NUT 3K0846 - Caterpillar

System Operation Description:Use this procedure to troubleshoot the electrical system if a problem is suspected with the sensor. Also use this procedure if any one of the diagnostic codes in Table 1 is active or easily repeated.
Table 1
Diagnostic Codes
CDL Code and Description Conditions which Generate this Code System Response
3134-3
Aftertreatment #1 SCR Catalyst Reagent Tank #1 Temperature Sensor:Voltage Above Normal The code is for the main tank temperature sensor.
The Electronic Control Module (ECM) detects a signal voltage that is not in the acceptable range. The code is logged.
The value of the parameter is set to a default value.
Dosing is disabled until the pressure is correct.
3134-4
Aftertreatment #1 SCR Catalyst Reagent Tank #1 Temperature Sensor:Voltage Below Normal The code is for the main tank temperature sensor.
The ECM detects a signal voltage that is not in the acceptable range. System OverviewThe sensor signal for the passive sensor is routed from the ECM to terminal 1 of each sensor connector. The sensor return for the passive sensors is routed from the ECM to terminal 2 of each sensor connector.Diagnostics on the Caterpillar Electronic Technician (ET)Wiggle Test - The Wiggle Test allows you to monitor the status of the signals from the sensors.For additional information regarding the Wiggle Test, refer to the documentation that accompanies the Cat ET software.
Illustration 1 g03550823
Schematic for the passive sensors
Illustration 2 g01155187
Terminal locations at the connector for the passive analog sensors
(Terminal 1) Sensor signal
(Terminal 2) Analog return Test Step 1. Check for Diagnostic Codes
Connect Cat ET to the service tool connector.
Turn the keyswitch to the ON position.
Access the "Active Diagnostic Code" screen on Cat ET.
Look for these active codes or logged codes:
-3
-4Results:
Logged Code - A diagnostic code is logged. Proceed to Test Step 4.
Active -3 - A -3 diagnostic code is active. Proceed to Test Step 2.
Active -4 - A -4 diagnostic code is active. Proceed to Test Step 3.Test Step 2. Create a Short at the Sensor Connector
Turn the keyswitch to the OFF position.
Disconnect the suspect sensor.
Install the jumper wire between terminal 1 (sensor signal) and terminal 2 (sensor return) at the sensor connector.
Turn the keyswitch to the ON position.
Monitor the diagnostic codes on Cat ET. Check for an active -4 diagnostic code