New Holland 146 – ECM: Engine Coolant Temperature Exceeded Warning Limit

The Engine Control Module (ECM) has detected that the engine coolant temperature has surpassed the pre-defined upper warning threshold. This fault triggers to protect the engine from damage caused by overheating. When active, the ECM typically reduces engine power output (derate), disables the Exhaust Gas Recirculation (EGR) valve operation, and may initiate an automatic engine shutdown if temperatures reach a critical level.

• T5 Series
• T6 Series
• T6.175
• T7 Series
• T7.210
• T7.270
• T8 Series
• T8.390
• TC Series
• TD Series
• TM Series
• TN Series
• TS Series
• CX Series
• CX8080
• CR Series
• CR9.90
• B95B
• B110B
• L230
• C238
• W130C
• W190C

1. 1

   Check coolant level in the reservoir and radiator to ensure it is not low

2. 2

   Inspect the radiator, charge air cooler, and cooling pack for external blockages, blowing out dust, chaff, and debris with compressed air

3. 3

   Inspect the cooling fan, fan belt tension, and viscous fan clutch engagement (a free-spinning fan when hot indicates failure)

4. 4

   Examine all radiator and coolant hoses for signs of collapse (especially the lower hose), cracking, or leaks

5. 5

   Check for internal radiator blockages by using an infrared thermometer to find significant cold spots on the radiator core

6. 6

   Verify gauge accuracy by comparing the dashboard reading with the actual temperature at the thermostat housing using an infrared thermometer or diagnostic tool

7. 7

   Check for excessive system loads, such as a stuck hydraulic relief valve, which can place constant strain on the engine

1. 1

   Relieve system pressure

   Ensure the engine is completely cool and relieve any pressure from the cooling system by slowly opening the radiator cap.

2. 2

   Locate the sensor

   Find the coolant temperature sensor on the engine block near the thermostat housing where the upper radiator hose connects, or on the cylinder head's water jacket.

3. 3

   Drain coolant partially

   Place a clean drain pan under the radiator and open the drain petcock to lower the coolant level to just below the sensor's position to minimize coolant loss.

4. 4

   Remove old sensor

   Disconnect the electrical wiring harness from the sensor and carefully unscrew and remove the old sensor using the appropriate wrench.

5. 5

   Install new sensor

   Clean the threads on the engine block, apply suitable thread sealant if recommended, thread the new sensor in by hand to avoid cross-threading, and tighten to the specified torque.

6. 6

   Refill and bleed system

   Reconnect the electrical connector, close the radiator petcock, and refill the cooling system. Start the engine with the radiator cap off and let it run to operating temperature to bleed air pockets. Top off coolant and replace the cap securely.

7. 7

   Verify repair

   Check that fault code 146 is no longer active and operate the machine under load to confirm the overheating issue is resolved.