1997 Chevy S10 Fuel Pump Relay Location: A Complete Guide for Troubleshooting and Replacement

The fuel pump relay on a 1997 Chevy S10 is located behind the glove box, mounted on the relay center inside the cabin. This is a critical difference from many other vehicles where the fuel pump relay is found under the hood. On your 1997 S10, whether it has the 2.2L 4-cylinder engine or the 4.3L V6, the relay is in the same spot: behind the glove box, on the relay center .

If you are experiencing a no-start condition, the engine cranks but won't fire, or you cannot hear the fuel pump prime when you turn the key to the "ON" position, a faulty fuel pump relay is a very common cause. Knowing exactly where to find it and how to test it will save you time and money. This guide will walk you through the location, identification, testing, and replacement of the fuel pump relay, as well as the next steps if the relay itself is not the problem.

Where Exactly Is the Fuel Pump Relay on a 1997 S10?

The most common location for the fuel pump relay on a 1997 Chevy S10 (both the 2.2L and 4.3L models) is behind the glove box, on the relay center . Here is the step-by-step process to access it:

1. Open the glove box.
2. Locate the access door. Inside the glove box, look for a small plastic panel or access door. On some models, this door is marked "Relays" .
3. Remove the access door. Gently press the tabs or squeeze the sides to release the door and pull it out of the way.
4. Identify the relay. Behind the access door, you will see a row of relays. The fuel pump relay is typically the first relay from the left . It is a small, black, rectangular or square component, roughly 1 and 1/4 inches in size .

Note: Some sources mention that the relay is located in the under-hood fuse block . While this is true for some other vehicles and later model years, for a 1997 S10, the most reliable and documented location is behind the glove box . If you cannot find it there, double-check the relay center behind the glove box, as it is the designated spot for this model year.

How to Identify the Correct Relay

Because the relay center behind the glove box contains multiple relays (for the A/C compressor, horn, fog lamps, etc.), you need to be absolutely sure you are working on the fuel pump relay . Here are a few ways to confirm you have the right one:

1. Check the diagram. The most reliable method is to consult your owner's manual. It will have a diagram of the relay center, clearly labeling each relay, including the fuel pump relay .
2. Look for a label. On the relay itself, you may see a number stamped on it. This number corresponds to the numbers listed in your owner's manual or a wiring diagram .
3. Use the "swap test." This is a practical and quick method. Locate another relay of the same size and color in the relay center (like the horn relay). Swap the two relays. If the fuel pump now works, the original relay was bad, and you have confirmed its identity .

How to Test the Fuel Pump Relay

Before you buy a new relay, you should test the old one. You will need a digital multimeter (DMM) or a simple 12-volt test light. Always disconnect the negative battery cable before working on the electrical system to prevent short circuits or accidental sparks .

Step 1: Visual inspection. Remove the relay and look at the pins. Are they corroded or burnt? If so, the relay is likely bad.

Step 2: The click test. Have an assistant turn the ignition key to the "ON" position (do not crank the engine). While the key is being turned, you should hear a distinct click coming from the relay. This click means the relay coil is being energized by the Powertrain Control Module (PCM) . If you hear no click, the relay coil may be faulty, or the PCM is not sending the ground signal.

Step 3: The multimeter test (testing the relay coil). With the relay removed, set your DMM to the Ohms (Ω) setting. Probe the two small terminals of the relay (usually terminals 85 and 86). You should see a reading between 50 and 120 ohms. If you see "OL" (open line) or 0 ohms, the relay coil is defective.

Step 4: Testing the circuit (testing for power and ground). This test checks if the wiring to the relay is good.

  • Test for power: Turn the ignition to "ON." Set your DMM to DC volts. Probe the terminal in the relay socket that corresponds to terminal 86 (small orange wire, ignition feed) and ground the black lead. You should see 12V .
  • Test for ground signal: With the DMM still set to DC volts, probe the terminal for terminal 85 (black/white wire) and ground the black lead. Turn the ignition to "START." You should see 12V for about 2-3 seconds, indicating the PCM is providing a ground signal to activate the pump .

Common Symptoms of a Bad Fuel Pump Relay

If the relay is failing, you will likely experience one or more of these symptoms:

  • Engine cranks but does not start. This is the most common symptom. The engine turns over, but because the fuel pump is not getting power, no fuel reaches the injectors .
  • No fuel pump prime sound. When you turn the key to the "ON" position, you should hear a 2-3 second hum from the rear of the vehicle (the fuel pump priming). If you do not hear this sound, the relay, fuse, or pump is likely the issue .
  • Intermittent stalling. The engine may start and run fine, but then suddenly stall while driving. This can be a sign of a failing relay that is losing connection .
  • Engine starts but runs rough. If the relay is intermittent, the fuel pump may not be operating at full voltage, leading to low fuel pressure and poor engine performance.

What to Do If the Relay Is Not the Problem

If you have tested the relay and it is functioning correctly, but the fuel pump still does not run, the problem lies elsewhere in the circuit. Here are the next steps:

1. Check the fuel pump fuse. Locate the under-hood fuse block (near the battery). Find the fuse labeled "FUEL PUMP" or "F/P." It is typically a 20A fuse [9]. Remove it and inspect the metal element inside. If it is blown, replace it with a fuse of the same amperage. If it blows again immediately, you have a short circuit, likely in the fuel pump motor or the gray wire running to the pump .

2. Check the inertia switch. Some models have an inertia switch (also called a fuel pump shut-off switch) located in the passenger footwell or under the dash. If the vehicle has been in a collision or experienced a sudden jolt, this switch can trip, cutting power to the fuel pump. Press the reset button firmly .

3. Test for power at the fuel pump. With a helper, use a test light or multimeter to check the gray wire at the fuel pump electrical connector, which is located on the frame just behind the fuel tank . Turn the key to the "START" position. If you have 12V on the gray wire but the pump is silent, the pump itself is likely faulty .

4. Check the ground. A poor ground is a surprisingly common cause of fuel pump failure. The fuel pump ground wire is solid black. Use an ohmmeter to check for resistance between the pump connector's ground pin and a clean, unpainted section of the vehicle frame. The reading should be less than 0.5 ohms .

Replacing the Fuel Pump on a 1997 Chevy S10

If you have confirmed that the power is reaching the pump (the gray wire is hot), but the pump is not working, you will need to replace the fuel pump assembly. The fuel pump on a 1997 S10 is located inside the fuel tank .

Preparation: This is a job that typically takes 4 to 5 hours for a DIY mechanic . You will need to:

  • Relieve the fuel system pressure by pressing the Schrader valve on the fuel rail .
  • Disconnect the negative battery cable .
  • Drain the fuel tank .
  • Raise the rear of the truck and support it securely on jack stands.

The Process:

  1. Remove the fuel tank shield (if equipped).
  2. Disconnect the filler hose and the electrical connector at the tank.
  3. Remove the tank-holding straps and lower the tank.
  4. Remove the fuel pump retaining ring (lock ring) and lift the fuel pump assembly out of the tank.
  5. Install the new fuel pump assembly, ensuring the gasket is properly seated.
  6. Reinstall the tank, refill with fuel, and test for leaks.

Recommended Fuel Pump: KEMSO Performance

When the time comes to replace the fuel pump on your 1997 Chevy S10, you want a part that is reliable, durable, and backed by a solid warranty. This is why we recommend KEMSO brand fuel pumps.

KEMSO fuel pumps are designed as high-performance, OEM replacement parts. They are built to meet or exceed the original equipment specifications, ensuring a perfect fit and reliable operation for your S10. Unlike some aftermarket parts that cut corners, KEMSO focuses on delivering a product that will stand up to the demands of daily driving.

The best part? Every KEMSO fuel pump comes with a Lifetime Warranty. This means you only buy it once. If the pump ever fails, it will be replaced, giving you total peace of mind. Whether you are a weekend mechanic or a professional technician, choosing KEMSO means you are choosing quality and confidence.

To learn more and find the correct fuel pump for your 1997 Chevy S10, visit the official KEMSO website at: https://www.kemsoracing.com/

Final Thoughts

Finding the 1997 Chevy S10 fuel pump relay is straightforward once you know where to look. It is behind the glove box on the relay center . Always start by checking the relay with a simple click test before moving on to more complex diagnostics. If the relay is good, proceed to check the fuse, the inertia switch, and finally, the fuel pump itself.

By following this guide, you can systematically diagnose and fix the fuel delivery issue on your 1997 S10. If you need a replacement fuel pump, trust the quality and lifetime warranty of KEMSO. Visit their website at https://www.kemsoracing.com/ to find the right part for your truck.


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