CM2150 Electronic Control System – FAULT CODE 2646

Engine Coolant Temperature – Condition Exists


Overview

CODE REASON EFFECT
Fault Code: 2646
PID: P110
SPN: 110
FMI: 31
LAMP: Amber
SRT: 

Engine Coolant Temperature – Condition Exists. The EGR valve was closed to reduce engine coolant temperature.

EGR valve actuation will be disabled.

ISB, ISC, ISL – Engine Coolant Temperature Circuit
SMALL | MEDIUM | LARGE

Circuit Description

When the engine coolant temperature nears the engine protection limits, the exhaust gas recirculation (EGR) valve will be closed to reduce the coolant temperature. This fault code is used as an information fault code, only indicating that the EGR valve has closed.

Component Location

The engine coolant temperature sensor is located on the thermostat housing. Refer to Procedure 100-002 (Engine Diagrams) in Section E for a detailed component location view.

Conditions for Running the Diagnostics

This diagnostic runs continuously when engine speed is greater than 500 rpm.

Conditions for Setting the Fault Codes

The fault code is set active when the EGR valve is closed to reduce engine coolant temperature.

Action Taken When the Fault Code is Active

  • The ECM illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.

Conditions for Clearing the Fault Code

The fault code is set inactive when the EGR valve actuation is re-activated.

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.

When the engine coolant temperature nears the engine protection limits, the EGR valve will be closed to reduce the coolant temperature. This fault code is used as an information fault code, only indicating that the EGR valve has closed. No failure has occurred to cause this fault code. Other engine protection fault codes will be active if the engine coolant temperature has exceeded the engine protection limits.

Refer to Troubleshooting Fault Code t05-2646

Last Modified:  20-Jul-2010