high school shop students need electrical help-Please

Vehicle: 1986 ranger 4x4, 2.9L, automatic.
Who we are: Small rural high school shop class in Nebraska
Cause: Student was given truck after dad passes away. Unfortuately sat outside under tree for 5 years.
Me: I'm the shop teacher that agreed to take on the project thinking it was simple tune-up. That and much more!
Problem: Something chewed just about every wire on passenger side.
Good News: we have 95% put back together.
Bad News: The wires were chewed so short to the EEC relay(brown) and we do not know which wires go where on the relay. There are 2 red, 1 yellow, and 1 black with green stripe. Yellow has power all the time. We get no power to any of the other 3 when switch is turned on. We also found an orange and orange/ brown set of wires loomed together laying on the passenger innder fender chewed and ends bare. Where might these go?
We also put new fuel tank, sending unit and pump in. In addition, we put plugs, cap and rotor. Also doing many more fixes, but we think this solenoid my be the thing stopping it from starting.
If someone could help and have a bit of patience that would be awesome. These kids dederve it, but I am at my wits end.
Thsnk you for reading.
Doug

Being a high school auto shop, don't you have access to vehicle wiring diagrams?

Checkout the How To Tech and other articles section here on the forum.

How To Tech: http://www.therangerstation.com/how-to/
Other Articles: http://www.therangerstation.com/articles/

should be some wiring diagrams in there that'll be able to get your wiring mess straightened out for you.

There are several very good Ranger gurus on this forum that hopefully will find your post and have some much better details as well.

Good luck with this project, hopefully you get it sorted out quickly and on the road. Sad that your student's father passed way, hope the student is taking the loss well.

BUMP++++ Come on TRS gurus help these kids out. Get them going in the right direction.

I'll send a couple PM's.

Wheres Ron D at? Lol

A lot of this is from memory so I am not be spot on. I can't find my 86/87/88 wiring book at the moment. Not sure why not, it's the size of the fricking Gutenburg Bible.


I believe your orange/brown wires go to the climate control system. Check the wires coming out of the blower motor and blower resistor for damage. Both are in the engine bay right in the area you described and are serviced by a small sub harness.

Now, IIRC the relay colors for that setup were as follows black was EEC, green was Fuel, and brown was the wide open throttle cutout for the air conditioning.

Here is a diagram that shows the relay wiring, but not the case colors:
http://www.therangerstation.com/tech_library/EDiagrams/files/Diagrams_ElectronciEngControls2_9_1of3.JPG

The big heavy yellow wire is the main key-off power feed. It brings power into many things including the engine bay relays and the ignition switch directly from the battery, so it should be hot all the time.

I will keep looking for my 2.9 wiring books, and maybe I will be able to shed more light on this once I have more complete diagrams. In the mean time I would suggest making this a learning experience on wiring diagnostics. Break out the ohm meter and teach the kids how to trace damaged wires to figure out what they are supposed to connect to.

Ok, found the book. I think you are looking at more than one part involved in this issue.

The WOT cutout is the only one of the three relays that has two red wires. None of them show a black/green wire. The WOT relay has the two reds, and two black/yellow.

The EEC relay is the only one that gets the yellow wire. Check the connection of the yellow wire at the black relay. If that power is not present at that relay the red wires will never get power, and neither will the fuel pumps.

Also, check for key-on power at the black relay from the red/green wire. I have no reason to think that is missing based on what you have posted so far, but it is another thing that could prevent the EEC relay from passing power down the line.

Check all that stuff and get back to us.

Thanks for the reponses thus far

As to my shop. I am a welding and small engine teacher. We are a very small school and do not have auto shop. I try to do my best with what ever the students bring in. I am trying to download pictures now.

rockets said:

As to my shop. I am a welding and small engine teacher. We are a very small school and do not have auto shop. I try to do my best with what ever the students bring in. I am trying to download pictures now.

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I applaud the fact that school still has shop. Most schools have cut it.

Same here. The closest high school to my house has a HUGE shop on site that's very well equipped. The whole program is shut down though, so it just sits there unused aside from a few adults that pay a semi annual fee for access after hours. No students touch it at all.

Pics of wiring

The pictures show the 2 red, yellow, and brown w/green stripe. We believe these go to relay. The pictures also show the orange and orange/brown wires that seem to come out together. There is actually another orange wire that has been chewed off that comes out of another loom.
I have been looking at schematics but am a bit lost.
Thank you all for your time and patience.
Doug

fastpakr said:

Same here. The closest high school to my house has a HUGE shop on site that's very well equipped. The whole program is shut down though, so it just sits there unused aside from a few adults that pay a semi annual fee for access after hours. No students touch it at all.

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Not to hijack, but how many kids nowadays would even wanna learn how to wrench? Like it or not the automobile hobby is dying, which is sad really. Shop class in general teaches you alot of skills that can be applied elsewhere in other occupations and even life in general.

rusty ol ranger said:

Not to hijack, but how many kids nowadays would even wanna learn how to wrench? Like it or not the automobile hobby is dying, which is sad really. Shop class in general teaches you alot of skills that can be applied elsewhere in other occupations and even life in general.

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I think you'd be surprised. At least around here, there's a growing acknowledgement of what's missed by not pushing the vocational side of education. My suspicion is that the trend will begin to reverse course over the next few years.

fastpakr said:

I think you'd be surprised. At least around here, there's a growing acknowledgement of what's missed by not pushing the vocational side of education. My suspicion is that the trend will begin to reverse course over the next few years.

Click to expand...

Unfourtantly, here that dont seem to be the case. Back when my oldest nephew graduated (06) i remember many late nights helping him and his buddies out in my barn wrench on everything from mid 90s Fseries to early 70s novas and everything inbetween.

Now my youngest nephew who just graduated in 2015, hell, half his buddies couldnt figure out how to switch a ratchet. My youngest nephew included, and none of them had any interest in anything that wasnt facebook.

I guess it could of been just different crowds, but the stark difference in just 9 years was shocking

rockets said:

The pictures show the 2 red, yellow, and brown w/green stripe. We believe these go to relay. The pictures also show the orange and orange/brown wires that seem to come out together. There is actually another orange wire that has been chewed off that comes out of another loom.
I have been looking at schematics but am a bit lost.
Thank you all for your time and patience.
Doug

Click to expand...

Ok Doug, your pictures show two important things, and missing one or two other important things.

Dead end your orange wires. They go to the blower motor that is shown to be missing. Cut them at the last place they aren't chewed and tape them off so you don't short anything to ground. They are not important to the issues at hand.

The EEC relay should be just forward of the pictured green relay. I can't see in the picture, but it almost looks as if it may also be missing. If you could, please let us know if that relay is in fact there or not.

rusty ol ranger said:

Unfourtantly, here that dont seem to be the case. Back when my oldest nephew graduated (06) i remember many late nights helping him and his buddies out in my barn wrench on everything from mid 90s Fseries to early 70s novas and everything inbetween.

Now my youngest nephew who just graduated in 2015, hell, half his buddies couldnt figure out how to switch a ratchet. My youngest nephew included, and none of them had any interest in anything that wasnt facebook.

I guess it could of been just different crowds, but the stark difference in just 9 years was shocking

Click to expand...

Some times it is just attitude. Sometimes it is just place in life.

When I graduated high school in 04 I couldn't figure out which one was the business end of a combination wrench. It wasn't until 06 when I got sick of the career I had been studying for since I was 8 years old that I made that change. I had quit college because I was sick of taking classes that didn't seem to be moving me in the direction I wanted to go, I had been working crappy minimum wage jobs and living in a crappy trailer changing my spark plugs every six months because it was all I could afford to do for "fun". My mom found a Ford program at a school two hours away and talked me into enrolling. Aside from super basic stuff like oil and spark plugs I had never worked on a car a day in my life when I started.