Seville V8-300 4.9L (1991)
Body Control Module: Initial Inspection and Diagnostic Overview
Coolant Temperature Telltale and Chime
Washer Fluid Low Circuit
TEST CONDITION:
1.
Engine is running.
2.
Coolant temperature not failed.
FAILURE CONDITION:
1.
Engine coolant temperature greater than 126°C.
ACTION TAKEN:
Light "Stop - Engine Temp" telltale.
The PCM/ECM provides and internally monitors voltage to the coolant temperature sensor circuit through pin 3E16. As the coolant temperature goes
from cold to hot, the sensor's resistance goes from high to low, and the voltage level the PCM/ECM detects at pin 3E16 goes from high to low. Every 1
second, the BCM checks the PCM/ECM for the coolant temperature. If the calculated coolant temperature reaches 126°C/258°F (i.e., the voltage at pin
3E16 of the PCM/ECM drops low enough), and all other failure conditions are met, the IPC will light the "Stop - Engine Temp" telltale.
Driver Door Ajar
