2005 Mack ASET will not run.

[Joey Mack]

Hey  TechTy28    where you at???  

[Nickdieselz]

It sounds like you're dealing with a challenging diagnostic issue, especially given that the customer has already replaced multiple components. Based on the information you provided:

1. Unit Pump Codes: If you're seeing every unit pump code when it runs briefly on starting fluid, it's likely pointing to a fuel system issue. If even one of the unit pumps (individual cylinder fuel pumps) is shorted or malfunctioning, it could cause a no-start condition or erratic behavior across the entire fuel injection system. Since you're not seeing any exhaust smoke, it suggests fuel is not making it into the cylinders, further pointing to a possible fuel injection issue.

2. Single Unit Pump Shorting: Yes, a single shorted or faulty unit pump can disrupt the operation of the whole system. These pumps are often wired in series or share common circuits, and if one is shorting, it could cause the ECU to shut down the whole fuel injection system for protection, resulting in a no-start condition.

3. RPM Signal & Crank Mode: Since you’re getting an RPM signal in crank mode and have replaced the flywheel and cam sensors, it suggests that the basic engine management sensors are functioning properly. The issue seems more isolated to fuel delivery beyond the fuel supply pump, especially since you're not getting any injection happening (no exhaust smoke).

Things to Consider:
- Unit Pump Electrical Checks: You can check the wiring and resistance of each unit pump individually to see if one is shorted or out of spec. Compare readings to what’s expected for the system.
  
- Fuel Injector Control Module (FICM): If the unit pumps seem fine, the issue could also be in the FICM or another component of the fuel control system. The FICM controls the fuel injectors and could be malfunctioning.

- Injector Solenoids: Ensure the injector solenoids aren't stuck or faulty. A solenoid short or malfunction can also cause issues like this.

- Fuel Rail Pressure Sensor/Regulator: Though you've tested the fuel pressure during cranking, it’s worth double-checking that the rail pressure sensor and regulator are functioning correctly to avoid inconsistent pressure.

Since the truck runs briefly on starting fluid, it confirms spark and basic engine mechanics are working, so focusing on the fuel delivery and control system is key here. Checking wiring for shorts or grounding issues in the fuel system might lead you to the culprit.

[bgblk1968]

The ficm is built into the ecm correct? The older vmac 1 had a separate ficm in passenger kick panel?

[Joey Mack]

I dont think its a FICM anymore. Just part of the program in the EECU. 

[bgblk1968]

And am I overlooking, but is there not an ignition feed for this ecm? Getting back on this tomorrow, but looking over wiring diagram, what cuts it on and off?

[Joey Mack]

Fuse 40 in the fuse box under the hood. Did i not post the pin out chart for you? 

[Joey Mack]

Is this an ASET -I or CEGR?