GM Service Manual Online
For 1990-2009 cars only

The coolant temperature telltale on the instrument panel (I/P) cluster has the ability to illuminate as a result of an engine over temperature condition. The engine control module (ECM) or powertrain control module (PCM) will send a message to the I/P cluster over the class 2 link to turn the coolant temperature telltale ON if the engine coolant temperature (ECT) exceeds the temperature calibration value listed under Conditions for Setting the DTC.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

    • The engine coolant temperature (ECT) is greater than 117°C (242°F).
    • No other ECT sensor DTCs have been set.
    • The ECM/PCM will command the A/C relay OFF if the temperature of the engine coolant is greater than 117°C (242°F).

DTC P0217 diagnostic runs continuously once the above conditions have been met.

Conditions for Clearing the MIL/DTC

    • The ECM/PCM will turn the malfunction indicator lamp (MIL) OFF after 3 consecutive trips that the diagnostic has been run and passed.
    • The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
    • The DTC can be cleared by using the scan tool.

Diagnostic Aids

    • Cooling fan inoperative -- Refer to Cooling Fan Inoperative .
    • Engine cooling system overheated condition (thermostat, low engine coolant etc.) -- Refer to Engine Overheating .
    • Radiator or condenser air flow restricted
    • Air dam missing or loose
    • Overload due to trailer towing
    • ECT sensor leaking engine coolant into ECT sensor harness connector causing elevated temperatures
    • ECT sensor skewed

Step

Action

Yes

No

Schematic Reference: Engine Cooling Schematics

Connector End View Reference: Cooling System Connector End Views

1

Did you perform the Engine Cooling Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Engine Cooling

2

Check the engine cooling fans for proper operation.

Are the engine cooling fans operative?

Go to Engine Overheating

Go to Symptoms - Engine Cooling