CM871 and CM876 Electronic Control Systems, ISX and ISM Engines – FAULT CODE 1895

EGR Valve Controller – Bad Intelligent Device or Component

Overview

CODE	REASON	EFFECT
Fault Code: 1895 PID: S146 SPN: 2791 FMI: 12/12 LAMP: Amber SRT:	EGR Valve Controller – Bad Intelligent Device or Component. A calibration mismatch between the EGR valve and the ECM has been detected.	EGR valve actuation will be disabled.

ISX – EGR Valve Circuit SMALL | MEDIUM | LARGE

ISM – EGR Valve Circuit SMALL | MEDIUM | LARGE

Circuit Description

The exhaust gas recirculation (EGR) valve is a smart device and receives commands from the engine electronic control module (ECM) via the J1939 datalink. The EGR valve performs its own internal diagnostics and reports failures back to the primary engine electronic control module (ECM) using the J1939 datalink.

The EGR valve is opened by a motor located on top of the EGR valve. A pin is extended from the motor and contacts the dual-poppet valve to open the EGR valve. The EGR valve motor is not used to close the EGR valve. The pin retracts and a spring is used to close the EGR valve.

This fault code is logged when the calibration version contained in the EGR valve is mismatched with the version in the ECM.

Component Location

The EGR valve location can vary depending on the engine application. Refer to Procedure 100-002 (Engine Diagrams) in Section F for a detailed component location view.

Conditions for Running the Diagnostics

This diagnostic runs continuously when the keyswitch is in the ON position or when the engine is running.

Conditions for Setting the Fault Codes

• The ECM has detected a calibration incompatibility between the EGR valve and the ECM calibration.
• The ECM has detected an incorrect EGR valve installed on the engine.

Action Taken When the Fault Code is Active

• The ECM illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.
• The EGR valve will stop responding to commands and the spring will close the EGR valve.

Conditions for Clearing the Fault Code

The ECM will turn off the amber CHECK ENGINE light and clear the fault code after the keyswitch is cycled and the diagnostic runs and passes.

Shop Talk

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If necessary, recalibrate the ECM. Refer to Procedure 019-032 (ECM Calibration Code) in Section 19 in the corresponding Troubleshooting and Repair Manual for the engine being serviced.

This fault code is logged when the ECM has detected an incorrect EGR valve has been installed on the engine.

Refer to Troubleshooting Fault Code t05-1895