E014

Code E014 - Coolant Temp. Sensor (High Temp. Indicated):

Temperature To Resistance Values:

Wiring Diagram for Code EO14 - Coolant Temp. Sensor (High Temp. Indicated):

CODE E014 - COOLANT TEMPERATURE SENSOR (HIGH TEMPERATURE INDICATED)

Circuit Description:

The Coolant Temperature Sensor is a thermistor that changes resistance as it's temperature changes. When the engine is cold, the resistance of the sensor is high, as the engine warms, the resistance of the sensor decreases.

The ECM applies 5 volts to terminal "C10". When the engine is cold, (resistance high), the ECM will monitor a high voltage at "C10". As the engine warms, (resistance decreases), the voltage at "C10" will decrease. At normal engine operating, temperature,the ECM will monitor from 1 to 1.5 volts at terminal "C10". Coolant temperature is one of the inputs used to calculate:

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 E014 will set if:

a. Coolant temperature is above 140°C (285°F).
b. Engine run time is longer than 20 seconds.




Test Description: The following numbered steps correspond with the step numbers on the diagnostic chart.

1. Verify that a problem exists. If no problems exist, check for loose connections. Engine must be at normal operating temperature for reliable diagnosis. Make sure engine cooling system is functioning properly and engine is not overheating.

2. Disconnect coolant sensor. Display going to -30° or colder indicates that coolant sensor was the source of the problem. If display does not change CKT 410 has a possible short to ground or the ECM is malfunctioning.




Diagnostic Aids:

An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside the insulation.

Check For:

a. Poor Connection or Damaged Harness - Inspect ECM harness connectors for backed out terminals "C10" or "D12", improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection and damaged harness.

b. Intermittent Test - If connections and harness checks out ok, monitor ED04 (Coolant Temperature) display while moving related connectors and wiring harness. If the failure is induced, the "Coolant Temperature" display will abruptly change. This will help to isolate the location of the malfunction.



c. Shifted Sensor - The "Temperature To Resistance Value" scale above may be used to test the coolant sensor at various temperature levels to evaluate the possibility of a "shifted" (mis-scaled) sensor which may result in dirveability complaints.