4.0 Swap into 1986 Ranger - Electrical Help Needed

[TrapperMan2024]

Hey All-

I have great success with swapping my engine, but the last few days I ran into some issues...

When I pulled parts from my donor 94 explorer, I took the 100% entire wiring harness, (it was running when I pulled it). I labeled it well and have plugged everything back in and matched all my labeled plugs (so I'm confident that's not the issue)... but electrical stuff isn't my strong point...

I dropped a battery in, made the connections, and nothing lights up in the dash, and I don't hear the new fuel pump turn on (it does test out). All I can get to work is the starter to engage. What have I missed? What wires should I trace?

 

[Uncle Gump]

Fusible links at the starter relay.

You have them on the battery side of the relay? They should be hot at all times.

 

[RobbieD]

I'm having trouble with the starter engaging, but nothing else part.

There are the fusible links that were with the original '86 electrical, but if you swapped in '94 Explorer harness "complete", it should have the underhood power distribution box, which would need to be supplied with power from the battery.

Some pics of what you've got may help us more in helping you with figuring it out.

 

[SenorNoob]

So did you swap dash too?

 

[RobbieD]

So did you swap dash too?

My understanding is that he did swap in a later dash, according to an earlier thread:
https://www.therangerstation.com/fo...-steering-and-dash.210536/page-2#post-2081324

 

[SenorNoob]

Ok. So all factory wires. I'd double check fuses...

 

[TrapperMan2024]

I'll get pics on Monday night, but to answer some of the questions above... everything is 1994 explorer. Its basically an explorer with an 86 ranger body. I checked fusible links last night and they were hot and supplying 12V to the starter solenoid, which is why i was able to turn over the motor. Any other ideas? Anyone know which wire supplies the dash with 12V?

 

[RobbieD]

These are '94 Ranger schematics, but it should give you something to start with.

I checked fusible links last night and they were hot and supplying 12V to the starter solenoid, which is why i was able to turn over the motor.

Did you run a main power wire to the new power distribution box which is on the Explorer harness? See the red arrow I put in on the first page.

On the first page you'll see Yellow coming out of the power distribution and going to (powering) the ignition switch. On this second page shows Brown and Yellow/Lt Blue feeding the interior fuse box. Use a meter or test light to see where power is, or isn't, using the diagram as a guide.

 

[TrapperMan2024]

I will check tomorrow night, but should I have to run a new wire, when I'm using the original harness? (electrical stuff isnt my strong suit).

Also, where did youget a book like that, its way better than my chilton...

 

[RobbieD]

I will check tomorrow night, but should I have to run a new wire, when I'm using the original harness? (electrical stuff isnt my strong suit).

It depends, on what all you used and where/how some of the connections were made.

For example, you didn't swap in the Explorer battery, right? Even though the motor, dash and a wiring harness are '94, they still have to electrically "touch" the '86 truck for some things, like power and lighting.

Pictures of certain things would help us see things, but you'll need to be able to do some basic troubleshooting and testing on your end.

[/QUOTE]
Also, where did youget a book like that, its way better than my chilton...
[/QUOTE]

I got mine off eBay. That's the Ford factory wiring manual, called an EVTM.

 

[SenorNoob]

That's an EVTM. Electrical Vacuum Troubleshooting Manual. It was for dealers. They show up on Ebay regularly from closed dealerships. They are year specific.

Here is one for a 94 Explorer. Cheap enough I would buy one if my wiring wasn't already a total mess of my own making.

 

[TrapperMan2024]

I ordered the EVTM manual (thank you for that recommendation, RobbieD & SenorNoob). I traced two 10ga yellow wires all the to the junction block that goes through the firewall. And they are both 'numbered' 47 & 50... see pic:

...but the wires are green (10ga) on the inside of the cab that correspond with the 2 wires. Could this be my issue?

 

[TrapperMan2024]

While I was pulling the dash apart, I also noticed this little thing:

... its a little 1/8" diameter white plastic tube, that has a black plastic knurled knob. When I spin it nothing happens or changes. What is it?

 

[RobbieD]

While I was pulling the dash apart, I also noticed this little thing:
View attachment 127633
View attachment 127635
... its a little 1/8" diameter white plastic tube, that has a black plastic knurled knob. When I spin it nothing happens or changes. What is it?

That's the gear position indicator cable, for the auto trans display in the cluster. It's supposed to go to the column shifter.

 

[RobbieD]

I ordered the EVTM manual (thank you for that recommendation, RobbieD & SenorNoob). I traced two 10ga yellow wires all the to the junction block that goes through the firewall. And they are both 'numbered' 47 & 50... see pic:
View attachment 127628
...but the wires are green (10ga) on the inside of the cab that correspond with the 2 wires. Could this be my issue?

What's the story on the harnesses? Did both engine bay side and cab side come from the same donor truck?