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No power to fuel pump, fuses are good

Hi guys. I have samsung sm3 2005 model. After i start my car everything was fine for only a minute and suddenly the engine stop. I realize that no power to the fuel pump andguys. I have samsung sm3 2005 model. After i start my car everything was fine for only a minute and suddenly the engine stopped. I realize that no power to the fuel pump where the pump is working fine when i connect it to the battarey. But when install the pump to its place at the filter doesnt work. I checked all the fuses are fine and i think the crank sensor is good as i notice the move of the RPM indicator. What is the issue think guys and thanks in advance

You made me go to Mr. Google as I had no idea what a Samsung SM3 was . Turns out it is a Korean made Renault . Renault has not been sold here in the United States for years.

Yes. Still a car with 4 wheels

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Correct, but do 2005 Renault’s use an “Inertia Switch” or a “Fuel pump Relay”

Oh Sweet Lord Jeez…ahem… I’m liteally sitting here shuddering at the thought of there existing a Korean made Renault? Holy BeJeez…

Anyhow… OK… lets say this veehicle conforms to what has become commonplace in cars of today. @It_s_Me already addressed the question of …Does the car have an Inertia Switch and or FPR Fuel Pump Relay.

My money is on it having at least the Fuel Pump Relay…it may have some additional crash protection for this circuit that cuts power in the event of a roll over or crash…dont overlook this…very good point to have made find out what kind of crash protection this circuit has if any…and look into resetting it…if possible.

Here is a quick test to perform… its called the KOEO test… Key On Engine Off… Get in the car…doors closed…windows up. Turn your key all the way on but do not start the engine…and listen carefully inside the car…do it again…listen. You should hear the fuel pump prime for 2 seconds or so and stop. Let us know the results of this test… Can you hear the fuel pump run for a few secs?

Back to the FPR… Find it… Pull it out… look in the fuse box for identical relays and swap it… very common to share relays across different circuits… For instance you may find your horn uses the same exact relay as the fuel pump… Pull the original relay…and swap with another

See whatchagets and report back

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Does a tachometer in a Renault gets its signal from the crank sensor? Legit question, as I have zero idea

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It has a relay no Inertia Switch

Yes as the RPM indicator move when turn the key. The crank sensor is fine

Careful use of a circuit diagram can help narrow down the possibilities.

On some cars, low oil pressure turns off the fuel pump once the engine is running. A faulty oil pressure sending unit, or its wiring, can also turn off the fuel pump.

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Thanks for the new info. Dont think the issue is related to the oil pressure as the car is old model. 2005

The pressure may in fact be OK, but the sender could be bad. Do you have an oil pressure light? Does it come on when you turn the key to Run (not all the way to Start)? Does it turn off once the engine starts?

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I’m sorry but I shudder with fear when someone mentions a fuel pump issue. I have spent thousands and many hours dealing with fuel pumps. Sometimes the pump, sometimes the wire harness, sometimes the connector didn’t make contact. I have swapped computers, pump relays, even ran new wires from the pump to the computer in desperation. Toward the end, the longest I got from a pump was one year, and the shortest was two blocks from the shop. Yes and more than one shop and towing from a 50 mile radius except once at 200 miles. So now you ad in a Korean-French vehicle instead of a US GM, and I would run for the hills and take whatever I could get from the scrap yard. I will never chase a fuel pump problem again. I will trade cars.

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Thanks for replying. My car has no Inertia Switch but has fuel pump fuse which is in good condition. I thought the issue is related to the crank sensor but i informed that once the RPM indicator is moving when start the key, that means the sensore is good. I didnt chech the relay (the small black box)

Thank you guys. Finally i found the issue place. It is a connector indide fuel filter


Yep… That’d do it… That happens when the connectors inside that plastic lose their grip on each other…this forces the electricity into a smaller footprint, which creates heat. Unfortunately these things happen and there is no telling when until this occurs.

Glad you found it, as you would most likely have done while poking around the pertinent areas of an issue like this.

Good work.

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Thank you sir