New Holland 1823 – Engine ECU: Speed Sensor 2 Out of Range (Upper Side)

The Engine Control Unit (ECU) has detected a signal from Sensor 2 that is higher than the expected maximum threshold. This indicates an excessively high speed reading or a voltage signal from the sensor that is outside its normal operating parameters on the high side. Depending on the machine model, 'Sensor 2' may refer to a primary/secondary engine speed sensor (crankshaft or camshaft) or a transmission/wheel speed sensor utilized by the engine controller.

• T4
• T5
• T6
• T7
• T8
• TS90
• TS100
• TS110
• TS115
• TS100A
• TS110A
• TS115A
• TS125A
• TS135A
• TM Series
• TM115
• TM190
• TG Series
• TG210
• TG305

1. 1

   Verify the fault code with a diagnostic tool to confirm that code 1823 is active or has been logged, and note any other associated fault codes for additional context

2. 2

   Locate the engine speed sensors (typically a crankshaft and camshaft sensor) and any relevant transmission speed sensors, then visually inspect the sensor bodies for any signs of physical damage, such as cracks or breaks

3. 3

   Examine the wiring harness connected to the sensor for fraying, cuts, melting, or abrasion, especially near hot or moving parts

4. 4

   Check the electrical connector for corrosion, bent or pushed-back pins, and ensure it is securely latched

5. 5

   Carefully clean any metal shavings, grease, or debris from the sensor tip and the tone ring, and visually inspect the tone ring for any damaged, bent, or missing teeth

6. 6

   With the ignition on (engine off), back-probe the sensor's electrical connector to check for the correct supply voltage (often a 5V or 12V reference signal); no voltage could indicate a wiring fault or an issue with the ECU's power supply

7. 7

   Measure the resistance between the sensor's ground wire and a known good chassis ground; a high resistance reading (typically over 5 Ohms) indicates a poor ground connection

8. 8

   If possible, measure the sensor's output signal while the engine is cranking or running to check for a proper waveform or frequency, noting this may require an oscilloscope for accuracy

1. 1

   Disconnect battery

   Before beginning any repair, disconnect the battery to prevent electrical damage.

2. 2

   Remove faulty sensor

   Locate the suspect speed sensor. Remove any obstructing components (such as a hydraulic filter) if necessary to gain access, then remove the sensor.

3. 3

   Inspect and clean

   Re-inspect the tone ring for damage and ensure the sensor mounting surface is completely clean before installing the new part.

4. 4

   Install new sensor

   Thread in the new sensor and tighten it to the manufacturer's specification. Ensure any O-rings or seals are correctly seated to prevent leaks.

5. 5

   Reconnect components

   Securely fasten the electrical connector, ensuring it clicks into place. Re-install any components that were removed to gain access.

6. 6

   Clear codes and test

   Reconnect the battery. Use a diagnostic tool to clear the fault code from the engine controller. Start the tractor and perform a test drive to verify accurate speedometer readings, correct transmission shifting, and that the code does not return. Perform a transmission or system calibration if required for your specific model.