Autocar Cummins ISX DEF Head Unit

Reliable DEF Control for Heavy-Duty Operation: Autocar Cummins ISX DEF Head Unit

What is it?
The Autocar Cummins ISX DEF Head Unit is a critical assembly for the Diesel Exhaust Fluid (DEF) system on Autocar trucks powered by the Cummins ISX engine. It combines a fluid control valve, filters, heater, sensors (level/temperature/quality) and wiring interface to manage DEF delivery and monitor fluid state for the Selective Catalytic Reduction (SCR) system.

Why Choose the Autocar Cummins ISX DEF Head Unit?
This unit is built to OEM specification for Autocar ISX installations. That means proper mounting geometry, correct sensor interfaces, accurate flow control and full compatibility with emissions system diagnostics. Using a properly matched DEF head unit reduces fitment issues, avoids false warnings and supports long-term reliability of the after-treatment system. 

Key Benefits
✅ Factory-Compatible Fit: Designed specifically for Autocar ISX applications with correct mounting and connections.
✅ Comprehensive Sensor & Control Integration: Monitors fluid level, temperature, quality and ensures proper flow to the SCR system.
✅ Reduced Risk of Downtime: Matching OEM form and function helps prevent DEF-system faults and engine derates.
✅ Durable Construction: Suited for heavy-duty truck environments—vibration, high thermal cycling and continuous duty.
✅ System Protection: Accurate DEF control helps extend the life of downstream catalysts, sensors and exhaust components.

Applications
This DEF head unit is intended for Autocar trucks equipped with Cummins ISX engines (model years corresponding to the component) where the emissions system employs DEF and SCR control. Ideal for heavy-duty hauling, vocational use and commercial fleet service requiring dependable emissions operation.

Installation Notes
Installation should be performed by a qualified technician. Begin by confirming compatibility with your Autocar chassis, Cummins ISX engine model and the correct part number for your application. De-energize the DEF system, relieve any pressure and drain the tank if required. Remove the existing head unit carefully, paying attention to sensor wiring, DEF fluid lines, heater elements and mounting hardware. Clean all mating surfaces, inspect or replace gaskets/seals, mount the new unit with correct orientation, and torque bolts as manufacturer specifies. Reconnect all sensors, wiring and fluid plumbing, clear any diagnostic trouble codes and perform an operational test—checking DEF system functionality, flow accuracy and absence of leaks or warnings.

Final Thoughts
In modern emissions-regulated heavy-duty vehicles, the DEF head unit is a cornerstone part of the after-treatment system. The Autocar Cummins ISX DEF Head Unit offers an OEM-matched, reliable replacement option designed to restore proper DEF control, keep your SCR system functioning efficiently and help maintain uptime and compliance for your Autocar-powered rig.