New Holland 3109 – ECM: CC HS Power Stage 1 Fuel Pressure Control - No Signal

The Engine Control Module (ECM) has detected a loss of electrical signal to the CC HS Power Stage 1 driver circuit, which powers the fuel pressure control valve. This indicates an open circuit, a disconnected component, or a complete failure of the fuel pressure regulator itself. As a result, the ECM cannot control or monitor the fuel pressure, which will negatively affect the proper operation of the fuel pressure regulation system.

• T6.120
• T6.140
• T6.150
• T6.155
• T6.160
• T6.165
• T6.175
• T6.180
• T7.170
• T7.185
• T7.200
• T7.210
• T7.220
• T7.235
• T7.250
• T7.260
• T6020
• T6030
• T6050
• T6070
• T6080
• T7030
• T7040
• T7050
• T7060
• T8 Series
• T9 Series
• CR9040
• CR9060
• CR9070
• CR9080
• CR6.80
• CR6.90
• CR7.80
• CR7.90
• CX8070
• CX8080
• CX8090
• CX8.80
• CX8.90
• Maxxum
• Puma
• Steiger

1. 1

   Visually inspect the wiring harness and connectors between the ECM and the fuel pressure regulator for damage, chafing, corrosion, or loose pins

2. 2

   Check all fuses related to the ECM and engine control system to ensure none are blown

3. 3

   Verify the ECM has a stable power supply and a clean, tight ground connection to rule out voltage drops

4. 4

   Disconnect and reconnect the electrical connector for the fuel pressure regulator to ensure a secure connection and check for dirt or moisture

5. 5

   Perform a wiring harness continuity test using a multimeter on the signal and power wires between the ECM and the regulator to identify breaks, shorts to ground, or shorts to power

1. 1

   Safety First

   Before beginning any work on the fuel system, ensure the engine is off, the key is removed, and all pressure is relieved from the hydraulic circuits.

2. 2

   Clean the Work Area

   Thoroughly clean the area around the high-pressure fuel pump and common rail to prevent contamination of the fuel system.

3. 3

   Locate the Fuel Pressure Regulator

   The fuel pressure regulator (also known as a fuel metering unit) is typically mounted on the high-pressure fuel pump (e.g., Bosch CP3) or on the fuel rail itself. It will have a 2-pin electrical connector.

4. 4

   Disconnect and Remove

   Disconnect the electrical connector. Using the appropriate tool, carefully unscrew and remove the fuel pressure regulator from the pump or rail. Be prepared for a small amount of residual fuel to spill.

5. 5

   Install the New Regulator

   Lightly lubricate the O-rings on the new fuel pressure regulator with clean diesel fuel. Install the new regulator and tighten it to the manufacturer's specified torque.

6. 6

   Reconnect and Bleed the System

   Reconnect the electrical connector. It is advisable to replace the fuel filters at this time if their condition is unknown. Cycle the key several times without starting the engine to allow the electric lift pump to prime the system and build pressure.

7. 7

   Start the Engine and Check for Leaks

   Start the engine and let it idle. Carefully inspect the area around the new fuel pressure regulator for any signs of fuel leaks.

8. 8

   Clear Fault Codes

   Use a diagnostic tool, such as the New Holland Electronic Service Tool (EST), to clear the 3109 fault code from the ECM's memory.

9. 9

   Test Drive

   Operate the machine under various load conditions to ensure the fault does not return and that engine performance is restored.