E4OD For Dad’s Truck

[Gary Lewis]

I'm pretty sure the relative position of the various components will change greatly. No reason the PDC box could not be mounted to the right fender, or dispensed with entirely should you choose some other method of power distribution. Your 90 huck likely has a small bank of relays on the L inner fender. These are the PCM power relay and fuel pump relay. For the purposes of EFI, this is all you need, but there are a lot of circuits you can address with that PDC from the 96 truck.

What I am planning to do with my truck is to build my own PDC. I want to incorporate relays for headlights, HVAC fan, ECM power and fuel pump. I like the idea of mega fuses as opposed to fusible links and would incorporate this as well.

That starter relay has been a common feature of Ford vehicles, but the 96 used a PMG starter and those had a solenoid/bendix throwout much like a GM starter. Result is you have the fender relay controlling the coil on the starter mounted solenoid as opposed to the older starters where the entire starter current passed through the fender mounted relay.

And yes, the snow may be here to stay.

Ray - I’d like to minimize the wire splicing, so if the ‘96 PDC fits on the left fender and has all the relays and fuses I need, then that would be perfect. Obviously the Bullnose fusebox is just on the other side of the firewall, so if we tease the original fusible links out of the Bullnose harness we should be able to power them from fuses in the 96 PDC.

But aren’t the relays for the PCM power, fuel pump, etc in the 96 PDC? Hmmmm, gotta go look at the diagrams you sent......

[NotEnoughTrucks]

Ray - I’d like to minimize the wire splicing, so if the ‘96 PDC fits on the left fender and has all the relays and fuses I need, then that would be perfect. Obviously the Bullnose fusebox is just on the other side of the firewall, so if we tease the original fusible links out of the Bullnose harness we should be able to power them from fuses in the 96 PDC.

But aren’t the relays for the PCM power, fuel pump, etc in the 96 PDC? Hmmmm, gotta go look at the diagrams you sent......

Yes they are. My thought were more towards accommodating lights, HVAC, etc.

It becomes a lot more clear when you have the wiring in hand.

I'll send you my entire manual file. Still working on indexing and relabeling, but there is a lot of info there.

[85lebaront2]

Bill - Thanks for the clarification. On the easy bit, if I’m driving the headlights with the truck’s original headlight switch plus some relays then there’s no worry about the DRL, with or without bypassing.

On the PDC, that ‘96 version should work out well. I may even be able to move the power feeds to the cab to it, using real fuses and eliminate the fusible links. Hmmm, if that harness has the headlight wires like the 90’s harness does then they’ll be fed by relays in the PDC and all I have to do is to trigger them with the headlight switch and dimmer switch. 👍

As for the solenoid, I don’t know what the flat one looks like, but I think one of those and a megafuse should work nicely. That solenoid is surely set up to handle a PMGR starter.

Gary, no headlight relays were used on the older trucks, the newer switch may be more capable of handling the current draw of the bulbs, or the newer headlights don't draw as much current as the older ones.

On another note, your ICVR (I think that was it) thread on FTE, do you still have the information on building one? I am thinking of doing one for the Chevstang I am working on for my parts source, Donnie Medlin.

[Gary Lewis]

Gary, no headlight relays were used on the older trucks, the newer switch may be more capable of handling the current draw of the bulbs, or the newer headlights don't draw as much current as the older ones.

On another note, your ICVR (I think that was it) thread on FTE, do you still have the information on building one? I am thinking of doing one for the Chevstang I am working on for my parts source, Donnie Medlin.

Bill - So the ‘96 doesn’t have headlight relays? Ok, maybe there are relay spots in the PDC I can use.

As for the ICVR, just go to Electrical/ICVR.

[85lebaront2]

Bill - So the ‘96 doesn’t have headlight relays? Ok, maybe there are relay spots in the PDC I can use.

As for the ICVR, just go to Electrical/ICVR.

Gary, when we get back later from Onancock I will scan the fusebox portions of both the PDC and dashboard ones. I think there is a dedicated headlight switch feed. If you need it I can get voltage readings for you at the battery, PDC, headlight switch feed and right headlight (one furthest away) both low and high beam engine at idle. I know there are several large infeed wires in the bulkhead connector.

[85lebaront2]

Gary, when we get back later from Onancock I will scan the fusebox portions of both the PDC and dashboard ones. I think there is a dedicated headlight switch feed. If you need it I can get voltage readings for you at the battery, PDC, headlight switch feed and right headlight (one furthest away) both low and high beam engine at idle. I know there are several large infeed wires in the bulkhead connector.

Scans of 1986, 1990 and 1996 fuse panels emailed to you.

[Gary Lewis]

Scans of 1986, 1990 and 1996 fuse panels emailed to you.

Got them, thanks. Will peruse things tonight. Had an unexpected trip this afternoon to go get a new trailer. 😉

[Gary Lewis]

Gary, when we get back later from Onancock I will scan the fusebox portions of both the PDC and dashboard ones. I think there is a dedicated headlight switch feed. If you need it I can get voltage readings for you at the battery, PDC, headlight switch feed and right headlight (one furthest away) both low and high beam engine at idle. I know there are several large infeed wires in the bulkhead connector.

Bill - I’ve now had a chance to look through the scans you sent. I didn’t find a headlight switch feed, but maybe I’m looking in the wrong place. Or, don’t understand what you mean. Are you saying the headlight switch feeds the computer? I went through the “EVTM” drawings that Ray sent and didn’t find any headlight input to the computer there either.

And, speaking of those “EVTM” drawings, they are a help, Ray. But they aren’t quite the real thing as they leave off the header that would have been on the EVTM’s page that tells you the application. For instance, there are two pages of schematics for the fuel injectors - one is bank-fire and the other sequential. And there’s no indication which is for what engine/application. But, I thank you very much for getting them for me. They are a big help in understanding things, but I’m hoping that Bill’s actual ‘96 EVTM will help even more.

Back to the computer inputs and outputs, I did find an input from the brake switch, which I’ll have to provide. And one from the A/C system, which I assume is to tell it when the clutch is energized. And, I found a knock sensor input - that may be handy.

But I didn’t find an output to cooling fan relays. Doesn’t the computer do that?

I think what I’m going to do is to create a spreadsheet of all of the EEC-V’s inputs and outputs and what I’m going to do with them. And I’ll post that on my EFI For Dad’s Truck “whiteboard” so we can kick it around and finally get it right.

[ArdWrknTrk]

Bill - I’ve now had a chance to look through the scans you sent. I didn’t find a headlight switch feed, but maybe I’m looking in the wrong place. Or, don’t understand what you mean. Are you saying the headlight switch feeds the computer? I went through the “EVTM” drawings that Ray sent and didn’t find any headlight input to the computer there either.

And, speaking of those “EVTM” drawings, they are a help, Ray. But they aren’t quite the real thing as they leave off the header that would have been on the EVTM’s page that tells you the application. For instance, there are two pages of schematics for the fuel injectors - one is bank-fire and the other sequential. And there’s no indication which is for what engine/application. But, I thank you very much for getting them for me. They are a big help in understanding things, but I’m hoping that Bill’s actual ‘96 EVTM will help even more.

Back to the computer inputs and outputs, I did find an input from the brake switch, which I’ll have to provide. And one from the A/C system, which I assume is to tell it when the clutch is energized. And, I found a knock sensor input - that may be handy.

But I didn’t find an output to cooling fan relays. Doesn’t the computer do that?

I think what I’m going to do is to create a spreadsheet of all of the EEC-V’s inputs and outputs and what I’m going to do with them. And I’ll post that on my EFI For Dad’s Truck “whiteboard” so we can kick it around and finally get it right.

Pretty sure the computer *grounds* the relays.....

Any interest in my '87 EVTM?

I know it's outside the scope of the site.

[Gary Lewis]

Pretty sure the computer *grounds* the relays.....

Any interest in my '87 EVTM?

I know it's outside the scope of the site.

Grounds the fan relays? I thought so too but haven’t found it. Having said that, I remember something about that feature being in the code, but that it is turned off in some vehicles and there is no wire for that pin/output. So, since the “EVTM” that Ray sent me is specific to trucks it may not show those outputs if they weren’t used. That’s another good reason to map out every pin - when there are gaps maybe I can figure out what goes there.

As for your ‘87 EVTM, I would like to have it. I probably won’t put it up on the site as I’m worried about getting too much content that could cause someone to yell foul. But, it would be a good resource and I could post a clip from it when needed. If you want to send it I’ll scan it and put it back for future use - and send you a copy as well.