Autocar Cummins ISX DEF Head Unit
AUTOCAR CUMMINS ISX 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 2321-11-1 ( OEM Part Number 602062 ). This part is primarily made for a Cummins ISX, and comes with a One Million Miles or One Year Warranty. For additional warranty info Click Here
Additional Notes: DEF Header, 297mm
OEM NUMBERS
| Primary OEM | 602062 |
| Additional OEM | 601965, 602062 |
ADDITIONAL DETAILS
| CONDITION | Remanufactured |
| UPC / Barcode | 00840490541016 |
| 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.
Dependable DEF system function comes from the Autocar Cummins ISX DEF Head Unit: OEM 602062, a direct-fit replacement for compatible Autocar trucks. Built to OEM specifications, this unit monitors diesel exhaust fluid level, temperature, and quality to help maintain emissions compliance and steady aftertreatment performance. Its durable construction is designed to withstand demanding operating conditions, protecting both the exhaust system and overall engine efficiency. By choosing an OEM DEF head unit, you reduce compatibility concerns and promote long-term reliability. This component is a proven solution for keeping Autocar Cummins-powered vehicles operating smoothly and without interruption.
PEOPLE ALSO ASKS | BLOG(S)
The DEF Head Unit with part number 602062 is a critical component in Autocar trucks equipped with Cummins ISX engines. It mounts on the DEF (Diesel Exhaust Fluid) tank and integrates several sensors and fluid management features to support the Selective Catalytic Reduction (SCR) emissions system.
What It Does in Your Vehicle
- Monitors DEF Fluid Level
- The head unit constantly tracks how much DEF is in the tank. This ensures the engine control module can alert the operator when fluid levels get low, preventing unexpected shutdowns or performance issues.
- Measures DEF Fluid Temperature
- DEF must be kept within a specific temperature range. This sensor checks the fluid’s temperature so the system can activate heaters or adjust operations if the DEF is too cold.
- Ensures Clean Fluid Supply
- Inside the unit is a screen or mesh that helps prevent debris and contaminants from entering the SCR system. Clean fluid protects sensitive components like the DEF injector and catalyst.
- Manages Suction and Return Flow
- The unit controls how DEF is drawn from the tank and, when necessary, how unused fluid is returned. This helps maintain system pressure and ensures smooth fluid delivery.
A properly functioning DEF Head Unit is essential for reliable emissions control. It helps keep your truck compliant with environmental regulations, avoids triggering engine derate or fault codes, and protects expensive components in the aftertreatment system. Regular inspection and replacement when needed can help you avoid downtime and costly repairs.
The DEF (Diesel Exhaust Fluid) head unit is a critical part of your emissions system. It measures DEF level, quality, and temperature and sends that data to the engine control module. If this unit fails, your vehicle may still run—but not for long, and not reliably.
Risks of Driving With a Bad DEF Head Unit
Driving with a faulty DEF head unit can lead to:
- False low-level readings
- Your dashboard may show an empty DEF tank, even when full, triggering warnings.
- Unexpected derates
- The system may reduce engine speed or limit throttle response, even if everything else is functioning properly.
- Failed emissions compliance
- A malfunctioning unit may prevent proper DEF dosing, leading to excess emissions.
- Persistent warning lights
- “Service DEF System” or check engine lights may appear frequently.
- Vehicle shutdowns
- Some vehicles will initiate shutdown procedures if the fault isn't addressed after multiple cycles.
While you can drive for a short time with a bad DEF head unit, doing so is not safe or recommended. Immediate diagnosis and replacement can prevent costly repairs and on-road failures.
It should be checked during regular service intervals or when DEF-related warnings appear.
Yes, it may lead to failed inspections and regulatory issues.
A constant false “empty” DEF tank reading despite having fluid.
Yes, replacing it restores accurate DEF monitoring and proper SCR operation.
Cummins DEF Head Units
