4.0 Swap into 1986 Ranger - Electrical Help Needed

[TrapperMan2024]

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

I have a manual trans, can I remove the gear position indicator cable?

 

[TrapperMan2024]

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

The guy I bought the harness from, didn't mention anything about the harness being from different vehicles... I'll check my chilton manual and see if the colors don't match up...

 

[RobbieD]

I have a manual trans, can I remove the gear position indicator cable?

Yes.

On manual trucks, a blank plate replaces the gear display. The entire display can be removed with two 7mm screws (one shows in your pic).
Same dash in a '90 model:

You can either leave the display to fill the hole, or get a blank plate from a manual cluster and then swap them out.

Or even, tear the needle and cable out and paint the display black to blank it out.

Can't remember offhand if the clear lens has to come off (but it's easy) of the cluster or not, in order to pull the display.

 

[RobbieD]

The guy I bought the harness from, didn't mention anything about the harness being from different vehicles... I'll check my chilton manual and see if the colors don't match up...

It's better, if possible, to look at these two wires with the bulkhead connectors loose, but mated, to check how they pass-through.

Don't take me wrong here, but when looking at connectors it's easy to forget that that you have to remember that they're "mirror images" when you look at one, and then the other. Mated connectors make it much easier to see the wires in how they pass through on both sides- especially a big connector.

I would be looking at this:
Do the 2 Yellow wires have +12 volts at the bulkhead connector?
And if "yes", is there also +12 volts at the ignition switch? The ignition switch power wires should be Yellow wires, too, but anything is possible.

You're getting there. Good job on getting an EVTM.

 

[TrapperMan2024]

It's better, if possible, to look at these two wires with the bulkhead connectors loose, but mated, to check how they pass-through.

Don't take me wrong here, but when looking at connectors it's easy to forget that that you have to remember that they're "mirror images" when you look at one, and then the other. Mated connectors make it much easier to see the wires in how they pass through on both sides- especially a big connector.

I would be looking at this:
Do the 2 Yellow wires have +12 volts at the bulkhead connector?
And if "yes", is there also +12 volts at the ignition switch? The ignition switch power wires should be Yellow wires, too, but anything is possible.

You're getting there. Good job on getting an EVTM.

Thanks RobbieD, I am frustrated at the possibility that the previous owner might have swapped wiring harnesses, but I guess it'll only teach me more about vehicle wiring...

 

[RobbieD]

Thanks RobbieD, I am frustrated at the possibility that the previous owner might have swapped wiring harnesses, but I guess it'll only teach me more about vehicle wiring...

I understand the frustration. And swaps present their own special challenges.

Seriously, I think that you're best bet is to "go back to the basics" on it, by using the EVTM diagrams as a guide, and checking voltage (and ground) as needed and where needed. Start at the source (the battery) and methodically work your way through a problem circuit until you find, and correct the problem's cause.

That's where I was leading to, when I asked if you were getting 12 volts on the yellow wires before/after the firewall.

The wiring diagrams will tell you how the electrical system worked originally in an Explorer, and it can be made to do the same thing in a Ranger.

If it's any consolation, only insane persons actually like working on electrical . . .

 

[Curious Hound]

If it's any consolation, only insane persons actually like working on electrical . . .

I'm not sure whether I've just been put down or praised. Are you qualified to diagnose me that way?

 

[RobbieD]

I'm not sure whether I've just been put down or praised. Are you qualified to diagnose me that way?

Praised, my friend. And my diagnosis is based upon the insane fondness that I have for my own former profession.

"Old electricians don't actually retire; they just burn out."

 

[TrapperMan2024]

I understand the frustration. And swaps present their own special challenges.

Seriously, I think that you're best bet is to "go back to the basics" on it, by using the EVTM diagrams as a guide, and checking voltage (and ground) as needed and where needed. Start at the source (the battery) and methodically work your way through a problem circuit until you find, and correct the problem's cause.

That's where I was leading to, when I asked if you were getting 12 volts on the yellow wires before/after the firewall.

The wiring diagrams will tell you how the electrical system worked originally in an Explorer, and it can be made to do the same thing in a Ranger.

If it's any consolation, only insane persons actually like working on electrical . . .

So, tonight I had some progress, found the cable going from the starter solenoid to the starter was showing a lot of ohms so I started feeling it and it was really hard near the exhaust, so I opened it up and found a bunch of corrosion in and around the wires, so I replaced the whole cable with a 'new used one'. I also found the cable connection at the battery to have a similar corrosion problem and while I was wiggling on it, it came out of the lead terminal. So I cleaned that up and put some terminal oxidation gel stuff on it and put it back on the battery. When I went over in the cab and turned the key one click to ON, and the fuel pump engaged!

So one problem solved, and now many more to start looking into...

 

[TrapperMan2024]

I'm waiting on a 'Triple Function Clutch Switch' to add to the pushrod on the clutch pedal... In the meantime, I thought I would start mating the 94 wiring harness to the pigtails I left for the stock lights... While I was doing this I found two 'plugs' under the dash. See pic:

You can see that its the main harness coming through the firewall, then the harness splits and goes to the dash, and it also goes to the black and gray plug. I've looked in my Chilton wiring manual (still waiting for ebay to ship me the EVTM manual), and I can't figure out what they both go to. My best guess is that MAYBE one of them is there to go to a 'Park/Neutral Position Switch'? But the wiring schematic only has 2 wires for that.

The previous owner gave me an old cut up harness as well, so I have these two plugs as well:

The last two pictures are similar to what's under the dash (both female plugs). Are there supposed to be plugs that go to them, something like a bypass plug? Thoughts?

 

[SenorNoob]

IDK about the 1st picture, but the second 2 are for a radio...

 

[TrapperMan2024]

RobbieD, I just recieved the EVTM manual in the mail today! WOW! Its amazing, to think that the last 30 years I went without knowing about this amazing resource...

So tonight, using the EVTM, I found out that the 1994 Explorer Wiring is incomplete... the previous owner did not include the Electronic Shift Control Module.... so, I wont be able to use 'push button' 4-wheel drive. The transfer case is a 1354, anyone know where can I find a 1354 manual shift? Or can I swap in the original 86' 1350?

 

[SenorNoob]

The 1350 will absolutely work. As long as the front driveshaft is the right length. Easy enough to check. Install it and see how much spline engagement you have at the transfer case.

 

[TrapperMan2024]

More electrical help needed...

Yesterday I received my new clutch line and installed it with no issue. I put a new triple function switch in (that requires the driver to push in the pedal to start the vehicle). I hooked up the battery and turned the key... fuel pump turned on and pressurized the system. I turned the key to START, and I heard a 'click', the starter didn't engage, so I figured I must have a bad solenoid. I grabbed some wires with alligator clips and confirmed that the starter solenoid is working. I then ran a wire straight from the battery to the small terminal on the solenoid (3 post style), and the starter engaged and turned over the motor! success!

Why didn't the ignition key turn on the starter?

I had to run kids around, so I disconnected the battery and put it back on the trickle charger for a few hours... I returned and when I went to turn the ignition key again, fuel pump engaged and then I turned it further to engaged the starter, and I heard the click again and then this time, everything shut off, like a major fuse blew... so I check all fuses. Nothing.

Waited 30 minutes with the battery disconnected, and again it did the same thing. What is going on????

 

[RobbieD]

I heard the click again and then this time, everything shut off, like a major fuse blew... so I check all fuses. Nothing.

There's a good chance that you have a bad main battery cable, and it can be either the positive or the negative cable.

Check both cables carefully, for green rot on the inside, at any point but especially close to the battery post terminals. If I'm not mistaken you've transplanted in a later Explorer power distribution box; be sure to check it's power supply connection, too.

Flex the main cables, and listen and feel for a "crunchiness". Cables can look perfect, but be completely rotten on the inside.

Your description is classic for a bad main cable; it can pass a certain amount of electrical current, but when high current flow occurs (the starter) the bad spot heats up and conductivity shuts down.