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√ DATA ERROR on AUX Temp (Auxiliary Temperature) and Settings on Caterpillar ET Software

AUX Temp (Auxiliary Temperature) 

AUX Temp Sensor is optional equipment, with CAT P/N 370-3830.
-Additional installed for the Zone 2 Area or Hazardous Location, 
-Installed on Explosion Protection Engine Kit (such as "Pyroban") at Exhaust Manifold.
Figure 1.1 - DATA ERROR (Aux Temp)

Troubleshoot AUX Temp - DATA ERROR
Check/measuring the resistance of AUX Temp Sensor (2-cables), Std: approx. 40K ohms.
If measured:
  • "0 ohm" it means Shorted (damaged), with Diagnostic Code: SPN 441 - FMI 4 (CID 1836-4)
  • "M ohm" (no resistance) it means Open (damaged), with Diagnostic Code: SPN 441 - FMI 3 (CID 1836-3). Read More: Sensor Diagnostics on Electronic Engines.
Figure 1.2 - SPN 441 FMI 3 (Murphy PowerView)
Figure 1.3 - SPN 441 FMI 3 (1836-3)
  • Replace with new AUX Temp Sensor, done.

Setting "High Auxiliary Temperature" - Warning/ Shutdown Message
Figure 1.4 - Monitoring System
  • Click on "High Auxiliary Temperature", and set on Trip Point (Deg F) tab.
Figure 1.5 - High Auxiliary Temperature (State: On)
  • When actual reading on AUX Temp sensor reached the Trip Point (Deg F), will displays Event Code: SPN 441 - FMI 15 (E445). To disabled, set on "State" tab from "On" to "Off".
Figure 1.6 - State (Off)
Figure 1.7 - High Auxiliary Temperature (State: Off)


Setting Disabled (NO DATA) - Auxiliary Temperature Sensor Installation Status, to Clear Error Code SPN 441
  • Click on "Service", then "Configuration Tool".
Figure 1.8 - Configuration Tool
  • Click Expand All, and click on "Auxiliary Temperature Sensor Installation Status".
Figure 1.9 - Auxiliary Temperature Sensor Installation Status
  • Change "Current Value" from "Installed" to "Not Installed" and click "OK", then click "Yes".
Figure 2.1 - Auxiliary Temperature Sensor Installation (Not Installed)
  • Need to restart the power supply to the ECM, after change has been made.

Note: Please keeps monitoring "Exhaust Back Pressure" through manual gauge, or Auxiliary Pressure Sensor (if installed), when you disabled this optional setting.

Exhaust Back Pressure