Case IH 19061 (DTC 32BE) - ECU – Engine Control Module (ECM): Upstream NOx sensor lambda signal deviation - NOx sensor possible removal detected.

The system detects that the lambda (oxygen/fuel ratio) signal coming from the upstream NOx sensor is deviating significantly from the expected operational parameters. The deviation is severe enough that the system logic suspects the sensor has been physically removed from the exhaust stream, is improperly mounted, or has suffered a complete internal failure preventing it from reading the exhaust gases accurately.

• MAXXUM T4E
• 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Case IH Maxxum (6.7L engines)
• Puma
• Steiger (580)
• CVX series (110, 115, 130 CVX, 145 CVX, 160 CVX, 170, 185, 200, 215 CVX, 230 CVX)
• FPT engines (F5 T4B series)

1. 1

   Visual Inspection: Locate the upstream NOx sensor (before the DOC). Verify that the sensor is physically present, securely mounted, and has not backed out of its threaded bung.

2. 2

   Wiring and Connector Check: Inspect the sensor's 5-pin electrical connector (Connector C186) and the wiring harness leading back to the ECM. Look for melted wires, chafing, or corrosion that could cause signal deviation.

3. 3

   Voltage Check: Verify that the sensor is receiving proper supply voltage (typically a 24V system).

4. 4

   Check for Accompanying Codes: Look for related upstream NOx sensor codes that might indicate a specific electrical failure rather than a removal/deviation issue, such as 19060 (CAN timeout), 19062 (Values not plausible), 19063 (Supply voltage out of range), or 19051-19054 (Internal heater/circuit errors).

1. 1

   Preparation

   Turn off the engine, remove the key, and disconnect the battery to prevent electrical shorts. Allow the exhaust system to cool completely, as the DOC and surrounding pipes operate at extremely high temperatures.

2. 2

   Disconnect

   Locate the upstream NOx sensor (before the DOC). Disconnect the 5-pin electrical connector from the machine's wiring harness.

3. 3

   Removal

   Using a specialized NOx sensor socket or a suitable wrench, carefully unscrew the sensor from the exhaust pipe (M20 x 1.5 thread). If the sensor is seized, penetrating oil may be required.

4. 4

   Installation

   Apply a high-temperature anti-seize compound to the threads of the new NOx sensor (if it does not come pre-applied from the factory). Do not get anti-seize on the sensor probe itself.

5. 5

   Torque

   Thread the new sensor into the exhaust bung by hand to prevent cross-threading, then tighten it to the OEM specified torque.

6. 6

   Reconnect

   Route the sensor cable (typically ~890mm long) away from extreme heat sources and moving parts. Reconnect the 5-pin electrical connector.

7. 7

   Calibration/Reset

   Reconnect the battery. Connect a Case IH diagnostic tool (EST) to the machine. Clear the inactive 19061 / 32BE fault code. Depending on the exact engine software, you may need to run an aftertreatment reset or NOx sensor calibration routine so the ECM recognizes the new sensor.