Cars & Trucks Logo

Related Topics:

Ignacio Becerra Posted on Feb 02, 2013

No power to fuel pump.

Have power to fuel pump relay but no power at the inertia switch. HELP!!!

1 Answer

Anonymous

Level 1:

An expert who has achieved level 1.

New Friend:

An expert that has 1 follower.

Corporal:

An expert that hasĀ over 10 points.

Problem Solver:

An expert who has answered 5 questions.

  • Contributor 8 Answers
  • Posted on Feb 02, 2013
Anonymous
Contributor
Level 1:

An expert who has achieved level 1.

New Friend:

An expert that has 1 follower.

Corporal:

An expert that hasĀ over 10 points.

Problem Solver:

An expert who has answered 5 questions.

Joined: Feb 02, 2013
Answers
8
Questions
0
Helped
889
Points
34

What kind of car/truck is it? Is the inertia switch in trunk?

If you have power before relay but none after the relay is bad.

The inertia switch can also get tripped by very hard bumps jolts etc and has to get reset if it does.

  • 1 more comment 
  • Ignacio Becerra Feb 02, 2013

    swapped out relay and made sure inertia switch was not tripped, still nothing

  • Anonymous Feb 02, 2013

    so you've checked for power before and after relay and inertia switch. Have you checked for power at the fuel pump (actual plug) or can you access it?

  • Anonymous Feb 02, 2013

    or are you just going by whether or not the fuel pump runs?

×

2 Related Answers

Anonymous

  • 1861 Answers
  • Posted on Jul 17, 2009

SOURCE: I have a 99 tacoma with no power to fuel

Look to see if you have power at pin 1 of the circuit opening relay. The C.O. Relay is what powers the fuel pump. If you have power there (a blue wire), you have an open circuit between the relay and the pump.

Ad
emissionwiz

Marvin

  • 85242 Answers
  • Posted on Sep 02, 2009

SOURCE: where is the fuel pump relay on 1991 lincoln

the fuel pump is inside the gas tank, this is true on all Fords with electronic fuel injection

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

0helpful
1answer

Where fuel box for fuel pump

? If you mean the Power Relay box, they are usually under the hood and there is a fuel pump relay. If you mean the "Inertia switch" which disconnects fuel pump power, it can be either behind the front kickpanels or behind a cover panel in the rear cargo area. If you have Air-ride, they like to put the Inertia switch close to it. There is a reset button on the Inertia switch.
1helpful
1answer

1989 f-250 inertia fuel shut-off switch switch location

This should be in the owner's manual. I found the below on autozone.com, their repair help location:
An inertia switch is used as a safety device in the fuel system. The inertia switch is located in the cab, generally under the dashboard on the right side. It is designed to open the fuel pump power circuit in the event of a collision. The switch is reset by pushing each of 2 buttons on the switch simultaneously (some models use switches with only one reset button). The inertia switch should not be reset until the fuel system has been inspected for damage or leaks.
When the ignition switch is ON , it turns the EEC power relay ON . The EEC power relay provides power to the powertrain control module (PCM) and the control side of the fuel pump relay. Power for the fuel pump(s) is supplied through a fuse link or high current fuse attached to the starter solenoid (battery side). From the fuse link or high current fuse, current flows through the fuel pump relay and inertia switch to the fuel pump(s). The fuel pump relay is controlled by the PCM.
When the ignition switch is turned ON , the fuel pump(s) will operate. If the ignition switch is not turned to the START position the PCM will shut the fuel pump(s) OFF after 1 second. The PCM will operate the fuel pump(s) operate the fuel pump(s) when the ignition switch is turn to START position to provide fuel while cranking.
After the engine starts, the PCM will continue to operate the fuel pump(s) unless the engine stops, drops below 120 rpm or the inertia switch is tripped.
0helpful
1answer

I have a 1996 mustang v6 no power to fuel pump. Bought used fuel pump relay still have np power. Safty switch is good. Unpluged fuel turned switch on and i have constant power of 9.52 volts plug in pump...

9.5 volts sounds like the power coming from the gas gauge.
I am showing a relay module with the fuel pump and pcm relays built in along with two other relays. The fuel pump relay should not be accessable. In most cases the pump relay gets power from a 20amp fuse and the computer grounds the relay when needed. Power goes from the pump relay to the inertia switch then to the pump. So the inertia switch should be hot when the pump relay is activated.
8helpful
1answer

Car will turn over but won't start. Through the

No noise from fuel pump when you turn over the car .First thing get voltage at fuel pump relay checked, is there 12 volt to the relay.If no, then problem is again the relay.--------- To reconfirm the problem, try other test, that is remove the relay and by pass the relay terminals with a jumper wire .Then with 12 volt external battery give power to fuel pump connector and see, if the fuel pump starts, then its clear that fuel pump relay is faulty.----------- Also other problem can be fuel pump inertia switch.If the inertia switch is faulty then also fuel pump will not start.-------- The fuel pump relay on a 1995 Ford Explorer is in the power distribution
box, in the engine compartment, driver's side near the firewall.----------
The fuel pump inertia switch is in the right front passenger area
it is below the dash but above the carpet in the right hand corner.--------
Its a push button type inertia switch.
--------
Fuel Pump Activation
When ignition switch is turned to START position, PCM operates fuel pump relay to provide fuel for starting engine. PCM senses engine speed and shuts off fuel pump by opening ground circuit to fuel pump relay when engine stops or engine speed drops to less than 120 RPM. When ignition switch is in ON position, EEC power relay is energized (contacts closed). Power is provided to fuel pump relay and timer in PCM. Fuel pump receives power through fuel pump relay contacts.
Inertia Fuel Shutoff (IFS) Switch
All models use an electrical interrupt switch in fuel system. During a collision or vehicle rollover, electrical contacts within inertia switch open, shutting off fuel supply to electric fuel pump. Fuel supply is interrupted even when engine is running.
A reset button is located on switch assembly. If electrical circuit trips, vehicle will not restart until switch is reset. Fuel system should be inspected before resetting switch.
IFS switch is located under instrument panel, near right side of transmission hump.
----------- If the fuel pump relay, the inertia switch and fuel pump all checked ok, and fuel pump is working with direct 12 volt source to fuel pump.Then problem relates to computer.The computer (power control module, PCM) is faulty and has to be replaced.--------- This will help.Thanks.Helpmech.
1helpful
1answer

Starter motor went out on 92 5.0 ho replaced it and new battery, now fuel pump does not work I get a 542 code checked fuel pump relay and inertia switch both good fuse good

  • Code 542 indicates one of the following conditions:

Engine Starts:

· Fuel Pump secondary circuit shorted to power

· Fuel pump relay contacts always closed

· Open in fuel pump monitor (FPM) circuit between ECU and connection to POWER TO PUMP circuit

· Heated Exhaust Gas Oxygen (HEGO) sensor shorted to power

· faulty ECU

Engine Does Not Start:

· Open inertia switch or inertia switch circuit

· Open in or between ECU and fuel pump (This includes open in fuel pump brushes/windings)

· faulty ground connection at fuel pump

The easiest way to check this circuit is to go to the fuel pump relay. If the relay clicks when the key is turned to the "RUN" position, then the inertia switch circuit is ok.

The Pink/Black wire starts from the fuel pump relay and goes two directions. One side goes back to the fuel pump. The other side is the fuel pump monitor circuit and goes to pin #8 at the ECU. This wire should only be hot for a second or two when the ignition is turned to the RUN position.

The fuel pump relay receives power on the Black/yellow wire. It comes from a fusible link at the power distribution center. This wire should be hot at all times.

If all the above is working as designed, them you probably have a bad fuel pump.

0helpful
2answers

No fuel to the rail. New pump,filter,control module over radiator(2).checked inertia switch. if wire to inertia switch is same color code as wire leaving ECM then no power leaves ECM when switch is...

It helps if you tell what year,model, engine you are working on. Is power at the Inertia Switch? The power comes from the FUEL PUMP RELAY, the ECM only grounds the relay to turn it on. but not knowing what you are working on, thats all the info I have .
1helpful
1answer

Where is the fuel relay

There is a fuse for the fuel on the firewall inside the cab:



391a198.gif
Fuel Pump The fuel delivery system uses either a high or low-pressure in-line or in-tank electric fuel pump, with some models equipped with both. It is a recirculating system that delivers fuel to a pressure regulating valve in the throttle body and returns excess fuel from the throttle body regulator back to the fuel tank. The electrical system uses two types of control relays, one controlled by a vacuum switch and the other controlled by the powertrain control module (PCM) to provide power to the fuel pump under various operating conditions.

An inertia switch is used as a safety device in the fuel system. The inertia switch is located in the cab, generally under the dashboard on the right side. It is designed to open the fuel pump power circuit in the event of a collision. The switch is reset by pushing each of 2 buttons on the switch simultaneously (some models use switches with only one reset button). The inertia switch should not be reset until the fuel system has been inspected for damage or leaks.
When the ignition switch is ON, it turns the EEC power relay ON. The EEC power relay provides power to the powertrain control module (PCM) and the control side of the fuel pump relay. Power for the fuel pump(s) is supplied through a fuse link or high current fuse attached to the starter solenoid (battery side). From the fuse link or high current fuse, current flows through the fuel pump relay and inertia switch to the fuel pump(s). The fuel pump relay is controlled by the PCM.
When the ignition switch is turned ON, the fuel pump(s) will operate. If the ignition switch is not turned to the START position the PCM will shut the fuel pump(s) OFF after 1 second. The PCM will operate the fuel pump(s) operate the fuel pump(s) when the ignition switch is turn to START position to provide fuel while cranking.
After the engine starts, the PCM will continue to operate the fuel pump(s) unless the engine stops, drops below 120 rpm or the inertia switch is tripped.
12helpful
2answers

1997 Ford F150 Electric Fuel Pump will npt pump

Did you check the fuel inertia switch in the passenger side kick panel ?

The fuel pump is powered :
the fuse to the fuel pump relay.
The fuel pump relay to the fuel inertia switch
The fuel inertia switch to the fuel pump itself.

At the fuel inertia switch in the kick panel, power from the relay is the Dark Green w/ Yellow stripe wire and the pink w/ black stripe wire is the power. from the fuel inertia switch to the fuel pump.

If you jumper the fuel pump relay, you should hear it run. If not pull the fuel pump relay, and check the pins in the relay socket, pin 30 should be the power from the fuse.

50b0c31.jpg

If you have power at pin #30, jumper the relay socket as shown with the red line above, and check the dark green w/ yellow stripe wire at the fuel inertia switch for power.
Press the button on the top of the fuel inertia switch, and check for power leaving the fuel inertia switch on the pink w/ black stripe wire.

This is tests good, check for power at the fuel pump, same pink w/ black stripe wire.
Fuel inertia switch info is in the owners manual, If you did not get an owners manual with your truck ( purchased used ), you can download one from Ford :
https://www.fleet.ford.com/maintenance/owners_manuals/default.asp
2helpful
1answer

No power at ineartia switch

try running power from relay to the inertia switch through a jumper wire and see if pump works. you might have a pinched or broken wire in the factory harness.
4helpful
3answers

My fuel pump is not getting power, I've changed the relay but still not getting power to the fuse or the pump

The fuel relay and inertia switch could be two different items. The inertia switch kills power to the pump. If there is a relay in between the inertia switch and the pump, then it would mean the inertia switch was tripped by slamming a door or an impact. Check your owners manual for the inertia switch. This website advertises online service manual reference.
Not finding what you are looking for?

104 views

Ask a Question

Usually answered in minutes!

Top Cars & Trucks Experts

ZJ Limited
ZJ Limited

Level 3 Expert

17989 Answers

john h

Level 3 Expert

29494 Answers

Arnie Burke
Arnie Burke

Level 3 Expert

7339 Answers

Are you a Car and Truck Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...