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Unread 10-30-2013, 10:02 AM   #61
flipit
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Quote:
Originally Posted by laybackman View Post
That portion of the DKGN/YL wiring in the Mustang wiring diagram that shows power going through the inertia fuel shut-off switch has probably been eliminated and your green jeep wiring is spliced to it at that terminal board on your firewall
this is true.

wire 19 comes out of pin 19 and is SPLIT. wire 19.5 goes straight to the terminal board, wire 19 goes...somewhere...

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Unread 10-30-2013, 10:06 AM   #62
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Quote:
Originally Posted by laybackman View Post
So, if you turn the ignition switch to START or ON that green wire in the fuel pump plug at the gas tank should have 12 volts. If not and you have 12 volts at the terminal board feeding that green wire that green jeep fuel harness wire has a break in it.
can we reverse this?
i have 12 volts at START, and ON, and RUN, and OFF, and LOCK, and ACCESSORY, and at KEY OUT OF THE JEEP-

so, going with you (I) should not have 12v when the jeep is off, but only at start or on... and since that is not the case what you are saying is there is a break in the green/yellow wire?
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Unread 10-30-2013, 10:08 AM   #63
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Originally Posted by flipit View Post
So it's not just me, good to know.
Trust me when it comes to being completely and totally 'wet', I have been down that road so many times I don't even bother 'drying off' anymore......
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Unread 10-30-2013, 10:08 AM   #64
flipit
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Quote:
Originally Posted by laybackman View Post
Maybe I am completely wet here but from what I can see the PNK/BK wire is a constant 12v source for fuel pump power BUT is also controlled by the position of the inertia switch. The fuel pump relay is powered by the YL wire BUT is controlled by the PCM power relay to close (turn on) power to close itself and the fuel pump relay also.

Is the LT BLU/OR wire do going to pin #22 the clutch pedal or NSS switch the the ground you want to see?
i thought pins 20, 40, 60, and 49 were the grounds?\\**nevermind- ignore this.
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Unread 10-30-2013, 10:17 AM   #65
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Originally Posted by Que89YJ View Post
LOL Layback you rock. Looked at it and you are 100% right. I think I had too many Jamesons last night! Pin 19 still cannot be power. It must be a sense line because it would be hot all the time and give constant power to the pump. It isnt the control line, pin 22 definitely is. Why is there 12 volts on pin 19? Is it spliced somewhere? Layback you nailed it! Flipit, we need to make sure that the line is power going to the tank from that terminal block and the wire and if it is where is the wire it connects to on the terminal block getting power from.
You dont ever hear me admit to this and if you tell the GF I will deny itbut I was wrrr.....wrrrrr......wrong ok! LOL
okay okay, so the way i understand this- when the ignition is turned, the pcm power relay links the yellow wire to the red wire, making power go to the fuel pump relay, which functions, by going through pinn 22 and completing a circuit, and flipping the relay, creating a full circuit from pink/black to green/yellow- sending power- into the ECU, also, there's a green and yellow stem off, which sends power to the fuel pump.

so, my wiring is ALL CORRECT,
except,
somehow
The green yellow wire is getting power at all times,
instead of when it's "allowed to"
so i need to find the gremlin whos giving it power now?
and bypassing the relay.
and possible faults could be...???
a short?
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Unread 10-30-2013, 10:18 AM   #66
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Quote:
Originally Posted by flipit View Post
can we reverse this?
i have 12 volts at START, and ON, and RUN, and OFF, and LOCK, and ACCESSORY, and at KEY OUT OF THE JEEP-

so, going with you (I) should not have 12v when the jeep is off, but only at start or on... and since that is not the case what you are saying is there is a break in the green/yellow wire?
Look at the diagram. There are two 12 volt wires to look at the PNK/BK wire that feeds the starter through the relay and the YL wire that feeds power through the PCM power relay. IF the fusible link ins't broke and is still there they should have 12 volts.

We=hen you turn the key to START you add ground tho that circuit close the PCM POWER RELAY and allow the fused link PNK/BK wire to send 12 volts through the relay to the fuel pump. I think you can ignore that Inertia Fuel Cut Off Switch since that is in the dash board of the Mustang

On yours I think they have the GRN/YL wire stuck on the terminal board and the Green wire from the YJ harness wired directly to it at the terminal board. It should be going through a relay.

How long have you owned this YJ with the 5.0 swap in it? Do you have the Mustang fuel pump relay under the hood of the YJ as part of the Mustang engine harness?
THAT is what I would be looking for. The fuel pump should not be 'hot' all the time.

Keep in mind a relay simply put is a cheap device that is nothing more than a heavy duty switch.

One side provides power for the device you want to turn of/off the other side is power to close/open the relay to allow that to happen.
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Unread 10-30-2013, 10:31 AM   #67
Que89YJ
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That is what we were talking about. I just got 19 confused with 22 and I still dont know where the pump power is coming from and what else is on the terminal strip. A fuel pump relay and an asd relay is a must. The pdc is there, the question is what to wire to what.
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Unread 10-30-2013, 10:34 AM   #68
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Quote:
Originally Posted by flipit View Post
okay okay, so the way i understand this- when the ignition is turned, the pcm power relay links the yellow wire to the red wire, making power go to the fuel pump relay, which functions, by going through pinn 22 and completing a circuit, and flipping the relay, creating a full circuit from pink/black to green/yellow- sending power- into the ECU, also, there's a green and yellow stem off, which sends power to the fuel pump.

so, my wiring is ALL CORRECT,
except,
somehow
The green yellow wire is getting power at all times,
instead of when it's "allowed to"
so i need to find the gremlin whos giving it power now?
and bypassing the relay.
and possible faults could be...???
a short?
Actually the LT BLU/OR wire MAY BE a ground source for the NSS or clutch pedal switch. Unless it is in park/neutral or the clutch is pressed in the engine won't start since the PCM relay can't close.

When they get engaged, the circuit is complete on THAT SIDE of the relay allowing the other side of the relay to close sending power to the fuel pump relay and on to the fuel pump!

But the fuel pump relay doesn't seem to be part of your wiring .
See where the LT BLU/OR wire coming out of pin #22 goes.

Just for clarification. If you check the green wire in the YJ fuel pump plug at the gas tank even if there is no key in the ignition you have 12 volts?

If that is so you need to install a relay in that circuit! That constant voltage would certainly kill the fuel pump since it never shuts off and must kill your battery often.
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Unread 10-30-2013, 10:37 AM   #69
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Quote:
Originally Posted by laybackman View Post
Look at the diagram. There are two 12 volt wires to look at the PNK/BK wire that feeds the starter through the relay and the YL wire that feeds power through the PCM power relay. IF the fusible link ins't broke and is still there they should have 12 volts.
RIght, but it wouldn't send the volts though if the key wasn't on, cause of the pcm relay...and both would have to have 12v for my green/black to have 12 volts

Quote:
Originally Posted by laybackman View Post
We=hen you turn the key to START you add ground tho that circuit close the PCM POWER RELAY and allow the fused link PNK/BK wire to send 12 volts through the relay to the fuel pump. I think you can ignore that Inertia Fuel Cut Off Switch since that is in the dash board of the Mustang
i don't have that switch yes, It was not on my dash.

Quote:
Originally Posted by laybackman View Post
On yours I think they have the GRN/YL wire stuck on the terminal board and the Green wire from the YJ harness wired directly to it at the terminal board. It should be going through a relay.
that is all true.

Quote:
Originally Posted by laybackman View Post
How long have you owned this YJ with the 5.0 swap in it? Do you have the Mustang fuel pump relay under the hood of the YJ as part of the Mustang engine harness?
THAT is what I would be looking for. The fuel pump should not be 'hot' all the time.
5 years
no, the fuel pump relay is from the wrangler, and currently bypassd.

Quote:
Originally Posted by laybackman View Post
Keep in mind a relay simply put is a cheap device that is nothing more than a heavy duty switch.

One side provides power for the device you want to turn of/off the other side is power to close/open the relay to allow that to happen.
true. it is a control to regulate when something goes off and on, and right now, mine has no control.
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Unread 10-30-2013, 10:39 AM   #70
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Quote:
Originally Posted by Que89YJ View Post
That is what we were talking about. I just got 19 confused with 22 and I still dont know where the pump power is coming from and what else is on the terminal strip. A fuel pump relay and an asd relay is a must. The pdc is there, the question is what to wire wo what.

"The pdc is there, the question is what to wire wo what"



And that is the $64,000.00 question!!!!!!

If the fuel pump is getting constant power it won't live long and the OP
couldn't keep his battery charged!

flipit; Was this YJ a recent purchase??
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Unread 10-30-2013, 10:42 AM   #71
Que89YJ
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He bought it before he went active duty and parked it for a few years! He's a Jar Head and damn proud of it.
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Unread 10-30-2013, 11:13 AM   #72
flipit
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Quote:
Originally Posted by Que89YJ View Post
That is what we were talking about. I just got 19 confused with 22 and I still dont know where the pump power is coming from and what else is on the terminal strip. A fuel pump relay and an asd relay is a must. The pdc is there, the question is what to wire to what.
okay, I got an idea...
haha,
we are guessing a lot.
or, well, you guys are guessing and i am just creating more chaos.
so I'm going to go chase wires.
I will then give you as much info on where every wire goes as i can.

And laybackman,
I have owned this jeep for five years, I purchased it in 08,
I ran it how it was, until i broke it,
then after years of generating funding,
it is now my ultimate goal,
to make this thing a real toy.
a properly working, fully functioning,
sensibly equipped machine!

haha, but really,
the pump went out in 09,
I bought some used axles in 12,
and starting this summer,
I have been rebuilding it,
if you look at my profile pic,
that is not the current condition,
i put the axles back on and moved it in the shop,
I'll update that as soon as I don't have more pressing things going on...
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Unread 10-30-2013, 11:43 AM   #73
flipit
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okay, starting off, this is my engine compartment,
here is all the stuff



and this is the current condition of my interior-



please not, unless i say otherwise, during all testing,
this is the current position of the key



and in case there are any questions about the quality of this job,
this is under my battery...

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Unread 10-30-2013, 11:59 AM   #74
flipit
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okay, for this journey,
I'm going to start it off nice and easy-
these three wires connect to the fuel pump connector-



now, from bottom to top-
the ground wire,
note the color, black, with an orange stripe,
goes into the bay, and is screwed into the firewall here.
not the yellow crimp, kinda hard to see i know-



if there's a break in this wire, It touches another grounding point,
cause to the best of my knowledge this line works as advertised.

next up is the gauge,
most of the way up the line,
he cut the dark blue cable and spliced it,
then re spliced it at the end,
shown by the following pictures...




this line as well,
when the jeep started up, the tank was always 1/4 tank high, but it did work.

now for the painful wire,
dk grn/blk...

that cable makes a snug, straight shot here-



bottom right of terminal board-
then,
top right,
green/yellow, goes into here..



the excess is zipped tied,
and the end is add-a-spliced here.



if you follow the stock green/yellow, it is pinned on one side via the connector,
and the other goes into pin 19 of the ECU...



while undoing the wiring harness i found these two open wires...

and this guy is pin 22.

if i have the time, I can make a wiring diagram for all that,
but honestly i think that describes it well.
what else should i chase?
you want me to remove the ECU plug and see if 22 is coming in hot?
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Unread 10-30-2013, 12:04 PM   #75
Que89YJ
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If that PDC harness is there you are in good shape. The pump failed because of continuous power. Figure out what is powered on that strip and from where. You should have auto shutdown relay power going to the injectors, coil and switch ignition power into the ecu and O2 heater. The fuel pump should be on a second relay. That wiring diagram Labackman posted is perfect. If you have that with the FSM In Morris4x4 you should be able to figure it out with his help. I am just confusing things so I am taking a back seat on the thread. Layback has it right and did all along.
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