DTC 14

Fig. 022 Chart - Code 14 Coolant Sensor Circuit (Signal Voltage Low):

Fig. 025 - WIRING DIAGRAM for Code 14 Coolant Sensor Circuit (Signal Voltage Low). VIN L:

CODE 14

COOLANT SENSOR (SIGNAL VOLTAGE LOW)

3.0L "N" SERIES

FUEL INJECTION (PORT)

The Coolant Temperature Sensor uses a thermistor to control the signal voltage to the ECM. The ECM applies a voltage on CKT 410 to the sensor. When the engine is cold the sensor (thermistor) resistance is high, therefore the ECM will see high signal voltage.
As the engine warms, the sensor resistance becomes less, and the voltage drops. At normal engine operating temperature the voltage will measure about 1 to 1.5 volts at the ECM terminal C10.
Coolant temperature is one of the inputs used to control:
a. Fuel delivery.
b. Engine Spark Timing (EST)
c. Knock Control (ESC)
d. Idle (IAC)
e. Convertor Clutch (TCC)
f. Canister Purge (CCP)
g. EGR
Code 14 will set if signal voltage indicates a coolant temperature above 140°C (285°F) for 4 seconds.
1. Checks to see if code was set as result of hard failure or intermittent condition.
2. If voltage is above 4 volts, the ECM and wiring are OK.