Stop Engine Temp Telltale and Engine Coolant Hot

Coolant Temperature Sensor Circuit:

CIRCUIT DESCRIPTION:
The PCM provides and internally monitors voltage to the coolant temperature sensor circuit through pin "1B5." As the coolant temperature goes from cold to hot, the sensor's resistance goes from high to low, and the voltage level the PCM detects at pin "1B5" goes from high to low. Every 1 second, the BCM checks the PCM for the coolant temperature. If the calculated coolant temperature reaches 126 degrees centigrade (i.e. the voltage at pin "1B5" of the PCM drops low enough), and all other failure conditions are met, the IPC will light the "STOP - ENGINE TEMP" telltale and the CCDIC will display the message "ENGINE COOLANT HOT." The code will be stored as history when the coolant temperature drops below 121°C. The code will be stored as history when the coolant temperature drops below 121°C.

TEST CONDITION(S):
1.Engine is running.

FAILURE CONDITION(S):
1. Engine coolant temperature greater than 125 degrees centigrade.

ACTION TAKEN:
1. Light "STOP - ENGINE TEMP" telltale.
2. Display the "ENGINE COOLANT HOT" message on the CCDIC.