New Holland ENG 3118 – Engine Control Module (ECM): ECM 12V Sensor Supply Voltage High

This fault code indicates that the 12-volt sensor supply voltage originating from the Engine Control Module (ECM) is reading higher than the acceptable maximum threshold. This specific code is triggered when the ambient pressure sensor inside the ECU is defective.

• T6 Series
• T7 Series
• T8 Series
• T8.330
• T8.390
• B90B
• B95B
• B110B
• B115B
• LB75
• CR Series
• CR9040
• CR9060
• CR9070
• CR9080
• CR9090
• CX Series
• CX8080
• CX8090
• D85B
• D95B
• D150B
• F104B
• F170B

1. 1

   Assess machine configuration and environment to determine if the machine operates at high altitudes or if the engine is equipped with a Variable Geometry Turbocharger (VGT).

2. 2

   Verify symptoms to see if the machine is experiencing derating, stalling, or erratic acceleration. If not, the fault may be purely related to the internal ambient pressure sensor failing without affecting base fuel delivery at sea level.

1. 1

   Determine if Replacement is Necessary

   The official CNH service manual explicitly states: 'Replace ECU (not necessary if never running in high altitude and if turbocharger without VGT)'. If the machine operates at low altitudes and uses a standard turbocharger, you may safely ignore the code and continue operation.

2. 2

   ECU Replacement (If Required)

   If the machine requires accurate ambient pressure readings for a VGT or high-altitude fueling adjustments, the ECM must be replaced.

3. 3

   Remove the ECM

   Disconnect the battery, then carefully unplug the harness connectors from the Bosch EDC7 module and unbolt it from the engine block/mounting bracket.

4. 4

   Clone / Flash the New ECM

   A replacement ECM cannot simply be plugged in. It must be programmed using the CNH Electronic Service Tool (EST) or cloned by a specialized ECU repair service so that the immobilizer data, software version, and dataset match the original tractor.

5. 5

   Reinstall and Clear Codes

   Install the programmed ECM, reconnect the battery, and use the diagnostic tool to clear the inactive ENG 3118 code.