Honda Fuel Pump Relay Genuine OEM Automatic 39794-SDA-004 Mount

Description

Product Overview

The Honda Genuine OEM Fuel Pump Relay (model 39794‑SDA‑004) is engineered to deliver precise control of the fuel pump circuitry in a wide variety of automotive applications. Constructed with high‑conductivity silver contacts, the relay ensures low resistance pathways for electrical current, reducing heat buildup and extending component lifespan. Its normally‑open (NO) contact configuration means the circuit remains open until the control signal activates, providing a reliable safety margin that prevents unintended fuel pump operation. The relay operates automatically, responding to voltage changes from the engine control unit without requiring manual intervention, which simplifies installation and improves overall vehicle reliability.

Designed for surface‑mount installation, the unit measures just one inch on each side, allowing it to fit into compact engine bays where space is at a premium. The robust housing is molded from a smooth, heat‑resistant polymer that protects internal components from vibration, moisture, and chemical exposure common in automotive environments. Weighing only 0.32 ounces, the relay adds negligible mass to the vehicle while maintaining structural integrity. The part number 39794‑SDA‑004 matches the original equipment manufacturer (OEM) specification, guaranteeing a direct fit and compatibility with Honda‑branded fuel systems as well as many aftermarket setups that reference the same OEM identifier.

Beyond its core electrical functions, the relay incorporates design features that aid technicians during service. The clear labeling on the top surface indicates terminal assignments, making wiring connections straightforward and reducing the chance of errors during replacement. The component has passed rigorous quality testing, including endurance cycles, temperature extremes, and corrosion resistance, to meet Honda’s exacting standards for durability and performance. As a result, owners benefit from consistent fuel delivery, smoother engine start‑up, and reduced risk of fuel‑related faults that can lead to costly repairs.

Technical specifications confirm that the relay meets industry standards for automotive electrical components. The unit’s contact rating is rated for up to 30 A at 12 V, providing ample capacity for most fuel pump circuits. Its operating temperature range spans from –40 °C to +125 °C, ensuring reliable performance in extreme climates, from cold winter mornings to hot summer afternoons. The relay’s low profile of 1 × 1 × 1 inches and weight of only 0.32 oz make it lightweight yet robust, contributing to overall vehicle weight reduction. Compliance with RoHS and REACH regulations guarantees that the component is free from hazardous substances, aligning with modern environmental standards. The part’s ASIN B00AJTMC08 and its best‑seller rank in the automotive replacement fuel pump relays category reflect its popularity among consumers seeking dependable OEM replacements.

Reliability testing for the relay includes accelerated life cycles that simulate thousands of on‑off events, confirming that the contacts maintain their conductivity over the vehicle’s expected service life. Temperature cycling tests expose the unit to rapid shifts between extreme cold and heat, verifying that the internal components do not crack or degrade. Vibration testing replicates the harsh conditions of road travel, ensuring that the mounting points and solder joints remain secure. These rigorous assessments are documented in Honda’s quality assurance reports, which are available upon request for fleet operators and service centers that require detailed compliance records. The result is a component that not only meets but often exceeds the durability expectations of modern automotive fuel systems.

Usage

This relay is ideal for use in gasoline‑powered passenger cars, light trucks, and crossover SUVs that rely on an electric fuel pump to maintain proper fuel pressure. It is commonly installed in the fuel pump control module, where it receives a low‑voltage signal from the engine control unit (ECU) and switches the high‑current circuit that powers the pump. The automatic operation mode ensures the pump engages only when the ECU commands fuel flow, such as during engine start, acceleration, or cruise conditions, thereby protecting the pump from unnecessary wear.

Mechanics and DIY enthusiasts will find the surface‑mount design simplifies the replacement process. The relay can be accessed by removing a few fasteners and disconnecting the wiring harness, after which the old unit slides out and the new one slides in without the need for drilling or extensive rewiring. Because the relay’s dimensions are standardized, it fits into existing mounting brackets and aligns with pre‑drilled holes, minimizing installation time and labor costs.

In addition to original Honda vehicles, the part is frequently used in compatible models from other manufacturers that share the same fuel pump relay specifications. This makes it a versatile spare part for repair shops that service a broad range of makes and models. The reliable performance of the silver contacts also makes the relay suitable for high‑performance applications where consistent fuel pressure is critical, such as in tuned engines or vehicles equipped with aftermarket fuel delivery upgrades.

During installation, it is advisable to verify the voltage at the relay’s coil terminals before removal to confirm that the control circuit is receiving the correct signal from the ECU. After the old relay is removed, inspect the socket for any signs of corrosion or debris, and clean it with an appropriate electrical contact cleaner if necessary. Re‑install the new relay ensuring that the orientation matches the original, as the coil and contact sides are not interchangeable. Tighten the mounting screws to the manufacturer‑specified torque, typically around 5 Nm, to prevent loosening due to engine vibration. Once the relay is secured, reconnect the battery and perform a functional test by turning the ignition on and listening for the fuel pump’s audible click, indicating that the relay is energizing correctly. Finally, clear any stored fault codes using a scan tool to reset the system and confirm that the repair has resolved the issue.

Regular maintenance of the fuel system can further extend the lifespan of the relay. Periodically checking the fuel pump voltage and ensuring the relay’s terminals are free of corrosion helps maintain optimal electrical flow. If the vehicle experiences intermittent stalling, a quick inspection of the relay’s contacts with a contact cleaner can restore performance without full replacement. Additionally, updating the vehicle’s ECU software may improve the relay’s control logic, as newer firmware versions often include refined fuel management algorithms that reduce stress on the relay during transient conditions.

Why Choose Us

Choosing the genuine Honda fuel pump relay means you are receiving a component that matches the exact engineering tolerances of the original part installed at the factory. Our inventory is sourced directly from Honda’s authorized manufacturing facilities, ensuring that each relay carries the authentic part number 39794‑SDA‑004 and the OEM branding that guarantees fit and function. This eliminates the risk of counterfeit or sub‑standard alternatives that can cause premature failure or erratic fuel system behavior.

We stand behind every relay with a comprehensive warranty that covers defects in materials and workmanship for a period of twelve months from the date of purchase. Our dedicated technical support team is available to assist with installation guidance, troubleshooting, and compatibility questions, providing you with confidence throughout the product lifecycle. In addition, each unit undergoes a final inspection that includes electrical continuity testing, contact resistance measurement, and visual inspection for any manufacturing anomalies.

Our commitment to quality extends to the packaging and shipping process. The relay is packaged in anti‑static protective material and placed within a sturdy box that safeguards it against physical damage during transit. We also provide detailed documentation, including a wiring diagram and installation instructions, to help you integrate the relay into your vehicle’s fuel system quickly and correctly.

Our supply chain management ensures that each relay is stocked in climate‑controlled warehouses, preserving the integrity of the silver contacts and polymer housing until the moment of shipment. We work closely with Honda’s manufacturing partners to receive regular updates on part revisions, allowing us to offer the latest version of the relay as soon as it becomes available. In addition, we are committed to sustainable business practices; packaging materials are recyclable, and we strive to minimize carbon emissions by optimizing shipping routes and consolidating orders. Customers who purchase through our authorized channel also gain access to exclusive technical bulletins and service manuals that provide deeper insight into the relay’s role within the vehicle’s fuel management system, empowering them to perform more informed maintenance and troubleshooting.

Key Features

• Silver contacts provide low resistance for efficient power transfer and reduced heat.
• Automatic operation eliminates the need for manual switching, enhancing convenience.
• Compact surface‑mount design fits tight engine bays and simplifies installation.
• Durable polymer housing resists vibration, moisture, and chemical exposure.
• Comes with a full warranty and dedicated after‑sales support for peace of mind.

FAQ

What vehicles are compatible with the 39794‑SDA‑004 relay?

The 39794‑SDA‑004 relay is listed as a genuine Honda part and fits any Honda model that originally used this part number. Common applications include the Civic, Accord, CR‑V, and Fit across model years from the early 2000s through the present, as well as certain Honda‑derived platforms such as the Acura RSX and the older Honda Odyssey. In addition, many non‑Honda vehicles share the same relay specifications, especially those that employ a three‑terminal, normally‑open fuel pump control circuit. When selecting a replacement, verify the vehicle’s service manual or the existing relay’s part number to ensure a direct match. If the vehicle’s wiring harness and connector type are compatible, the relay can be installed without modifications, providing a seamless OEM‑level replacement. Because the relay conforms to Honda’s OEM specifications, it also works with aftermarket fuel pump modules that require the same electrical characteristics, making it a versatile spare for both factory and custom installations. When in doubt, consult a qualified mechanic to verify compatibility before ordering.

How do I know if the relay is faulty?

Symptoms of a failing fuel pump relay typically appear as intermittent engine stalling, difficulty starting, or a complete loss of fuel pump operation. The engine may crank longer than usual before starting, or it may shut off shortly after ignition if the relay is not delivering power consistently. In many cases, a diagnostic scan will reveal error codes such as P0234 or P0235, which indicate a problem with the fuel pump circuit. To confirm the relay’s condition, you can perform a simple continuity test with a multimeter: remove the relay, set the meter to the resistance (ohms) setting, and measure between the control terminals. A healthy relay will show a low resistance value (typically under 100 Ω) when the coil is energized and an open circuit when de‑energized. If the measured resistance is excessively high or the contacts do not open and close as expected, the relay should be replaced. If the relay tests within specifications but the problem persists, inspect the fuel pump and wiring for secondary faults.

Can I replace the relay yourself?

Yes, the surface‑mount Honda fuel pump relay is designed for straightforward replacement by qualified DIYers or professional technicians. Before beginning, disconnect the vehicle’s battery to prevent any accidental short circuits. Locate the relay in the fuel pump control module, which is typically mounted near the fuel tank or within the engine compartment. Remove any securing screws or clips, then unplug the wiring harness from the relay’s terminals. The relay’s compact size allows it to be lifted out of its socket without the need for additional tools. Align the new unit with the mounting holes, re‑attach the fasteners, and reconnect the harness, ensuring each terminal matches the original labeling. Tighten the mounting screws to the manufacturer‑specified torque, typically around 5 Nm, to prevent loosening due to engine vibration. Once the relay is secured, reconnect the battery and perform a functional test by turning the ignition on and listening for the fuel pump’s audible click, indicating that the relay is energizing correctly. Finally, clear any stored fault codes using a scan tool to reset the system and confirm that the repair has resolved the issue. Always consult the vehicle’s service manual for specific torque values and safety precautions. Always wear safety glasses and follow the vehicle’s grounding procedures to avoid accidental short circuits.

What warranty coverage does the relay have?

The relay is covered by a twelve‑month limited warranty that protects against any defects in materials or workmanship. If the part fails within the warranty period under normal operating conditions, we will provide a replacement at no additional cost. To initiate a warranty claim, contact our customer support team with the original purchase receipt, the part number, and a description of the issue. Our technicians may request photos of the installed relay or a diagnostic report to verify the failure mode. Once the claim is approved, we will ship a new relay to the address on file and include instructions for return shipping of the defective unit. The warranty does not cover damage caused by improper installation, exposure to extreme environmental conditions, or modifications to the vehicle’s electrical system that are not recommended by the manufacturer. The warranty also covers shipping costs for the replacement unit, ensuring a hassle‑free experience.