Fuel Pump getting 5 volts

OTreborO · August 9th, 2006, 09:06 AM

I thought I had a fuel pump problem, but found out I am only getting 5-6 volts when I turn on the car or when I crank the engine. I checked the inertia switch, it is good, and also getting 5 volts there as well. Any ideas as to why I am only getting 5-6 volts???

Thanks,

Trebor

stang fanatic · August 9th, 2006, 10:24 AM

ck the relay.

OTreborO · August 9th, 2006, 10:00 PM

where is the relay? I thought it was under drivers seat, but found out that was an a/c relay

TENGRAM · August 10th, 2006, 02:43 AM

Originally Posted by OTreborO

where is the relay? I thought it was under drivers seat, but found out that was an a/c relay

the one under the seat is the fuel pump relay. its identical to the a/c relay.

C MY 4D · August 10th, 2006, 03:14 AM

on your 89???? If so I concur with what they said yank the seat out and check the voltage there.

OTreborO · August 10th, 2006, 09:18 AM

I went to autozone and they looked up the part number and told me it was an A/C relay, then they showed me other relays for the fuel pump. One had too many prongs, the other had the correct amount of prongs but did not have the same shape as the Ford relay, the Ford relay had a bump/hump molded into one side, the replacement was square, but it should plug in.

I got 12V on one of the wires, I think it was Orange, and I got 6V on 2 of the wires, and I think 3-4 volts on the other wire.

ugh.............................................

OTreborO · August 11th, 2006, 02:15 PM

Relay didn't fix the problem:

looks like 12V on orange wire and 4-6 volts on the other wires at all times

Any suggestions??????????????

Thanks in advance

BTW, The relay I got had an extra terminal on it, but I was told it was the replacement, apparently this one relay works on a lot of applications???

anybody have a good schematic of the fuel system electronics

One other side note, kind of funny, but hopefully not related is that when I turn on the right blinker the speedometer flashes

Seriously, the blinker works just fine, front and rear, but the light on the left side of the speedometer flashes instead of the blinker indicator LOL
Also the hazard flashers don't work, but that is probably because of the weird blinker

stang fanatic · August 11th, 2006, 02:41 PM

thats interesting cuz the f/p relay is behind the p/s kick panel by the computer

stang fanatic · August 11th, 2006, 02:44 PM

'89 with 4 cyl. had blk/org=12 volts at all times; red/blk switched power through inertia switch from ecc power relay; tan/lt grn to the eec; pink/blk to fuel pump

OTreborO · August 11th, 2006, 04:01 PM

I was told the relay is under the drivers seat????????????

Oh my, I am so confused. I am ready to scream guys................

Some one please just kick me in the nuts

If I had 6 volts at the inertia switch would that mean the FP relay would not be the issue, maybe a ECC relay, not that I would know where that is located

stang fanatic · August 11th, 2006, 06:56 PM

according to my book...you had a blk/org from a fusible link--eec power relay---redwire to inertia sw.---red/blk to relay.
ok...red/blk at relay should have 12 vlts. blk/org at relay is fusible linked and should have 12 volts. the blk/org is the one going to the pump. Sounds like youre fusible links may have melted

stang fanatic · August 11th, 2006, 06:57 PM

see what you have at pin #1 of the ecc. its blk/org. comes off the fusible link side of the ecc pwr relay so it should have 12 vlts

TENGRAM · August 11th, 2006, 07:15 PM

Originally Posted by OTreborO

I was told the relay is under the drivers seat????????????

some models (4-cylinders i guess) had them in the kickpanel, but all of the ones i have seen are under the driverseat...i suppose because i've never bothered to look at a 4-pot :wink . if there is a relay under your seat, it is the FP Relay.

this diagram may help you with your problem - http://www.veryuseful.com/mustang/te...ng_Diagram.gif

stang fanatic · August 11th, 2006, 07:30 PM

nice diagram...but his car is an 8 from 4 conversion, so hes looking at 4 cyl wiring which was different from the 8

TENGRAM · August 11th, 2006, 11:32 PM

Originally Posted by stang fanatic

nice diagram...but his car is an 8 from 4 conversion, so hes looking at 4 cyl wiring which was different from the 8

this is where i become useless, as i have no experience with conversion wiring/methods...but i'll exit with this: it seems as though you are getting a VREF Signal (4-6vdc) rather than the VBATT (12vdc). i suspect the problem is FP wiring from the wrong ECM pin...but again, i know nothing about conversions

good luck

OTreborO · August 12th, 2006, 08:15 PM

I have 12V at pin 1 of ECC
Now relay at ECC:
Voltages with relay connected:
all 12V except black/green has 0V

Voltages with relay not connected:
Black/Orange 12V
Red 4 V
Orange/Black 4 V
Black/Green 0V
Red/Green 12V

stang fanatic · August 12th, 2006, 11:10 PM

ok...12 volts at pin 1 means fusible link is good.
blk/grn is your ground so it should read 0 vlts.
ok...blk/orange is fusible link, constant 12.
RED is 12 volts out of relay to inertia switch.
Orange/blk...?
Black/Green is ground for coil of the relay.
Red/Green is switched 12 vlts for the coil of the relay.
Now, you sure the Orange/blk isnt blk orange? The book shows
Blk/Orange off of the fusible link to the ecc relay. A second Blk/Orange comes off this terminal and goes to the ecc at pin 1. I say its all ok.

now go to the fuel pump relay and inertia switch....
the red coming off of the ecc relay goes to the inertia switch and then comes out as red/blk and goes to the coil side of fuel pump relay.
There is a blk/orange at the fuel pump relay which is constant 12 vlts.
Tan/Lt Grn at relay is the ground side of the relay coil and goes to the ecc on pin 22.
Pink/Blk is power going to fuel pump when relay is activated.

When you are for sure you found fuel pump relay, first turn key on and plug relay in enough to make contact and then release and see if it clicks. if it does...power to pump is problem. if not relay is bad or then need to ck power there.

OTreborO · August 13th, 2006, 06:46 PM

Relay is under seat because pink wire from fuel pump goes to this relay:

Here is what I found with relay unplugged:

Pink wire going to fuel pump has 5 V, weird???
Orange Blue has 12V
Tan/Green has 6V
Red/black has 3V

I got a new relay, but it still doesn't work

The relay I got has 5 terminals, the original has 4, Autozone guy said that was ok......

Any help appreciated

stang fanatic · August 13th, 2006, 09:56 PM

okay...go back to inertia switch, wire going in is red...has 12v? it should with key on. your red/blk at inertia switch, should have 12v with key on. if not...switch is bad. if you do, and you only have the 3v at the relay...trace the wiring back to inertia switch...wire either shorting or more than likely, a connector behind one of the kickpanels is coroded.

OTreborO · August 13th, 2006, 10:26 PM

Inertia switch is ok, ohms less than 5

6V at the inerta switch :-(

August 9th, 2006, 10:24 AM	#2
stang fanatic Enthusiast Join Date: May 2006 Location: El Paso, Tx Posts: 861 iTrader: 0 reviews	ck the relay. __________________ "The gods too are fond of a joke." "If I had only known, I would have been a locksmith. "

August 9th, 2006, 10:00 PM	#3
OTreborO Enthusiast Join Date: Apr 2006 Posts: 638 iTrader: 0 reviews	where where is the relay? I thought it was under drivers seat, but found out that was an a/c relay __________________ "Those who forget the past are condemned to repeat it" Rev. Jim Jones

August 10th, 2006, 03:14 AM	#5
C MY 4D Billy Weston 2003 Cobra 11.14@124.36 Join Date: Aug 2006 Location: Hampton, VA Posts: 4,806 iTrader: 8 reviews	on your 89???? If so I concur with what they said yank the seat out and check the voltage there. __________________ TT Build in progress....... Need work done to your car for a great price in Hampton Roads? Shoot me a PM.

August 10th, 2006, 09:18 AM	#6
OTreborO Enthusiast Join Date: Apr 2006 Posts: 638 iTrader: 0 reviews	OK, I did I went to autozone and they looked up the part number and told me it was an A/C relay, then they showed me other relays for the fuel pump. One had too many prongs, the other had the correct amount of prongs but did not have the same shape as the Ford relay, the Ford relay had a bump/hump molded into one side, the replacement was square, but it should plug in. I got 12V on one of the wires, I think it was Orange, and I got 6V on 2 of the wires, and I think 3-4 volts on the other wire. ugh............................................. __________________ "Those who forget the past are condemned to repeat it" Rev. Jim Jones

August 11th, 2006, 02:15 PM	#7
OTreborO Enthusiast Join Date: Apr 2006 Posts: 638 iTrader: 0 reviews	Relay didn't fix the problem Relay didn't fix the problem: looks like 12V on orange wire and 4-6 volts on the other wires at all times Any suggestions?????????????? Thanks in advance BTW, The relay I got had an extra terminal on it, but I was told it was the replacement, apparently this one relay works on a lot of applications??? anybody have a good schematic of the fuel system electronics One other side note, kind of funny, but hopefully not related is that when I turn on the right blinker the speedometer flashes Seriously, the blinker works just fine, front and rear, but the light on the left side of the speedometer flashes instead of the blinker indicator LOL Also the hazard flashers don't work, but that is probably because of the weird blinker __________________ "Those who forget the past are condemned to repeat it" Rev. Jim Jones

Fuel Pump getting 5 volts

Fuel Pump getting 5 volts

where

Re: where

OK, I did

Relay didn't fix the problem

I was told the relay is under the drivers seat????????????

Re: I was told the relay is under the drivers seat??????????

Voltages

latest on wiring

inertia switch

August 9th, 2006, 09:06 AM	#1
OTreborO Enthusiast Join Date: Apr 2006 Posts: 638 iTrader: 0 reviews	Fuel Pump getting 5 volts I thought I had a fuel pump problem, but found out I am only getting 5-6 volts when I turn on the car or when I crank the engine. I checked the inertia switch, it is good, and also getting 5 volts there as well. Any ideas as to why I am only getting 5-6 volts??? Thanks, Trebor __________________ "Those who forget the past are condemned to repeat it" Rev. Jim Jones

August 11th, 2006, 02:41 PM	#8
stang fanatic Enthusiast Join Date: May 2006 Location: El Paso, Tx Posts: 861 iTrader: 0 reviews	thats interesting cuz the f/p relay is behind the p/s kick panel by the computer __________________ "The gods too are fond of a joke." "If I had only known, I would have been a locksmith. "

August 11th, 2006, 02:44 PM	#9
stang fanatic Enthusiast Join Date: May 2006 Location: El Paso, Tx Posts: 861 iTrader: 0 reviews	'89 with 4 cyl. had blk/org=12 volts at all times; red/blk switched power through inertia switch from ecc power relay; tan/lt grn to the eec; pink/blk to fuel pump __________________ "The gods too are fond of a joke." "If I had only known, I would have been a locksmith. "

August 11th, 2006, 04:01 PM	#10
OTreborO Enthusiast Join Date: Apr 2006 Posts: 638 iTrader: 0 reviews	I was told the relay is under the drivers seat???????????? I was told the relay is under the drivers seat???????????? Oh my, I am so confused. I am ready to scream guys................ Some one please just kick me in the nuts If I had 6 volts at the inertia switch would that mean the FP relay would not be the issue, maybe a ECC relay, not that I would know where that is located __________________ "Those who forget the past are condemned to repeat it" Rev. Jim Jones

August 11th, 2006, 06:56 PM	#11
stang fanatic Enthusiast Join Date: May 2006 Location: El Paso, Tx Posts: 861 iTrader: 0 reviews	according to my book...you had a blk/org from a fusible link--eec power relay---redwire to inertia sw.---red/blk to relay. ok...red/blk at relay should have 12 vlts. blk/org at relay is fusible linked and should have 12 volts. the blk/org is the one going to the pump. Sounds like youre fusible links may have melted __________________ "The gods too are fond of a joke." "If I had only known, I would have been a locksmith. "

August 11th, 2006, 06:57 PM	#12
stang fanatic Enthusiast Join Date: May 2006 Location: El Paso, Tx Posts: 861 iTrader: 0 reviews	see what you have at pin #1 of the ecc. its blk/org. comes off the fusible link side of the ecc pwr relay so it should have 12 vlts __________________ "The gods too are fond of a joke." "If I had only known, I would have been a locksmith. "

August 11th, 2006, 07:30 PM	#14
stang fanatic Enthusiast Join Date: May 2006 Location: El Paso, Tx Posts: 861 iTrader: 0 reviews	nice diagram...but his car is an 8 from 4 conversion, so hes looking at 4 cyl wiring which was different from the 8 __________________ "The gods too are fond of a joke." "If I had only known, I would have been a locksmith. "

August 12th, 2006, 08:15 PM	#16
OTreborO Enthusiast Join Date: Apr 2006 Posts: 638 iTrader: 0 reviews	Voltages I have 12V at pin 1 of ECC Now relay at ECC: Voltages with relay connected: all 12V except black/green has 0V Voltages with relay not connected: Black/Orange 12V Red 4 V Orange/Black 4 V Black/Green 0V Red/Green 12V __________________ "Those who forget the past are condemned to repeat it" Rev. Jim Jones

August 12th, 2006, 11:10 PM	#17
stang fanatic Enthusiast Join Date: May 2006 Location: El Paso, Tx Posts: 861 iTrader: 0 reviews	ok...12 volts at pin 1 means fusible link is good. blk/grn is your ground so it should read 0 vlts. ok...blk/orange is fusible link, constant 12. RED is 12 volts out of relay to inertia switch. Orange/blk...? Black/Green is ground for coil of the relay. Red/Green is switched 12 vlts for the coil of the relay. Now, you sure the Orange/blk isnt blk orange? The book shows Blk/Orange off of the fusible link to the ecc relay. A second Blk/Orange comes off this terminal and goes to the ecc at pin 1. I say its all ok. now go to the fuel pump relay and inertia switch.... the red coming off of the ecc relay goes to the inertia switch and then comes out as red/blk and goes to the coil side of fuel pump relay. There is a blk/orange at the fuel pump relay which is constant 12 vlts. Tan/Lt Grn at relay is the ground side of the relay coil and goes to the ecc on pin 22. Pink/Blk is power going to fuel pump when relay is activated. When you are for sure you found fuel pump relay, first turn key on and plug relay in enough to make contact and then release and see if it clicks. if it does...power to pump is problem. if not relay is bad or then need to ck power there. __________________ "The gods too are fond of a joke." "If I had only known, I would have been a locksmith. "

August 13th, 2006, 06:46 PM	#18
OTreborO Enthusiast Join Date: Apr 2006 Posts: 638 iTrader: 0 reviews	latest on wiring Relay is under seat because pink wire from fuel pump goes to this relay: Here is what I found with relay unplugged: Pink wire going to fuel pump has 5 V, weird??? Orange Blue has 12V Tan/Green has 6V Red/black has 3V I got a new relay, but it still doesn't work The relay I got has 5 terminals, the original has 4, Autozone guy said that was ok...... Any help appreciated __________________ "Those who forget the past are condemned to repeat it" Rev. Jim Jones

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August 13th, 2006, 09:56 PM	#19
stang fanatic Enthusiast Join Date: May 2006 Location: El Paso, Tx Posts: 861 iTrader: 0 reviews	okay...go back to inertia switch, wire going in is red...has 12v? it should with key on. your red/blk at inertia switch, should have 12v with key on. if not...switch is bad. if you do, and you only have the 3v at the relay...trace the wiring back to inertia switch...wire either shorting or more than likely, a connector behind one of the kickpanels is coroded. __________________ "The gods too are fond of a joke." "If I had only known, I would have been a locksmith. "

August 13th, 2006, 10:26 PM	#20
OTreborO Enthusiast Join Date: Apr 2006 Posts: 638 iTrader: 0 reviews	inertia switch Inertia switch is ok, ohms less than 5 6V at the inerta switch :-( __________________ "Those who forget the past are condemned to repeat it" Rev. Jim Jones

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