5031948 JOHNSON SCREW

Table 1
Diagnostic Codes Table for Soot Sensor
J1939 Code CDL Code Code Description
(code descriptions may vary) Comments
4783-3 3397-3 DPF #1 Mean Soot Signal : Voltage Above Normal The Electronic Control Module (ECM) detects the following conditions:
The signal voltage for the soot sensor is greater than 32 VDC for 60 seconds.
The warning lamp will come on. The ECM will log the diagnostic code.
The EBPR may close as a precaution.
4783-4 3397-4 DPF #1 Mean Soot Signal : Voltage Below Normal The Electronic Control Module (ECM) detects the following conditions:
The signal voltage for the soot sensor is less than 9 VDC for 60 seconds.
The warning lamp will come on. The ECM will log the diagnostic code.
The EBPR may close as a precaution.
4783-12 3397-12 DPF #1 Mean Soot Signal : Failure The ECM detects the following conditions:
The soot sensor has failed.
The warning lamp will come on and the ECM will log the diagnostic code.
4783-21 3397-21 DPF #1 Mean Soot Signal : Data Drifted Low The ECM detects the following conditions:
The signal received from the soot sensor has been too low to be valid for a correctly installed sensor.
The warning lamp will come on and the ECM will log the diagnostic code.
Table 2
Required Tools
Tool Part Number Part Description Qty
A 366-7782 Attenuator 1 The following conditions must exist before any of the preceding codes will become active:
The ECM has been powered for at least 60 seconds.
There are no active 168 codes.The following background information is related to this procedure:The soot sensor is powered from the switched battery voltage. A signal is sent by the soot sensor to one soot antenna. The signal that is received by the other antenna is sent back to the soot sensor. The signal is attenuated by the soot in the Diesel Particulate Filter (DPF). The ECM calculates the soot load in the DPF by using the attenuation information received from the soot sensor.
Illustration 1 g03812262
Schematic diagram for the soot sensor circuit
Illustration 2 g03812265
View of the pin locations on the P1 connector for the soot sensor
(17) CAN C +
(18) CAN C -Complete the procedure in the order in which the steps are listed.
Table 3
Troubleshooting Test Steps Values Results
1. Inspect Electrical Connectors and Wiring
A. Turn the keyswitch to the OFF position.
B. Inspect the connectors for the soot sensor. Refer to Troubleshooting, "Electrical Connectors - Inspect".
C. Perform a 45 N (10 lb) pull test on each of the wires in the suspect sensor connector and the sensor connections at the ECM.
D. Check the screw for the ECM connector for the correct torque of 6 N m (53 lb in).
E. Check the ground connection on the ECM for abrasions and pinch points.
F. Check the harness for abrasion and pinch points from the suspect sensor to the ECM.
G. Check that the suspect sensor is installed correctly. Check that the suspect sensor is fully seated into the engine.
Loose connection or damaged wire
Result: There is a fault in a connector or the wiring.
Repair: Repair any faulty connectors or replace the wiring harness. Ensure that all the seals are properly in place and ensure that the connectors are correctly coupled.
Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.
Result: All connectors, pins, and sockets are correctly coupled and/or inserted. The harness is free of corrosion, abrasion, and pinch points.
Repair: There may be an intermittent fault. Use the electronic service tool to perform a Wiggle Test. If no fault is identified
If no fault is identified, proceed to Test Step 2.
2. Check For Active Diagnostic Codes
A. Turn the keyswitch to the OFF position.
B. Connect the electronic service tool to the diagnostic connector.
C. Turn the keyswitch to the ON position. Download the "Product Summary Report" from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes.
D. Use the electronic service tool to monitor active diagnostic codes or recently logged diagnostic codes. Look for an active or logged code.
E. Turn the keyswitch to the OFF position.
Diagnostic codes
Result: Diagnostic code 4783-3 or 3397-3 is active.
Proceed to Test Step 3.
Result: Diagnostic code 4783-4 or 3397-4 is active.
Proceed to Test Step 4.
Result: Diagnostic code 4783-12 or 3397-12 is active.
Proceed to Test Step 5.
Result: Diagnostic code 4783-21 or 3397-21 is active.
Proceed to Test Step 6.
3. Check for a High Voltage at the Soot Sensor
A. Turn the keyswitch to the ON position.
B. Measure the voltage across pins 1 and 2 on the soot sensor connector.
C. Turn the keyswitch to the OFF position.
Greater than 32 VDC
Result: The supply voltage is within the acceptable range for the soot sensor.
Return the unit to service
Result: The supply voltage is above the acceptable range for the soot sensor.
Repair: Investigate the cause of the high voltage. Refer to Systems Operation, Testing and Adjusting, "Charging System - Inspect".
4. Check for a Low Voltage at the Soot Sensor
A. Turn the keyswitch to the ON position.
B. Measure the voltage across pins 1 and 2 on the soot sensor.
C. Turn the keyswitch to the OFF position.
Less than 9 VDC
Result: The supply voltage is within the acceptable range for the soot sensor.
Return the unit to service.
Result: The supply voltage is below the acceptable range for the soot sensor.
Repair: Make sure that any in-line fuses are intact. Replace any blown fuses.
Check that the supply voltage is adequate. Refer to Systems Operation, Testing and Adjusting, "Charging System - Inspect".
If the supply voltage is satisfactory, inspect the wiring and the connectors. Refer to Troubleshooting, "Electrical Power Supply - Test".
5. Diagnostic Code 4783-12 or 3397-12 is Active
A. If diagnostic code 4783-12 or 3397-12 is active, the soot sensor has a fault.
Faulty sensor
Result: Diagnostic code 4783-12 or 3397-12 is active. T