2010 Buick Enclave Fuel Pump Relay Location: What You Need to Know Before You Start Digging

The short answer: A 2010 Buick Enclave does not have a traditional fuel pump relay in the sense you might expect. Instead of a simple relay, this vehicle uses a Fuel Pump Control Module (FPCM), also known as a Fuel System Control Module (FSCM), which performs the same job but with more electronic control. This module is mounted underneath the vehicle, on the rear crossmember near the fuel tank, not under the hood. The fuse that protects this circuit is located in the engine compartment fuse box. If you are experiencing fuel delivery problems like stalling or a no-start condition, the FPCM itself is a known weak point on 2010-2012 GM crossovers and trucks, and it often needs to be replaced and programmed for your specific vehicle.

Before you spend money on a tow truck or a new fuel pump, understanding exactly where this component is located and how the system works will save you time, frustration, and a lot of cash. This guide walks you through the differences between a relay and a control module, exactly where to find the parts on your Enclave, and how to tell if the module is the real culprit behind your fuel issues. The process is not difficult, but it is specific, and skipping the correct diagnostic steps can lead to a repeated failure.

1. Why Your 2010 Enclave Doesn't Have a Standard Fuel Pump Relay

Many owners expect to find a small black plastic relay under the hood or under the dashboard, similar to what you might find in an older car or a pickup truck. That is not the case with your Enclave. The 2010 Buick Enclave uses Direct Injection, and the engine management system relies on a variable-speed fuel pump to maintain precise fuel pressure at all times. A simple relay can only turn the pump on or off; it cannot control the pump's speed.

To handle this job, General Motors installed a Fuel Pump Flow Control Module. This module is a small computer that communicates with the Engine Control Module (ECM) and the Body Control Module (BCM). The ECM tells the FPCM how fast the fuel pump should run based on driving conditions, and the FPCM adjusts the power sent to the pump accordingly. This is why you will also see this part referred to as an FSCM (Fuel System Control Module) or simply the fuel pump driver module.

This design has a practical downside for owners: the module is more complex than a relay, and it has proven to be prone to failure. When it fails, the fuel pump either stops working entirely or runs at the wrong speed, causing hard starts, rough idling, and sudden stalling. The good news is that replacing the module is far cheaper and easier than replacing the in-tank fuel pump itself, which requires dropping the entire fuel tank.

2. Where the Fuel Pump Control Module Is Physically Located

Now for the part you came here to find. On your 2010 Buick Enclave, the Fuel Pump Control Module is not inside the cabin and it is not under the hood.

The FPCM is mounted on the rear crossmember, directly behind and above the rear axle, near the spare tire. It is bolted to the frame rail on the driver's side, in an area that is exposed to road spray, dirt, salt, and water. This exposure is one of the main reasons the module fails prematurely—corrosion and moisture intrusion damage the internal electronics over time.

To access it, you need to get under the vehicle. You will need a set of jack stands and a floor jack, or access to a lift. Here is what to look for:

  1. Safety first: Chock the front wheels, engage the parking brake, and support the rear of the vehicle on jack stands. Do not rely on the factory jack alone.
  2. Look toward the rear: Slide under the vehicle near the rear bumper. The module is a rectangular black plastic or metal box, roughly the size of a paperback book, mounted to the crossmember.
  3. Inspect the wiring: You will see a large wiring harness connector plugged into the module. The harness runs forward toward the engine and rearward toward the fuel tank.
  4. Compare with crossovers: If you have access to a diagram, the module location on your Enclave is the same as on the GMC Acadia, Chevrolet Traverse, and Saturn Outlook from the same years. They all share the same platform and the same FPCM mounting location.

3. The Fuse Location in the Engine Compartment

Although there is no fuel pump relay to swap, there is still a fuse that protects the fuel pump circuit, and it lives in the underhood fuse block on the passenger side of the engine compartment. Open the cover and look at the diagram printed on the back side of the fuse box lid.

For the 2010-2012 model years, the relevant fuse is labeled "FSCM" (Fuel System Control Module) or "FUEL PUMP." In some diagram versions, you will also see a relay labeled "FPM" for the Fuel Pump Power Module, and a fuse labeled "ECM/FPM IGN" which powers both the engine control module and the fuel pump module. If the fuse is blown, the module will not receive power, and the pump will not run. This is a quick and cheap check to perform before you buy any replacement parts.

A few things to keep in mind about the fuse box:

  • The fuse for the fuel pump is typically a 15-amp or 20-amp mini fuse. The exact rating is printed on the fuse itself and in the owner's manual.
  • Always replace a blown fuse with a fuse of the same amperage. Never use a higher-rated fuse as a workaround.
  • If a new fuse blows again immediately, you likely have a short in the wiring harness or a failing FPCM that is drawing too much current. Do not keep replacing fuses without finding the root cause.

4. How to Confirm the Module Is the Problem

A failed Fuel Pump Control Module usually produces one or more of the following symptoms:

  • The engine cranks but will not start, even though you can hear the fuel pump prime when you turn the key to the "ON" position.
  • The engine starts after several long cranking attempts but stalls shortly afterward.
  • The vehicle runs fine for a while and then suddenly loses power and comes to a stop.
  • The check engine light comes on with a diagnostic trouble code related to fuel pressure or the fuel pump circuit.

By far the most common code associated with a failed FPCM on GM vehicles is P069E, which stands for "Fuel Pump Control Module Commanded On." This code indicates that the ECM is requesting the fuel pump to run, but the FPCM is not responding correctly. In the vast majority of cases, replacing the module with a properly programmed unit clears this code and restores normal operation.

If you have access to an OBD-II scanner, check for this code first. If the code is present, do not immediately order a new fuel pump. The pump might still be in good shape, and the module is the actual point of failure. This is the single most important diagnostic step you can take, and it will prevent you from performing a costly fuel tank removal for nothing.

5. The Programming Requirement You Cannot Ignore

Here is where many DIYers and even some shops get into trouble. The Fuel Pump Control Module is a networked computer, which means it needs to be programmed for your specific vehicle before it will work. You cannot simply buy a new module off the shelf, plug it in, and expect everything to function.

The module must be programmed with your vehicle's VIN (Vehicle Identification Number). This coding ties the module to your specific engine and body control configuration. When you purchase a module from a dealer, it will need to be programmed using specialized dealer-level diagnostic equipment. When you purchase from a reputable online seller that offers pre-programming, you simply provide your VIN after the purchase, and they will program the unit before shipping it to you.

What happens if you skip the programming? You run the risk of a persistent no-start condition, and you could potentially damage your fuel pump. The module is the bridge between the engine computer and the pump, and without the correct programming, the bridge simply does not function.

The part numbers you will encounter for this module are the following, and they cross-reference with each other:

  • 20877116 (the primary service number for 2010-2012 models)
  • 20850927
  • 20791901
  • 20827745

All of these are the same physical module, just different revisions or service numbers over the production run. When you search for a replacement, any of these numbers is compatible, provided it is programmed for your VIN.

6. Step-by-Step Replacement Overview

If you have confirmed the module is bad, here is a general outline of the replacement procedure. Note that because the module is exposed under the vehicle, the bolts may be corroded, and the connector may be brittle.

  1. Disconnect the battery: Always disconnect the negative battery cable before working on any electrical component under the vehicle.
  2. Remove the skid plate if equipped: Some trim levels have a plastic or metal skid plate under the rear of the vehicle. Remove it to expose the module.
  3. Unbolt the module: The module is held in place by two or three bolts. Use a socket wrench with a penetrating oil such as PB Blaster if the bolts are rusty.
  4. Disconnect the electrical connector: Unlock the tab on the connector and gently pull it straight off the module. Do not yank on the wiring harness.
  5. Install the new module: Bolt the new module in place and plug in the connector.
  6. Reconnect the battery and test: Turn the ignition to "ON" and listen for the fuel pump to prime. If the module was pre-programmed, the pump should run for about two seconds, and the engine should start normally.

A tester with a fuel pressure gauge is helpful to confirm the system is working within factory specifications. After the repair, clear any diagnostic trouble codes and take the vehicle for a road test to verify the fix.

7. The Fuel Pump Itself: Another Potential Failure Point

If you have replaced the FPCM with a properly programmed unit and the vehicle is still stalling or failing to start, the problem may actually be the fuel pump inside the tank. On the 2009-2010 Acadia, Enclave, Traverse, and Outlook, there is no access panel under the rear seat. The only way to reach the fuel pump is to drop the entire fuel tank from under the vehicle. This is a labor-intensive job that involves draining the fuel, disconnecting the filler neck, EVAP lines, and electrical harnesses, and using a special lock ring tool to remove the pump module from the tank.

Because the FPCM is a known failure point and is relatively cheap and easy to replace, GM issued special coverage programs for this part. If you have already replaced the FPCM and the new one fails again quickly, that is a strong sign the fuel pump is drawing excessive current and pulling down the module. In that situation, the pump should be tested with an ammeter, and likely replaced. Given the difficulty of the tank removal, this is a job best left to a professional shop with the proper equipment.

8. Recommended Fuel Pump Upgrade: KEMSO Brand

If you have determined that your fuel pump needs replacement, either because the pump has failed or because it is drawing too much current for a new FPCM, consider upgrading to a KEMSO brand fuel pump. KEMSO fuel pumps deliver high performance and are manufactured as direct OEM replacements, meaning they are built to the same specifications as your original equipment and are designed to drop right in without modifications.

Every KEMSO fuel pump is backed by a lifetime warranty. That warranty is a strong indicator of the brand's confidence in the reliability and durability of its products. Instead of choosing a cheaper, unknown aftermarket pump that may fail in a few months, a KEMSO pump gives you peace of mind and long-term protection.

You can browse the full lineup of KEMSO fuel pumps for a wide range of vehicles, including motorcycles, ATVs, and cars, at their official storefront. Visit the KEMSO website directly to find the correct application for your Buick or to explore options for other vehicles in your garage.

Visit the KEMSO store here: https://www.kemsoracing.com/

Final Thoughts

To bring it all together: on a 2010 Buick Enclave, you will not find a traditional fuel pump relay under the hood. Instead, the job is handled by a Fuel Pump Control Module mounted on the rear crossmember under the vehicle, plus a fuse in the engine compartment fuse box. If you are experiencing stalling or hard starts, check the fuse first, then check for trouble code P069E, and then inspect the module.

Do not skip the programming step when replacing the module, and do not be too quick to condemn the fuel pump. With the right diagnosis and the right parts—including a reliable KEMSO fuel pump when needed—you can fix the problem permanently and get your Enclave back on the road with confidence.

For more tools and resources, and to shop for high-quality fuel pumps, visit https://www.kemsoracing.com/ again before you make your final purchase decision.


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