Explorer Swap into Painless harness

[staleb00]

Friends, need some help and guidance. I’ve been reading as many posts, videos, and looking at the painless guide over and over but may have gotten myself mixed up now, so looking to the community for some validation on my wiring work. Sharing a couple pics to help.

First area is the explorer harness. I created my own relay box from Amazon. 4 relays - PCM, Ignition, Fuel Pump, and O2/HTR. There’s a 15 amp fuse for the yellow KAM and OBD. Relays are fused at 20 amps. I added in a run wire using the NSS wire I took out which goes from the ignition switch and powers the diode, which then powers the 4 relays. Fuses are powered from B+ from starter solenoid and fuel pump is grounded from pcm. Everything I ground to bottom of starter solenoid. Just need a sanity check if this is right or I’m missing anything. Just don’t want to wreck my computer.

Staying in the engine bay. The alternator wire and ammeter wires are throwing me off. I think I can terminate the ammeter wire, fuse the yellow wire from the alternator to the open fuse slot in my explorer relay box. Is this right/possible? I’m trying to minimize the amount of wires that aren’t really needed. I’m also trying to minimize the amount of wires that are on the starter solenoid.

I also have the alternator running to 175a fuse, then to B side of the starter solenoid. Black/yellow on the B side of the starter solenoid as well. Do I need another midi fuse somewhere though? This is what’s confusing me, especially if I want to get rid of the ammeter wiring.

Next area is ignition switch. Pink wire runs to the start side of the ignition via a splice into the NSS wire that originally was there. My “Run” wire from the explorer harness (using the left over NSS) will get spliced into the black green wire that’s in the run terminal. Is this right?

 

[904Bronco]

If I understand your explanation... The ammeter in the cluster is no longer used, the 60amps unit wont live long with a 130 amp Alt.
I will add I haven't used a Bronco specific Painless harness in a long while, but if the harness has an Alt Batt feed wire, it won't be used with the Explorer G4 Alt.
It can be terminated in a safe manner, or it can be used for another purpose, such as power for a H4 headlight relay harness.
The Alt hook up is very simple following the diagram below.
The white/black stator wire is not used.

 

[staleb00]

Thanks! Painless has wire 915 that’s labeled “alternator b+ output” that’s supposed to receive constant 12v from the alternator. Then it has black 916 from the ammeter wire (972) that’s supposed to connect to the midi fuse on the alternator side. Feels like it just creates this random electrical loop. Is that right? Diagram below of what I have based on your drawing and things I’ve seen from EFI guys posts. But sounds like I can just take that 915 wire cap it for now and turn it into a headlight relay harness down the road? Appreciate the help. Electrical is not my favorite thing.

 

[Veez]

Thanks! Painless has wire 915 that’s labeled “alternator b+ output” that’s supposed to receive constant 12v from the alternator. Then it has black 916 from the ammeter wire (972) that’s supposed to connect to the midi fuse on the alternator side. Feels like it just creates this random electrical loop. Is that right? Diagram below of what I have based on your drawing and things I’ve seen from EFI guys posts. But sounds like I can just take that 915 wire cap it for now and turn it into a headlight relay harness down the road? Appreciate the help. Electrical is not my favorite thing.

Stable00 did you get a response on this yet? I'm working through the same issues right now

 

[staleb00]

I did. Reached out to Gary directly and he helped guide me through some of it. I connected 915 and 916 to the same side of my midi fuse which creates that loop I mentioned above. I’ll eventually take 915 and use it to power headlight relays.

For ignition wiring if that’s something you’re struggling with. Connect it with the oem coil+, red/green #920 that runs through the engine section. It’s fused which is safer than connecting directly to that black/green #933 at the run output of the ignition.

I also haven’t turned my rig on yet bc I have like 40 other projects I’m trying to figure out. So take the above with a grain of salt.

 

[Veez]

I did. Reached out to Gary directly and he helped guide me through some of it. I connected 915 and 916 to the same side of my midi fuse which creates that loop I mentioned above. I’ll eventually take 915 and use it to power headlight relays.

For ignition wiring if that’s something you’re struggling with. Connect it with the oem coil+, red/green #920 that runs through the engine section. It’s fused which is safer than connecting directly to that black/green #933 at the run output of the ignition.

I also haven’t turned my rig on yet bc I have like 40 other projects I’m trying to figure out. So take the above with a grain of salt.

I have another question stableb00. I picked up my engine and harness that was reworked by Gary for someone else. Gary sent me a print out of how/where to connect the internal wires and I believe I am good there. I've read and followed other post on connecting the POS+ battery cable Via mounted Solenoid to 175 amp fuse, 175 amp to 3g alternator. I'm going off your's and others post concerning the painless harness and how to connect into the solenoid as well. Where I am currently lost is the 3 wires from Gary's harness in the engine bay coming out of the fuse/relay box. One was labeled "Ground", so no issues there, the other two lost their labels at some point. They are both Red wires one being heavy gauge 8 or 6, and the other smaller gauge 14 or 12.. Any idea where to connect and what they are? I'm sure they are both power, I'm just not sure if they connect to the starter solenoid, if so to what post, or the mega fuse or somewhere else? The solenoid I'm using is the old OEM four post. Prior to the engine swap, I was running a carbureted 302 with the same 28 circuit Painless Harness. I understand the old voltage regulator will not be used and the only other wire I've connected from the painless harness is the 916 from the battery side of the starter solenoid to the mega fuse. Going off others post I have a 10 gauge wire going from the Solenoid Starter post to the small post on the starter. I also have a 4 gauge going from the POS+ Battery post on the Starter Solenoid to the big post on the starter. Any assistance would be appreciated!

 

[Veez]

I'm not sure how to post pictures for you?

 

[Oldtimer]

ADMIN - How to upload photos - Become a Contributor

There are two ways to upload photos to the forums; Free - Use an outside photo hosting site. Click here for instructions. $12 per year - Become a Contributor and help support the site. See instructions below. Become a Site Contributor! Click here to sign up. Contributor status includes...

classicbroncos.com

 

[904Bronco]

Where I am currently lost is the 3 wires from Gary's harness in the engine bay coming out of the fuse/relay box. One was labeled "Ground", so no issues there, the other two lost their labels at some point. They are both Red wires one being heavy gauge 8 or 6, and the other smaller gauge 14 or 12.. Any idea where to connect and what they are? I'm sure they are both power, I'm just not sure if they connect to the starter solenoid, if so to what post, or the mega fuse or somewhere else? The solenoid I'm using is the old OEM four post. Prior to the engine swap, I was running a carbureted 302 with the same 28 circuit Painless Harness. I understand the old voltage regulator will not be used and the only other wire I've connected from the painless harness is the 916 from the battery side of the starter solenoid to the mega fuse. Going off others post I have a 10 gauge wire going from the Solenoid Starter post to the small post on the starter. I also have a 4 gauge going from the POS+ Battery post on the Starter Solenoid to the big post on the starter. Any assistance would be appreciated!

Garry can and does wire things differently depending on what people are planning to do. But generally from his fuse box, you have the bundle of wires that goes inside, you have the ground wire, a main battery feed wire (large gauge red)(connect to + Batt post on the starter relay) and there is a small red wire that operates the starter relay. (Fords color was red/blue strip) Your prior painless harness setup maybe using it's own wire to close the starter relay, which would have to be modified to use Garry's setup. I am guessing/making an assumption at this point, having done a few Explorer conversions, but not being able to see what you have.
It sounds from your description that you have the PM started hooked up correctly. There is a wiring diagram in the PDF I attached for reference.

 

[Veez]

Garry can and does wire things differently depending on what people are planning to do. But generally from his fuse box, you have the bundle of wires that goes inside, you have the ground wire, a main battery feed wire (large gauge red)(connect to + Batt post on the starter relay) and there is a small red wire that operates the starter relay. (Fords color was red/blue strip) Your prior painless harness setup maybe using it's own wire to close the starter relay, which would have to be modified to use Garry's setup. I am guessing/making an assumption at this point, having done a few Explorer conversions, but not being able to see what you have.
It sounds from your description that you have the PM started hooked up correctly. There is a wiring diagram in the PDF I attached for reference.

Thank you!

 

[staleb00]

Alright. So finally got everything running but have a few problems.

First, gauge clusters go to max (fuel, oil, and temp). All 3 worked prior to updating to painless. Lights come on, blinkers work, hazards work. Doubled check the interior ground to make sure it has a solid connection and seems fine. Thoughts?

Second, brake lights. Not sure how I should connect this wire (green wire from explorer harness). Do I just splice this into the brake light wiring that runs to the tail light housing? Believe it’s a red/black wire, 918. Had it connected directly to the brake switch with the red/black 918 wire on the opposite terminal but didn’t work. If I connect the pre wired brake light wires from the painless, brake lights work fine. So feel like it’s missing power, but also thought the green brake wire from the explorer harness was hot.

 

[widowmaker77]

I’m trying to remember how mine is done but the green wire you’re talking about, isn’t it for the ecm to unlock the torque convertor on the 4r70w? If so mine is wired to one side of the bake switch on the pedal.

 

[staleb00]

That’s my understanding as well and what I did, but am getting no brake lights. I also replaced my steering column to an ididit tilt. Everything works at the column, including hazards. In case that helps anyone diagnose.

 

[Bruners4]

The ECU brake wire is connected to the same wire as the brake lights wire on the brake light switch. It is in addition to the brake lights wire and is only a signal to the ECU that the brakes are applied. The wiring harness connection is required for the brake lights to be powered when the brakes are being applied.
If you are also installing the Explorer cruise control, it also is connected to this same terminal of the brake light switch. It also is a signal that the brakes are applied and cancels cruise control.

 

[staleb00]

Thanks! I’ll splice it into the brake light wire running to the brake lights.

Now anyone have thoughts on the gauges?

 

[Oldtimer]

My understanding is;
If IVR* does not have a good ground it will output a full 12v and peg the meters.

* IVR, instrument voltage regulator, pesky little unit on back of speedometer cluster, where you can't see it or get to it.

 

[fordguy]

Brake switch disengages t/converter when brakes applied via signal from computer. That is why it is in the loop.

 

[staleb00]

Yea. Think it may be a bad IVR. Ordered a new one so I’ll update once I install.