Cummins ISB 23-Pin Wiring Diagram | ECM Pinout, VP44 Fuel System, Sensors & J1939 Network (Bulletin 3666325)

Technical Highlights

• Full 23-pin OEM connector + ECM connector pinout
• VP44 fuel system integration:
  • Fuel pump control module
  • Fuel shutoff
  • Data link communication
• Sensor circuits:
  • Engine speed & position sensors
  • Oil pressure sensor
  • Intake manifold pressure
  • Ambient air pressure
  • Coolant temperature
• Throttle & control systems:
  • Accelerator position sensor (+5V, signal, return)
  • Idle validation signals
  • Cruise control & PTO functions
• Communication:
  • J1939 data link
  • J1587 service data link
• Diagnostic systems:
  • Red, yellow, maintenance lamps
  • Wait-to-start & water-in-fuel indicators
• Actuators:
  • Lift pump
  • Fan clutch
  • Cold start aid relay
• Power distribution:
  • Battery supply, ignition, and fuse protection

👉 The diagram on page 1 clearly maps ECM connections to VP44 system, sensors, and OEM interface through the 23-pin connector, including full signal routing and connector views.

Table of Content

• ECM & 23-Pin Connector Layout
• VP44 Fuel System Wiring
• Sensor Network (Pressure / Temperature / Speed)
• Accelerator & Idle Validation System
• Cruise Control & PTO Circuits
• Diagnostic Lamps & Indicators
• Data Link Communication (J1939 / J1587)
• Actuator Control (Lift Pump, Fan Clutch)
• Power Supply & Ground Distribution

File Information

• Manufacturer: Cummins
• System: ISB Engine Management
• Connector Type: 23-Pin OEM Interface
• Fuel System: VP44
• Document Type: Wiring Diagram
• Bulletin: 3666325-02
• Format: PDF
• Pages: 1
• Content: Electrical Schematics, Pinout, Fuel & Sensor Systems