CM871 and CM876 Electronic Control Systems, ISX and ISM Engines – FAULT CODE 195 (3-Wire Sensor)

Coolant Level Sensor 1 Circuit – Voltage Above Normal, or Shorted to High Source


Overview

CODE REASON EFFECT
Fault Code: 195
PID: P111
SPN: 111
FMI: 3/3
LAMP: Amber
SRT: 

Coolant Level Sensor 1 Circuit – Voltage Above Normal, or Shorted to High Source. High signal voltage detected at engine coolant level circuit.

None on performance.

ISX and ISM – Engine Coolant Level Sensor 1 Circuit
SMALL | MEDIUM | LARGE

Circuit Description

The electronic control module (ECM) supplies a 5 volt supply to the engine coolant level sensor using a common sensor supply circuit. The ECM also provides a ground on the sensor return circuit. The engine coolant level sensor provides a signal to the ECM on the engine coolant level sensor signal circuit. This sensor signal voltage changes based on the coolant level in the expansion tank.

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 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 signal voltage is greater than 4.5-VDC for more than 1 second.

Action Taken When the Fault Code is Active

  • The ECM illuminates the amber CHECK ENGINE light immediately when the diagnostic runs and fails.
  • No engine protection will be available for low coolant level.

Conditions for Clearing the Fault Code

The ECM will turn off the amber CHECK ENGINE light immediately after 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.

Possible causes of this fault code include:

  • Open return circuit in the engine harness, connectors, or sensor.
  • Signal circuit shorted to sensor supply or battery voltage.
  • Sensor supply circuit shorted to battery voltage.

Refer to Troubleshooting Fault Code t05-195

Last Modified:  09-Jul-2010