pump
If you jumper 30 to 87 fuel pump will have full time 12v even with key OFF



87A is used in some systems, like fog lights, you want high beams always OFF if fog lights are on, so 30 has 12v that goes to headlights when relay is OFF and when relay is activated fog lights get the 12v and headlights are off, no 12v