Ok, I am learning exponentially right now.... I found a site for checking testing the EEC & FP Relays, whichis wheat I have been using. I I have been basing my Pin #1, #2, #3, and #4 off thst site... When I look at that site, and then at the schematic on the Relay I am not sure if they match exactly..

(Here is the site: Part 3 -How to Test the Ford Fuel Pump Relay (Green Relay))

Right now I can get the power out to the FP Relay but for some reason power comes in now on the tan/gr as well. I pulled both wires from the inertia switch, (brown takes power in, and pk/blk goes to the pumps) and both wires are hot (have current) I did not think the PK/BLK should have power unless it comes through the inertia switch. I am going to get a new FP Relay pigtail tomorrow, the current one is starting to look tore up..

The only other electical change I have made/done since reattaching the harnesses, is I bought a new COIL Pig tail and wired it in. The old one was broken and the wires just fell out...causing no spark. I "Think the two wires are connected correctly" but they had fallen out before I noticed so I am not 100% sure. Is there a way to check if the wires are connected correctly? There ar only 2, and one has the Noise Capicitor on it...Not sure if that could be contributing if it is not right, but on the harnesses I fixed several cut lines, cleaned all connections and resealed them... but that was really the only connector that was bad to the point of needing to be replaced. When I get this figured out I am going to have a huge weight off my shoulders... I like fixing my old trucks, and I like to keep them as original as possible... Someday I am going to take a class in electronics/diagrams so I can understand this part of my truck.... It can be very frustrating!

 

Thanks, Fords4Me! Yesterday I ran a new (Brown wire from the relay (Power out to the Inertia Switch/Pump) I also opened the witring Harness up between the relay and the ECM/EEC and inspected the Tan/Green wire. Other than the one break (you found) I do not see any other breaks or signs of overheating. I am going to test the ground (ECM/EEC) today and also the check for the Ohms on the pump lines themselves, once I repair the Pk/Blk lines going to the pumps. Last night (just for something to do) I hooked up power to my power seat to check that it works). It worked fine! I drilled my holes for the floor mounting and will do the final install when I actually get the carpet installed. At least one thing was easy! I will let you know how it goes. Thanks for the help, hope the bench works well for you.

 

good deal. I do think new wire from relay to inertia switch, and inertia switch to pumps will go a long way towards resolving this for you. Once that is in place and wires restored to relay it "should" work.

I am still concerned with no ground from ecu. Once all is normaled if it it doesn't run for 3 seconds or so when key is switched to run, start looking at #22 and the wire to it. Make the pump run from test connector AND meter #22 to relay. If that's all good time to get busy searching for an ecu.

Pleasure meeting you. Got to Harrisonburg that night to help my child with the flat on the side of 81, and there was no spare and no lug wrench. Arrrrrrggh!

Also the ecm output to the relay doesn't have enough capacity to to hurt the wire. Instead it blows the trace on the circuit board. Repair is possible with a good eye, patience, and a soldering iron. I haven't done it or had to.

 

Glad to hear all went well with your daughter, Albeit minus a few necessary items.. LOL, Anyway, I'll keep you posted on how it goes....

 

OK all it has been awhile. Since we last talked I determined that my computer was in fact bad and I have purchased a new one. The weather has been bad here most of this spring and I have not worked on it much. I did however pick up a cheap radio and some speakers and wired them in. I noticed however that the switched power cuts out (ends) after I moved the steering wheel. Then I noticed that the yellow power (switched power) to the Fuel pump relay stays on all the time, when the battery is connected. I have not installed the new computer and don't plan to until I figure this one out. But I think the issue may be the Ignition Switch, or (lock cylinder) I just started to look tonight. Any thoughts?

 

yellow is not switched, it's hot at all times.

 

Also, red is +12 with the key in start or run
t/lg is the relay ground and is switched by the EEC
brn to the pump(s)

 

Thanks guys, yes I know the wires, brown goes out to the inertia switch, red is power from EEC Relay to the fuel pump relay, tan & green is the EEC control and (Both) yellows are ignition fused. (I misread the FP Relay) The blue&white is power from the switch black chassis ground... OK so I have poer on both Yellows, I have power on Blue & White when switch is on, red has power from EEC Relay to the FP Relay. SO I replaced the brown wire from the round connector in the firewall to the inertia switch, and the pink & black from the Inertia switch to the round connector (they melted when I had the shorting issue) Now I do not have the EEC in the truck, but when I turn the switch off I still have power on the brown line coming into the inertia switch. Shouldn't that be deas when the switch goes off?

 

What are you checking for power with on the brown wire. You should use a loading test light (no LED) and not a meter in this circuit.
A meter will show power here when you have none with the key on.

Not sure with the key off but I would think the IDM would not put power on the brown wire with the key off when checking with a meter and if it does the reading should be about 7volts.

Both relay should be at rest with the key off so no full battery power on the brown wire.

 

double check relay wiring. is the power gone if you pull the relay from the socket? The pump(s) should bleed any transient power to ground if wiring and pump is good. Without the computer the FPR should not close unless you ground the test connector

 

Ok, First question, I checked yesterday with a test light only, ground it to the frame, touch brown connector light came on, I wasn't expecting that. I checked the relay and I am getting about 9 volts on the yellow feeds, (the battery hasn't been charged nor the truck running in over 5 months so I think I need to charge the battery a bit. BUT the relay should not be feeding the brown wire unless the key is on, correct? On the fuel pump relay it is controlled by the tan-green wire from the EEC, BUT the EEC is not in the truck right now so it cannot have any power coming in... My interpretation. 2nd question, Yes, when I pull the relay I get no power on the brown wire. I also held the brown wire to the Pink/Black to see if it would trigger the pump it did not. Not sure if it is low voltage or bad pump. THe pump could have been shorted when I was working on it back in December... not sure. I was going to make a hot line (12v) and run to the pump to check... If I do this should work correct? The pink/black line comes out of the round firewall connector and I believe splits into two wires going back to the pumps, I am thinking that the high pressure pump won't work without the EEC because the EEC controls it, is that correct? I know some of these questons sound simple, but I want to make sure I have everything figured out before I put the new EEC in the truck. I don't want to blow $180.00 because I was in a hurry, By the Way, THANKS for all the help and Information.

 

So if the power is gone on the brown when the relay is pulled than the problem is in how the relay is wired or it is stuck closed. You're right on the relay not feeding the pumps unless the ECM is connected. The key switch will give the +12 FPR coil BUT the ground comes from ECM pin 22, which is why there is a test connector to manually ground this so you can test.
Brn to pnk/blk would bypass the inertia switch. Your meter should tell you if the switch is good.
Yes you can just run a hot wire to the pump and see if it works if you USE A FUSE. 9 volts from a 12v battery will have all the power of a pop corn fart. It's rain today so charge up the battery if you can. If you had power leaving on pnk/blk and the pump didn't run either the battery is too dead or there is something else happening. I would start with getting the relay right first and then the inertia switch, and after that worry about the wiring to the pumps if neither one runs.

 

Hey, Thanks for the "Pop Corn Fart" comment, my son got a kick out of that one! LOL.. Yes, that was what I was thinking. I am going to charge it on my trickle charger today, and just check to ensure what I told you is all holding true, I am also going to measure the power on the Brown wire (feeding the Inertia switch) if it is the same as the power leaving the Fuel Pump Relay then I think those wires are good and have been repaired correctly. Assuming we see any sunlight at all tomorrow, I will test my pump just to see if it kicks on. Once I have done that, and know the pump is working, battery is charged and power from the relay to the inertia switch is good, I will put the computer back in. I am also going to check my Ignition switch because whenever I jar the Steering column the "Idiot" buzzer comes on... But when I turn the switch off and remove the key it goes off, (as it should) but will not come back on when I insert the key... until I jar the Column. So I think something is loose. Like I said. I want to work out every bug I can before putting the computer back in. Everything else electrically seems OK. The radio is acting up but I bought it used "cheap" so I don't know if it is the radio or power. I have "Yellow" constant power and switched power as well, but I need to see if the switched power remains after a few minutes, (the radio shuts down) if the switched power is still present, then its the radio... I only bring it up because combined with the "Idiot" buzzer that makes two intermittent issues that could point to a faulty/loose switch or connection. Oh I do so love wiring.... NOT! Thanks again.

 

OK, its a rainy damp cool day ... with no garage... so I didn't do much, but I did install the computer, and I put the sterring column back up and tightened it. Voltage at the Battery is reading 9.74, so I will leave it on the charger tonight. I checked the voltage at the relays just to see what it was and it was 9.57 and 9.71 so it's almost what the battery is reading so I think that is ok. But I did not get power at the brown wire in the interior (Inertia Switch) so I checked the relays. No power from EEC Relay to FP Relay, all power showing up at the right places going into the relays just not coming out. I jumpered EEC relay from yellow hot to Black/yellow out to FP Relay and then I got power at the FP Relay on the red line. as it should be. I then jumpered the yellow hot FP Relay to the Brown OUT line and got power there. Relays all bad? Can they stick and then be unstuck? If not I will need to get some new relays. Radio still comes on sometimes and then just shut off but all other dash lights and functions seem to be ok. I think it may just be the radio, but I am going to pull it tomorrow and check the switched voltage to see if it stays on or if it dies. If it dies I have another issue somewhere. If it staays on then I believe the problem is just the radio.

 

UPDATE: Ok, raining like cats & Dogs here, I put the charger on yesterday, its now up to 12.89 so that is good. I checked power at the relays, Both yellow showing 12+, when the switch is on I get 12+ on the Bl/Wh BUT I am not getting power out of the relays... either one, When I jumper the EEC Relay I get power out, same with the FP Relay. I can't imagine both going bad at the same time, but power going in seems fine, when I jumper either one I get power out (like I should) I am going to get some new relays this week and try next weekend. Now that the steering column is back in and tight, the radio comes on (as it should) I think maybe the low battery was partly to blame. I will still jumper the Pump later this week, it's just too wet out there righ now. Wish me luck and thanks for the help!