P0116

P0116-ENGINE COOLANT TEMPERATURE (ECT) SENSOR RATIONALITY





For complete wiring diagrams refer to Diagrams/Electrical.


- When Monitored:

While the engine is running.

- Set Condition:

The ECM does not read a change in value from the sensor over time.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test


1. LOW COOLANT LEVEL

With the engine cold, verify the level of coolant in the radiator.

Is the radiator full of coolant?

Yes

- Go To 2

No

- Fill the radiator with coolant- refer to the owners manual.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

2. COOLANT TEMPERATURE SENSOR

Remove the temperature sensor and reconnect the wiring to the sensor.

Turn the ignition on.

Monitor scan tool, while heating the sensor with an external heat source (DO NOT USE OPEN FLAME).

Does the reading from the sensor increase at least -15° C (5° F on the scan tool?

Yes

- Go To 3

No

- Replace the coolant temp sensor.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

3. THERMOSTAT

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

Start the engine.

Allow the engine to reach normal operating temperature.

Does the thermostat open properly at the correct temperature?

Yes

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition

No

- Replace the Thermostat.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test