Edit: Just want to make sure i mentioned that fuse 7 does have power to it 12V, and the fuse has good continuity as well... Fixed my multimeter so i got that back up again for testing purposes.

well I double checked the 30 a fuse you mentioned and it was good. Just came back with a new relay and plugged it in and no change. They also don’t sell the diode either. Not sure now what to do

 

Also ron for testing purposes can I bypass the relay and give the pcm 12 volts? Like make a space jumper and jump the relay connections to see if the computer powers up? I don’t have a copy of the wiring starter circuit. I got the fuse panel diagrams.
id just like to see a sign of life back in the truck. My guess is that bad blizzard either shorted or damaged a wire.

a friend suppose to come by tomorrow to try and help me go through all the wires. I suppose one good thing is I’m learning a lot with the problem.
ive always poked at projects

 

Yes you can use a short jumper in the PCM relay socket

4 slots should look like this: https://www.dsmtuners.com/attachment...am-jpg.337897/

85 and 86 are the COIL hook ups, it closes the relay when it has 12v and a ground
With key on you can check both, see if either has 12volts from diode
(I get those diodes and handfuls of fuses and relays from wrecking yards)

Slots 30 and 87 are the LOAD slots, these are where the jumper would go

There are also 5 pin relays /slots, seen here: https://ls1tech.com/forums/attachmen...wire-relay.jpg

87A is added, it won't be used on the PCM relay setup, its there for Double LOADS, you would have fused 12volts at slot 30, when relay is OFF this 12v would go to 87A, when relay is ON 12v goes to 87 and 87A is OFF no power
Just FYI

 

ok I’ll try jumping the relay tomorrow. Also was looking up how to test a diode, never realized the multimeter has a diode function built into it. I’ll test the diode tomorrow for it’s function.
hopefully the problem will be sorted out soon.
it is a 5 pin relay, I never realized how relatable the coils are. I learned some stuff like this in school in industrial applications, trying to apply it here as well!

thanks

 

87A is not used, the 5 pin are just more common and pretty much the same cost

If you test for 12v at 85 or 86 with key on that would also test the diode, if say 86 is 12v key on, then test that 85 is a good ground, or visa versa, could be PCM relay lost its ground

A diode only allows voltage to travel one-way >>>>>>>diode>>>>>>>
In this case it lets the 12v from fuse 19 travel to the PCM relay coil, in this relay there can be a "kick back/flyback" voltage spike when it close, diode keeps it at the relay

 

Update:
was just out testing. Based on the diagram you attached, i tested 86 ( Ground ) using my test light. It has good ground. I then tested 85 to Ground using my test light, it does have good KeyOn power. I then tested 87 to ground with the test light for Direct 15 Amp power and i do not have power to 87! The test light won't light up.
As you mentioned I would have to jumper 87 to 30, however without 87 having battery power I need to find that circuit.

Also based on testing the diode with the diode function it does behave as it should and only allow current through one way and shows OL in the other direction

 

Relay slot 30 can have the fuse 7, 30amp 12v, diagrams are not always correct, 30 and 87 are interchangeable as far as wiring up a relay

Diode is good if you have 12v on 85 or 86, key on
If relay doesn't "click" when you plug it in, key on, then relay is bad

 

Update:
i got the truck running! I gave 12 volts power to the 87 slot since it doesn’t have power. I think the main 12 volt fused 87 wire was broken. If I provide 12 volts directly to the slot for the relay the truck fires up perfectly.
So I think there’s a wire broken that’s +12 v fused from battery for the pcm.

 

Glad you got it running

BUT..............test slot 30 for 12v

87 or 30 can be the 12v power
So 87 or 30 can also be the LOAD slot
So applying 12v directly to slot 87, if its the LOAD side, would get the PCM power, but not solve the problem

 

yes for sure! super happy to hear it run. I got it temporarily running which is perfect cause now i can move it over to the garage and try to figure it out. You mentioned that 87 or 30 can be the power source. What would be the best route to fix this? The temperature here is very cold so the wires are pretty brittle or stiff. Do i remove the fuse box? Everything else seems to be working good except for not having power to 87 terminal when testing. So I assume that 87 gets its power from somewhere. On the diagram you provided it just says 15 A to Battery, however i have no wiring diagram to try and trace things out. When i google wiring diagrams, im mainly finding Radio diagrams and such. The switched power works, the connection to PCM is good, The ground for the relay is good but the +12V for it is not there.

Thank you highly, means a lot to get the truck running at least. Now i have something to work with!

https://ls1tech.com/forums/attachmen...wire-relay.jpg

 

The diagram was for slot placement so you could see where 85 and 86 were in relation to 30 and 87, its NOT a Ford PCM relay diagram

In my Ford diagram slot 30 is the 12v from fuse 7, and 87 is OUT to Load(PCM)

So test for 12v in slot 30, full time 12v, you can pull fuse 7 to confirm 30 is 12v from battery

If it has 12v then 30 and 87 wires are OK, no need to pull the fuse box, because you already know applying power to 87 powers up PCM, so that wire is OK

So relay is the problem, its not connecting 30 and 87 when Coil is powered on

 

oh okay, I didn’t know ford used their own relay, I thought it was a standard or universal relay. When I went to the parts store they sold me another relay with same pins and told me it was the same because it’s a standard relay. It didn’t work with the aftermarket relay I bought.
i was following what was in the diagram when I was testing.
ill test the above and report back

 

Yes the relay is universal as are slot lay outs, the WIRING is up to each company or person

30 and 87 are interchangeable, as are 85 and 86, neither has "polarity" issue

There are also micro/mini relays used now, with slots like this: http://www.proquip.com.au/assets/ima...ys/relay-g.gif

1 and 2 are the same as 85 and 86, and 3 and 5 are the same as 30 and 87

4 would be 87A

 

Hi Ron, I took a few pictures of what I am seeing, hopefully you can help me indentify a fix. At least we identified the main problem with the truck. I got the truck PCM on a toggle switch for the time being so its not fully disabled. I know kinda of funny, and dumb however I can move it around until I get this fixed properly. The truck is my daily driver still so I need it fixed properly.
I tested Fuse 7 as you mentioned. The fuse is good and shows good continuity. I also get voltage to one side of the terminal when i remove the fuse with the key on like you mentioned. I took a couple videos show i can try and show you what i see as well. I still think theres a wire broken somewhere, however you have a better understanding then me.
I don't have power still to pin 87. So i think thats the issue.


Fuse 7 Power Link:
Test Video 1:
Test Video 2:
Test Video 3:
Temporary toggle switch power to PCM:

P.s going to owe you a tims card after this one ! haha

 

I didn't see you test slot 30?

It should have 12volts all the time, for sure, and from fuse 7, so that's your missing link

With key on did you plug in the relay and did it "click", if so then 85 and 86 are OK

87 is the "power OUT" to PCM, and other devices, which is why the toggle switch works

30 is the power IN from fuse 7, which, assuming relay "clicks", does not have 12volts

According to the diagrams there should be a Yellow/Black stripe wire from fuse 7 to slot 30 under the fuse box

 

slot 30 has no power. Just went out and checked it again. Also if I plug in either the old or new relay I get no click. Ok I’ll try taking up the fuse box tomorrow and see if I can locate the yellow black wire.

 

No voltage on 30 is the problem, well 1 problem, most likely the yellow wire is corroded at Relay end but can be fuse end as well

But the relay should "click" if key is on when you plug it in

So 86 is a good Ground?
And 85 has 0 volts key off and 12volts key on?

These can be wired either way, as said the diagram you are using is just for layout, not wiring
On my 2003 diagram 86 would have 12v key on and 85 is the full time Ground

On the next year its reversed, so it can be either way

 

yes you can see in my little YouTube videos, I have a good ground and good switch on power. I don’t get a relay click at all. If I plug the relay in and turn the key on I get no change. I never checked key On power with the key in the off position. Yes I’m just following your diagram for the idea,it has helped drastically. I think a wire is broke or corroded for sure. We have salted roads and the truck is now 17 years old. I will try the ford relay from the blower tomorrow and throw in the slot to hear if it makes a click.

 

Try a 9v battery or the truck battery on the relays, pins 85 and 86, polarity doesn't matter, and they should "click" when they have + and -

And thats what should happen if slots 85 and 86 are working with key on

 

checked both the old relay and the new relay. They both work when I apply a battery to the terminals directly.
So that leaves me confused because when I checked with my test light, I do have a good ground and a good 12v to it. Unless the receptacle where the terminal slots into it corroded cause that doesn’t make sense to not hear a click. So there’s that problem and the no power to 30 slot.

so I think I need to take the fuse box up and possibly replace the fuse box or wire up an external relay most likely.
Is there a source for getting the full wiring diagrams? I never noticed it in the manual. I know yellow with black wire is the main culprit. I watched a YouTube video of a 02 ranger 3.0 which had the exact same wire corrode off

 

I would think both the 12v wires at that relay base are corroded then

A corroded wire can show 12v but no amps, so when a load, like the relay's coil, is applied, the volts drop below 5v so can't activate relay

This is the pin number diagram I have

 

And yes you can certainly use an added relay and base, just needs key on power to activate relay and then a 30amp inline fuse
But fixing the existing base would be better long term

 

I’ll poke at it soon and see what I’m up against. Do the slots pop out? Like is there a way to fix the base? I tried to start the truck earlier but I turned they key, it went into theft mode. I killed the toggle switch again and tried again and it was fine haha.
once this is sorted out I got to figure out my power windows. Both died on my over the last two weeks. I got two new motor assemblies ordered. The driver side one was very slow.
also on a side question, if I swap out my driverside door for a non power lock door would that affect anything in terms of pats or anti theft? I’m gonna be painting the truck this spring and cleaning it up. I got a perfect shape driverdoor in my garage. I never swapped it yet like the passenger one

 

Fuse 12, 20amp, in engine fuse box powers the windows, so maybe there is more corrosion going on than just the PCM Relay wires

Yes, all connections in plastic holders are "pinned", so the slot connections will all come out, usually you need a small, very small, screwdriver that you insert into the back or front side of the connector to push in small "arms" that hold metal connector to plastic "shoulder" so it doesn't slide out on its own