E-ONE Cummins ISL DEF Head Unit
E-ONE CUMMINS ISL DEF HEAD UNIT
ORDERS PLACED BEFORE 3PM EST WILL SHIP SAME DAY
WARRANTY
1M MILES OR 1 YEAR
PRODUCT DESCRIPTION
This is a Remanufactured, Tamerx DEF Head Unit, Tamerx part number 5410-11-FA01-9 ( OEM Part Number 723035 ). This part is primarily made for a Cummins ISL, and comes with a One Million Miles or One Year Warranty. For additional warranty info Click Here
Additional Notes: DEF Header, 40 MICRON, 11"
OEM NUMBERS
| Primary OEM | 723035 |
| Additional OEM | 719006, 723035 |
ADDITIONAL DETAILS
| CONDITION | Remanufactured |
| UPC / Barcode | 00840490541788 |
| WEIGHT | 8.00 LBS |
SHIPPING OPTIONS
Ship Weight : 8.00 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.
The E-ONE Cummins ISL DEF Head Unit OEM 723035 is a genuine factory component designed to maintain reliable Diesel Exhaust Fluid system operation in Cummins-powered E-ONE emergency vehicles. Built to strict OEM specifications, it provides precise fitment and dependable functionality under demanding service conditions. By supporting proper DEF performance, this unit helps ensure compliance with emissions standards while allowing engines to operate smoothly and consistently. Its rugged construction is engineered for durability, delivering long-lasting service life in critical-response applications. For fire departments and operators, this DEF head unit offers OEM-backed quality and trusted reliability when it matters most.
PEOPLE ALSO ASKS | BLOG(S)
E-ONE emergency vehicles equipped with Cummins ISL engines are designed to operate reliably under demanding conditions. To meet emissions requirements, these vehicles use a Selective Catalytic Reduction (SCR) system that depends on Diesel Exhaust Fluid (DEF). At the center of this system is the DEF Head Unit OEM 723035, a vital component that manages and monitors DEF within the tank.
Core Role
The primary role of the DEF Head Unit OEM 723035 is to act as the monitoring and control hub for the DEF system. It combines several functions into a single assembly to ensure DEF is always available, in good condition, and delivered properly to the SCR system.
What It Does
- Monitors DEF Level
- Tracks how much DEF is in the tank and communicates with the engine control module (ECM).
- Measures Temperature
- Keeps watch on fluid temperature to avoid freezing or overheating issues.
- Manages Fluid Flow
- Provides pickup and return ports that keep DEF circulating between the tank and the dosing system.
- Protects with Filtration
- Includes a filter or strainer to prevent contaminants from damaging sensitive components.
- Communicates with ECM
- Sends real-time data that allows accurate dosing and fault detection.
Without the DEF Head Unit OEM 723035, the Cummins ISL SCR system could not function properly. By ensuring proper DEF monitoring and flow, this unit helps E-ONE vehicles remain compliant with emissions standards while maintaining reliability in critical service situations.
The DEF (Diesel Exhaust Fluid) head unit is responsible for monitoring fluid level, quality, and temperature. When it begins to fail, your truck will send warning signs that shouldn’t be ignored. Recognizing these symptoms early can help prevent costly breakdowns and downtime.
Common Symptoms of a Failing DEF Head Unit
If your DEF head unit is going bad, you may notice:
- DEF system fault codes
- appearing on the dashboard
- Check engine light
- triggered by emissions errors
- Inaccurate DEF readings,
- such as showing low or empty when the tank is full
- Premature derate countdowns,
- restricting mileage and operation time
- Vehicle entering limp mode,
- reducing speed to 5 mph or less
- Intermittent warnings,
- with alerts that appear and disappear unexpectedly
The head unit communicates directly with the engine control module. When sensors fail, the system assumes the emissions equipment is not working correctly. To remain compliant, the truck limits operation until the problem is fixed.
A failing DEF head unit should never be ignored. If you notice any of these symptoms, it’s best to schedule service or replacement immediately to avoid being stranded in derate mode.
It provides accurate DEF system data to keep emissions controls functioning properly during operation.
Yes, a failed unit may trigger derate mode that limits engine output.
Yes, it is engineered for E-ONE vehicles powered by Cummins ISL engines.
It transmits DEF level, quality, and temperature readings from the tank.
Cummins DEF Head Units
