
Cummins ISX12G Fuel Control Module 2018-2024: OEM 5664261
CUMMINS ISX12G FUEL CONTROL MODULE 2018-2024: OEM 5664261

ORDERS PLACED BEFORE 3PM EST WILL SHIP SAME DAY

WARRANTY
1M MILES OR 1 YEAR
PRODUCT DESCRIPTION
This is a Remanufactured Tamerx Fuel Control Module, Tamerx part number 5664261RM ( OEM Part Number 5664261 ). All parts are proudly remanufactured in the U.S.A. to the highest of OEM standards, and improvements are often applied to the original design in the remanufacturing process. This part is primarily made for a Cummins ISX12G, production years 2018-2024, and comes with a One Million Miles or One Year Warranty. For additional warranty info Click Here
OEM NUMBERS
| Primary OEM | 5664261 |
| Additional OEM | 4399796, 5664261 |
ADDITIONAL DETAILS
| CONDITION | Remanufactured |
| UPC / Barcode | 00840490556898 |
| WEIGHT | 18.00 LBS |
SHIPPING OPTIONS
Ship Weight : 18.00 LBS
UPS Ground, 2nd Day Air, Next Day Air
SHIPPING POLICY
Tamerx Diesel Products ships via UPS Ground. Next day air shipping can be arranged for a reasonable price of anywhere from $50.00 - $100.00 depending on the weight of the product and your location. We will do everything we can to make sure that you get the service you need. We understand how important it is to receive your order as quickly as possible.
In most cases Tamerx Diesel Products only needs one address, as long as your product is shipping to the same location as your billing information. In order to eliminate credit card fraud, your billing information must match the credit card you provide.
The terms, conditions, and details of our warranty vary from product to product. Specific warranty details can be found below.
Tamerx Diesel Products provides a replacement warranty on all of our parts. The duration and mileage limitations of the warranty vary by product and are specified on the product's detail page/item listing.
Please note that the warranty covers replacement of the part and the cost of shipping the replacement part to you only. It does not cover any shop, labor, towing, or any similar or related costs. This is not a "money back guarantee".
If you experience a problem with your part or it is not functioning properly, the correct warranty procedure is to call us at (510) 257-1777 (8:00 AM - 5:00 PM ET Monday through Friday). Be sure to have your order number and/or other relevant order information ready so we can easily locate your order and resolve your issue as quickly as possible. From that point, we will review with you any troubleshooting steps that may need to be taken and other areas or systems that can be checked to rule out external problems contributing to your part's issue. If a replacement is determined to be necessary, we will then arrange for your replacement part to ship out ASAP and issue any necessary return shipping labels and/or documents.
As is the case for the majority of the diesel products sold on Tamerx Diesel Products, your part's warranty is active as soon as you install it. In some other cases, warranty activation is contingent upon you sending us your core (i.e., your old part). Tamerx Diesel Products will provide you a return shipping label for parts that have a warranty with a core return condition. When we have received your core return, the part's warranty coverage begins. We reserve the right to void the product warranty if your core is not received within the allotted time, or if it isn't received at all. If the warranty for the diesel part you are purchasing has a core return requirement, it will be clearly noted on the product detail page/item listing.
What is a Core Charge?
A core charge (also called "core deposit") is similar to the deposit you might pay for a can or bottle of soda and is a standard requirement in the auto parts industry. For example, in many states, to promote recycling, you pay a deposit when you purchase a can of soda and receive your deposit back when you return the empty can. Many automotive parts have a core charge, or core price, that works in essentially the same way as a soda can deposit.
30 Day Core Charge Hold
You authorize Tamerx Diesel Products, to hold your credit card for the specified core charge amount and that you agree to return your core with 30 days of receiving the purchased part. When we have received your core return, the hold is released and the core charge payment is canceled.
The customer, or parts buyer, is responsible for any shipping costs associated with core returns unless otherwise specified in the product listing/detail page. Tamerx Diesel Products offers prepaid UPS shipping labels (SKU numbers UPS-CR1 and UPS-CR2) for use in returning your core that are available for purchase on our website during your shopping/order process.
The shipping label you will need to use for the core return is dependent upon what part you are purchasing. UPS-CR1 is good for cores weighing up to 20 pounds. UPS-CR2 is appropriate for shipping cores weighing 21 pounds or more. You must include enough information with the core return that clearly identifies it as a.) a Core Return, and b.) contains enough information we can use to clearly associate the core return with your order. Including a copy of the invoice or packing slip that came with the original shipment, clearly marked "Core Return", is ideal. Alternately, you can include a note marked as "Core Return" that includes your order number, full name and address, and phone number or other contact information. Failure to include this information with your returned core will most likely delay any due core credit being issued and/or delay any applicable warranty activation. Core returns need to be for the exact part purchased and cannot be damaged. Substituting another part in place of the part you have purchased is not acceptable.
All fluids must be drained.
If you have purchased a set or a parts package, you will need to return cores for all components of the set. For example, if you have purchaed a high pressure oil pump with an IPR valve, you will need to return both HPOP and IPR valve cores to receive proper credit. If you have purchased an EGR cooler/EGR valve package, your core return must consist of an EGR cooler core and an EGR valve core, or core credit will not be given.
Core Charges are often mandated by state legislature, and, as such, the actual core charge and taxes on the charge may vary depending on the state in which you buy your part. The Tamerx Diesel Products core charge presented to you online today with your item is representative of the most common core charge.
Engineered to support precise fuel system management, the Cummins ISX12G Fuel Control Module (2018–2024) OEM 5664261 is a critical component for maintaining reliable engine operation. Manufactured to meet original equipment specifications, it ensures accurate compatibility with Cummins ISX12G natural gas engines across the specified model years. This fuel control module regulates fuel delivery by processing engine data and coordinating communication between key electronic components, helping maintain consistent engine operation and efficient combustion. Constructed from durable, high-quality materials, it is designed to withstand demanding operating conditions and continuous use in heavy-duty applications. Ideal for fleet operators, technicians, and maintenance professionals, this OEM fuel control module helps ensure dependable engine management and long-term reliability.
FITMENT CHART
| YEAR | MAKE | ENGINE(S) | ||||
|---|---|---|---|---|---|---|
| 2018 | Cummins | ISX12G | ||||
| 2019 | Cummins | ISX12G | ||||
| 2020 | Cummins | ISX12G | ||||
| 2021 | Cummins | ISX12G | ||||
| 2022 | Cummins | ISX12G | ||||
| 2023 | Cummins | ISX12G | ||||
| 2024 | Cummins | ISX12G | ||||
PEOPLE ALSO ASKS | BLOG(S)
The Cummins ISX12G Fuel Control Module (OEM 5664261) is a critical electronic engine management component designed for 2018–2024 Cummins ISX12G natural gas engines. Its primary function is to regulate fuel delivery by communicating with the engine's control system and managing how much fuel is supplied under different operating conditions. This helps ensure the engine operates efficiently, responds correctly to changing loads, and maintains proper combustion.
Rather than delivering fuel mechanically, the Fuel Control Module uses electronic controls to monitor and adjust fuel flow based on real-time engine data.
What Does the Cummins 5664261 Fuel Control Module Do?
- Regulates fuel delivery
- The module precisely controls the amount of fuel supplied to the engine based on current operating conditions, helping maintain consistent engine operation.
- Communicates with the Engine Control Module (ECM)
- It works with the ECM to process sensor information and make real-time adjustments to fuel delivery for smooth engine performance.
- Supports efficient combustion
- By supplying the correct amount of fuel at the right time, the module helps the engine achieve clean and stable combustion.
- Responds to changing engine demands
- Whether the engine is idling, accelerating, or operating under heavy load, the module continuously adjusts fuel flow to match current requirements.
- Assists emissions control
- Accurate fuel management helps support the engine's emissions system by promoting cleaner combustion and reducing unnecessary exhaust pollutants.
- Monitors fuel system operation
- The module works with other electronic components to monitor fuel system performance and assist in diagnosing potential issues.
The Cummins ISX12G Fuel Control Module (OEM 5664261) serves as the fuel management center of the engine. By electronically controlling fuel delivery and working closely with the ECM, it helps maintain efficient combustion, reliable engine operation, and proper emissions performance. A properly functioning Fuel Control Module is essential for keeping compatible Cummins ISX12G engines operating smoothly and efficiently.
A failing Fuel Control Module (FCM) should be diagnosed and repaired as soon as possible. The Fuel Control Module helps manage fuel delivery and communicates with other engine control components to ensure proper engine operation. When it begins to fail, you may experience drivability issues, reduced fuel efficiency, or even a no-start condition.
Taking prompt action can help prevent additional damage to the fuel system and minimize downtime.
Here are the steps you should take if your Fuel Control Module is failing:
- Scan for diagnostic trouble codes
- Use a diagnostic scanner to check for fuel system or communication-related fault codes. These codes can help identify whether the issue is with the Fuel Control Module or another component.
- Inspect the wiring and connectors
- Check for loose connections, damaged wiring, corrosion, or moisture intrusion. Electrical problems can often mimic Fuel Control Module failure.
- Verify battery and charging system voltage
- Low battery voltage or charging system issues can affect module operation and cause intermittent faults.
- Inspect the fuel system
- Check the fuel pump, fuel filter, fuel injectors, and fuel pressure to ensure the problem isn't being caused by another fuel system component.
- Monitor engine performance
- Watch for symptoms such as hard starting, engine stalling, rough idling, poor acceleration, or inconsistent fuel delivery, as these can help narrow down the diagnosis.
- Avoid prolonged driving
- If the engine is running poorly or stalling, avoid driving until the issue is repaired to reduce the risk of further engine or fuel system damage.
- Replace the Fuel Control Module if necessary
- If testing confirms that the module has failed internally and all related components are functioning properly, replacing the Fuel Control Module is typically the most reliable solution.
Addressing Fuel Control Module problems early can help restore proper fuel system operation, improve engine reliability, and prevent more costly repairs. A complete diagnosis is always recommended to ensure the root cause is identified before replacing the module.
It is an electronic control module that manages fuel delivery and communicates with the engine control system to help maintain proper engine operation.
The 5664261 is commonly used on heavy-duty natural gas trucks, regional haul tractors, refuse trucks, transit buses, and vocational vehicles equipped with compatible Cummins ISX12G engines.
The module is engineered for continuous heavy-duty operation under high temperatures, engine vibration, electrical load fluctuations, and demanding commercial service conditions.
Technicians commonly inspect the module when diagnosing fuel system communication faults, engine performance concerns, module-related diagnostic trouble codes, electrical connection issues, or intermittent engine operation.



