CM2150 Electronic Control System – FAULT CODE 197

Coolant Level – Data Valid but Below Normal Operational Range – Moderately Severe Level


Overview

CODE REASON EFFECT
Fault Code: 197
PID: P111
SPN: 111
FMI: 1/18
LAMP: Amber
SRT: 

Coolant Level – Data Valid but Below Normal Operational Range – Moderately Severe Level. Low engine coolant level detected.

Power derate and possible engine shut down if the Engine Protection Shutdown feature is enabled.

ISB, ISC, and ISL with CM2150 – Electronic Control Module
SMALL | MEDIUM | LARGE

Circuit Description

The coolant level sensor is a switch and is used to measure the level of the engine coolant in the radiator top tank. The coolant level sensor is immersed in the coolant and returns a different signal voltage when immersed in coolant, versus being out of coolant. The electronic control module (ECM) supplies 5 volts to the coolant level signal circuit. The resistance of the engine coolant level sensor changes, based on the coolant level. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the level of the engine coolant.

Component Location

The engine coolant level sensor is typically located in the radiator top tank or surge tank. Refer to the OEM troubleshooting and repair manual for the location.

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 detects that the coolant level is below the normal operating limit.

Action Taken When the Fault Code is Active

  • The ECM illuminates the amber CHECK ENGINE light after 20 seconds when low engine coolant level has been detected.
  • The torque output of the engine will be reduced.
  • Exhaust gas recirculation (EGR) valve operation will be disabled.

Conditions for Clearing the Fault Code

The ECM will turn off the amber CHECK ENGINE light immediately after 20 seconds of detecting the correct engine coolant level.

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, calibrate the ECM. Refer to Procedure 019-032 in Section 19.

This fault code goes active when the coolant level inside the radiator top tank or surge tank drops below the sensor level. Fill the top tank with coolant.

Refer to Troubleshooting Fault Code t05-197

Last Modified:  20-Jul-2010