Thank you Stan, that answers what that relay is for, but it does not answer
why it is now clicking when I ground the fuel pump relay, when it was not
clicking before. I think that when I force ground the fuel pump relay, a
circuit is being, at least partially, completed that had not been completed
before with the tan lt/grn wire attached.
I knew about greasing the speedometer cable, but just hadn't done it. I was
just bringing that up because I may have been misinterpreting a symptom.
One last thing. I can not find a cross matched number for the relay in the
passenger side kick panel. The second number is rubbed off a little, but I
tried different variations of it. Still couldn't find it. It looks like
E3AB-14512 or E7AB-14512.
Take Care, Sharon
I'm no electrical guru Sharon, but I've owned a lot of old cars. When all
the components check out as good, replace the wiring. I had a charging
problem on a 79 Mustang where everything checked out, including the wiring.
Replacing all the wiring in the circuit cured the problem. On older cars
wiring can be broken inside the insulation, it can get corroded and set up
high resistance, and it can develp intermittent grounds. When all the relays
etc. are working properly, the only thing left is the wires. Get an
assortment of wire sizes and colors and make a diagram as you go showing
what color goes to what. (If you own the car long enough, you'll need the
diagram again.) And as far as finding and replacing the one wire with a
problem goes- they're all the same age. Might as well replace them all while
you're there. If you have to splice to reuse connectors, solder and tape
then shrinkwrap the splices. Solder won't come apart the way other
Wishing you luck with this,
Every day is a good day- it's just that some are better than others.
I agree with you Max. I think wire breakdown has definitely started. I
will do what Thomas told me to do to check out that secondary circuit, with
the primary wires connected and see what happens with the test light. Then
with the forced grounding on the tan wire and see what the light does on the
My next step will be to check out, thoroughly, all grounding wires. I will
start at the front and work backwards. I am lifting out the back seat to
check the fuel pump grounding wire all the way through too. It seems to go
through there. I got to thinking - I had that car loaded down with a lot of
things in that back seat during that cross-country trip. I had very little
clearance in those rear wheel wells. It could be that the weight on the
back seat pinched a wire causing a slice in the insulation of the wires that
go through there.
I found another piece of insulation worn away on a wire in the engine area
today. That is the fifth wire I have found. I looked that wire over well
just a couple of days ago. So, it seems that plastic insulation breakdown
is for some reason escalating. I think the dry heat here has finally caught
up with the car. Specifically in the engine area, where it is even hotter.
And maybe the heat of the high speed driving on the trip sped the process
up. Not a good situation.
This is a new experience for me. In NY we worry about rust, not plastic
breakdown. In AZ, the heat causes a real breakdown of the vinyl and plastic
parts. I noticed it on the interior first. It is kind of like rust. One
day the part is stable and usable, a week or so later it can develop a whole
and start falling apart. Seems like the same thing is happening here with
the plastic insulation in my engine. Maybe I should contact one of my
friends in NY and see if they can get me some complete harnesses from the
junk yards back there. LOL A junkyard dealer here already tried to sell
me one cheap ($10), but it would have the same breakdown problem. That
would be like setting a $10 bill on fire deliberately!
So tomorrow, my job will be to check and recheck wires. Stan and Bee Vee
sent me some invaluable wiring diagrams today. Thank you sooooo much guys.
This is what I have been asking to get all along and it is going to help me
with this process a great deal. I really appreciate the trouble you went
through to get them for me. Thanks.
Take Care, Sharon
I called up the Ford dealership in my town. The one that my neighbors told
me to stay away from. Now, I understand why. I asked them to see if they
carried a fuel pump relay and a relay socket for my car. They told me that
my car does not have a fuel pump relay. That the only relay in that fender
area, for my car is the engine control relay. I told them I had several
relays (fuel pump, wide open throttle, engine control), but they argued that
I did not. So much for Ford service here.
I really don't like you using an analog meter, but........ it's what you have
First as I said set it to the lowest setting, that would be the one on the
bottom X1, which means times 1. The next setting is X10, that is times ten. The
next setting is X1K The K is 1000, so it would be times 1000. 1k is 1000, 10K is
Now you know what the settings are and how to interpret the readings. Before you
can use this meter to read OHMS you must calibrate it. Set the knob to what ever
range you are using. Take the test leads and touch them together. Use the red
wheel and 0 the needle. You are now ready to use the meter. Be very careful to
not touch the red wheel, as that you will go out of calibration. So set the
meter to the X1K range. I'm not sure if the meter has the range to work or not.
Before we go there, does the car run when you jumper the yellow wire to the
Thanks Thomas. I am using this meter (not the one Stan published):
On the RX10 setting (that is what you originally told me to do), with it
calibrated. Here are the readings I am getting:
At rest (no key in the ignition), 3 on the meter consistently.
Key in 'on' position only, just one mark below 3.
Key in 'start' position, just one mark below 5, then when turned off goes
back down to one mark below 3.
Take Care, Sharon
Sharon, I dont trust what your reading. It is the wrong meter for this. All this
shows is that the transister is changeing states, nothing more. It does not show
if it is makeing ground, which I suspect it really is.
Do this for me. Put the red wire on the relay where it is supposed to go to. The
terminal that you would attach the tan wire? Do not put on the tan wire, but put
the red test lead to the relay terminal instead. Put the other test lead to
ground. Turn the key run. Do you show 12 volts? ( first verify that you have 12
volts at the red wire. ) You should have 12 volts at both.
Sorry Thomas, I had another situation to attend to. I checked the volts on
the red wire in the start position. On my scale, it reads a little over 12+
volts coming through when I put it on the 10 setting. That would be
reasonable. Then I connect the red wire to the relay, put the positive lead
on the tan wire and put ignition on start. I show a little over 12+ volts
all the time I am cranking. I hope that helps you to see what it is doing.
Thanks sooooooo much for trying. Take Care, Sharon
Now take a wire attach it to the terminal that you would install the tan wire
and to ground, just like I wanted you to do with the meter to test for 12 volts.
Put the other end to a ground ( key on ) does the relay click and pump run? (
obviously the yellow and orange wire should be on their correct terminals ) The
only wire not installed is the tan wire.
Sorry, I didn't see this post until after I responded to your other post.
Okay, let me just clarify this. Hook all three wires to the relay (orange,
yellow, red). Then hook a wire up to the last nipple of the relay and
attach it to a good grounding spot, instead of installing the tan wire? Do
you want me to put the tester to any of these wires? Or just try it with
Take Care, Sharon
Practice time :
If I'm reading Thomas' instructions correctly, you are to put the
meter from that grounding wire to a ground. In other words, you are
repeating the same test as before (with the tan wire disconnected) but
the only difference is you have grounded that terminal on the relay.
I believe you should read no voltage this time, and the fuel pump
should be running.
Theory time :
Voltage is technically termed "potential difference". It is the
difference in potential between two points. If the difference is
greater than zero, then you have power, potential energy, that is
capable of doing "work". If your potential difference, or voltage, is
zero then you have no power, no potential energy.
Applying the theory :
With the relay's primary circuit disconnected (tan wire disconnected)
you have 12 volts of potential difference between that and "ground".
Ground is, by definition, zero potential. It is your reference point.
Having 12 volts there means that if you connect that circuit to ground
(thereby completing the circuit) you can achieve some work being done
by the electricity. In this case the work is closing the relay's
contacts to that the secondary circuit is completed (closed). When
you connect that terminal to ground, it then has the same potential as
ground (naturally, it's connected). That is why I expect you to read
zero volts while doing this test, and why I expect the fuel pump to be
Combining these two tests allows you to determine whether or not the
relay is functioning as it ought to be. In any set of tests, you must
have isolated precisely one variable in order to draw any conclusions
from them. The isolated variable here is whether or not the primary
circuit on the relay is closed.
Emacs is a nice operating system, it lacks a decent editor though
In simple terms, you are describing "voltage drop". A voltage drop is the amount
the voltage lowers when crossing a component from the negative side to the
positive side in a series circuit. Voltage applied to a series circuit is equal
to the sum of the individual voltage drops.
In this case the resistance of the fuel pump relay coil ( industry average ) is
80 ohms. 12 is the working volts. So the current will be .15. 12/80=.15 amps (
The voltage drop is calculated as current x resistance = voltage drop.
.15x80. So if the voltage is dropping 12 volts and you start with 12 volts,
you see 0 on the ground of a completed circuit. Current will be .15 on the whole
circuit. It does not change.
Here is the odd thing I have been trying to figure out since trying this. I
put the wires on all the connectors, except the tan one. I put an alligator
clip to that connector of the relay and the other end was clipped to the
alternator housing to insure a good ground. When I turn the key to 'on'
only, I do not hear the relay click, but I do get a clicking noise in
another area of the car. I also do not hear the pump run. When I put the
key to 'start' and try to crank the engine, I get nothing.
About the clicking noise I am getting while in the 'on' position when doing
this test. It is located on the passenger side. I can hear it with the
passenger door open very well, but when I go to the engine, either above or
under the car, I can't hear it as well. And I can hear it through the glove
box okay, but again not as well as through the door crack. I have taken a
digital pic and put a section of garden hose in where I heard the sound
That is the passenger side door and that hose is inserted just about 4
inches into the fender area. That seems to be where it is the loudest. I
hope that helps. Thanks Thomas. I am pretty much staying focused on what
you are telling me and trying to follow this through with you. Thank you
for hanging in there with me, regardless of all the hurdles.
Take Care, Sharon
I just want to make sure that you are reading the meter corectly.
When you say the meter shows 12+ volts on the 10 setting, is the needle off
the end of the scale to the right?
DCv 10 is 0 to 10 volts dc and the DCv 50 would be 0 to 50 volts dc .
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