0912078 JOHNSON SHOULDER SCREW, 1-1/2"

Table 1
J1939 Code and Description CDL Code and Description Comments
411-15
High EGR Differential Pressure E1094 (1)
High EGR Differential Pressure The ECM detects an abnormally high reading from the NRS differential pressure sensor.
411-17
Low EGR Differential Pressure E1093 (1)
Low EGR Differential Pressure The ECM detects an abnormally low reading from the NRS differential pressure sensor.
2659-15
High EGR Mass Flow Rate E1096 (1)
High EGR Mass Flow Rate The ECM detects a higher than desired flow rate through the NRS
2659-17
Low EGR Mass Flow Rate E1095 (1)
Low EGR Mass Flow Rate The Electronic Control Module (ECM) detects a lower than desired flow rate through the NRS
2791-5
EGR Valve Control : Current Below Normal 3405-5
EGR Valve Control : Current Below Normal This code indicates that there is an electrical problem with the solenoid valve and/or circuit on the NOx Reduction System (NRS) valve actuator.
2791-6
EGR Valve Control : Current Above Normal 3405-6
EGR Valve Control : Current Above Normal This code indicates that there is an electrical problem with the solenoid valve and/or circuit on the NRS valve actuator.
3358-16
EGR Inlet Pressure : High - moderate severity (2) E1090 (2)
High EGR Intake Pressure The ECM detects a higher than desired EGR Intake Pressure
Table 2
Associated Code
CDL Code WCI
E1092 (2)
Illustration 1 g02138942
Location of the NRS actuator solenoid
Note: Exhaust Gas Recirculation (EGR) is a term used to describe the recirculation of exhaust gas through the engine as a means to reduce "NOx" emissions. Caterpillar has elected to refer to this system as the NOX Reduction System (NRS). Diagnostic codes are regulated by SAE. The diagnostic codes will reflect the EGR nomenclature.
Illustration 2 g02138941
Schematic for the NRS valve actuator
Table 3
Troubleshooting Test Steps Values Results
1. Perform Pressure Sensor Calibration
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Turn the keyswitch to the ON position. Allow 30 seconds for a calibration of the engine pressure sensors to be performed by the ECM.
C. Check for diagnostic trouble codes that are associated with the sensor calibration.
D. Turn the keyswitch to the OFF position.
Codes
Result: There are no active -13 codes currently.
Proceed to Test Step 2.
Result: Either a 1785-13, or a 3387-13 is active.
Repair: Perform another calibration attempt, follow these instructions closely:
1. Turn the keyswitch to the OFF position. Allow the keyswitch to remain in the OFF position for ten minutes.
2. Turn the keyswitch to the ON position. Allow 30 seconds for the ECM to attempt a calibration of the sensor.
3. Turn the keyswitch to the OFF position. Allow the keyswitch to remain in the OFF position for 30 seconds.
Note: Do not use the battery disconnect switch to power-down the ECM. Ensure that the unswitched battery power to the ECM remains on so that the calibration data can be saved to internal memory.
4. Turn the keyswitch to the ON position. Check for diagnostic trouble codes that are associated with the sensor calibration.
If the original code is still active, replace the appropriate sensor. Check for the recurrence of the diagnostic codes to verify that the problem is resolved.
If the problem is not resolved, proceed to Test Step 2.
2. Check for Associated Codes
A. Establish communication between Caterpillar Electronic Technician (ET) and the service tool connector.
B. Determine if an associated code is active or logged.
Associated Codes
Result: No associated codes are active or logged.
Proceed to Test Step 3.
Result: There are associated codes that are active or logged.
Repair: Troubleshoot associated codes prior to continuing with this procedure. Refer to Troubleshooting, "Event Codes" to troubleshoot the associated diagnostic code.
If the problem is not resolved, proceed to Test Step 3.
3. Check for Codes
A. Connect Cat Electronic Technician (ET) to the service tool connector.
B. Determine if a code is active or logged.
Codes
Result: A 3405-5 code is active.
Proceed to Test Step 13.
Result: A 3405-6 is active.
Proceed to Test Step 12.
Result: A E1090(2) is logged or active.
Proceed to Test Step 6.
Result: A E1090(2) and E1095(2) or E1095(1) are active or logged.
Proceed to Test Step 6.
Result: E1090(2), E1093(1), E1093(2) and/or E1904(1), E1094(2) is active or logged.
Proceed to Test Step 8.
Result: E1095(1), E1095(2) and/or E1096(1), E1096(2) is active or logged.
Proceed to Test Step 4.
Illustration 3 g02149542
Inspection points for the exhaust piping for the NRS that is on the top of the engine
Table 4
Troubleshooting Test Steps Values Results
4.