RETAINER 4K6810 - Caterpillar

Note: Verify that the DPF does not need to be serviced for ash before performing this procedure. Refer to Troubleshooting, "Diesel Particulate Filter Has High Ash Load".The Engine Control Module (ECM) monitors the differential pressure across the Diesel Particulate Filter (DPF). The differential pressure should remain within a particular range. The range is based on a map within the ECM.
Table 1
Diagnostic Trouble Codes for High Differential Pressure
J1939 Code Description Information that Relates to the Code
3251-16 Diesel Particulate Filter Differential Pressure (bank 1) : High - Moderate Severity (2) The differential pressure has exceeded the trip point. The trip point varies. The trip point depends on the exhaust gas temperature and the amount of exhaust gas flow.
Engine power is derated. The code can not be cleared until the power to the ECM is cycled. A regeneration may be performed by using the dash switch (if equipped) or by the Caterpillar Electronic Technician (ET).
3285-16 Diesel Particulate Filter Differential Pressure (bank 2) : High - Moderate Severity (2)
3251-0 Diesel Particulate Filter Differential Pressure (bank 1) : High - Most Severe (3) The differential pressure has reached a very high level. The trip point varies. The trip point depends on the exhaust gas temperature and the amount of exhaust gas flow.
Engine power is derated 100 percent. Factory passwords are required in order to clear the code. A "service test" regeneration is the only type of regeneration that can be performed.
3285-0 Diesel Particulate Filter Differential Pressure (bank 2) : High - Most Severe (3)
Follow the troubleshooting procedure in order to identify the root cause of the problem.
Table 2
Diagnostic Trouble Codes for Low Differential Pressure
J1939 Code Description Information that Relates to the Code
3251-18 Diesel Particulate Filter Differential Pressure (bank 1) : Low - Moderate Severity (2) The differential pressure is below the trip point. The trip point varies. The trip point depends on the exhaust gas temperature and the amount of exhaust gas flow.
Engine power is derated. The Aftertreatment Regeneration Device (ARD) is deactivated. The Clean Gas Induction System (CGI) is turned off. The code can not be cleared until the power to the ECM is cycled. The following conditions can cause these codes:
There is a problem with the tubing between the DPF and the sensor group for the DPF.
There is a problem with the exhaust piping between the engine and the DPF.
3285-18 Diesel Particulate Filter Differential Pressure (bank 2) : Low - Moderate Severity (2)
Follow the troubleshooting procedure in order to identify the root cause of the problem. Troubleshooting Procedure for High Differential Pressure
If the vehicle is equipped with an ARD disable switch, verify that the switch is not disabling the ARD. Refer to the vehicle's service manual in order to determine the proper operation of the switch.
Troubleshoot any diagnostic codes that relate to the following systems or conditions:
Low boost
ARD
CGITroubleshoot the systems in the order that is listed above if there are diagnostic codes for more than one of the systems.
If the ARD disable switch was not disabling the ARD and there are