GM Service Manual Online
For 1990-2009 cars only

The coolant temperature telltale on the instrument panel (I/P) has the ability to illuminate as a result of an engine over-temperature condition. The PCM will send a message to the I/P cluster over the Class II link to turn the coolant temperature telltale ON if the engine coolant temperature (ECT) exceeds the temperature calibration value listed under DTC parameters. The coolant temperature gage will read approximately 7/8 of the way toward HOT when the telltale is turned ON.

Conditions for Setting the DTC

DTC P0217 will set if the following conditions occur:

    • The engine coolant temperature (ECT) is greater than 118°C (244°F).
    • No other ECT sensor DTCs have been set.

DTC P0217 diagnostics run continuously once the above conditions have been met.

DTC P0217 is a type D DTC.

Diagnostic Aids

Possible causes of DTC P0217:

    • Cooling fans inoperative
    • Engine cooling system overheated condition - thermostat, low engine coolant etc.
    • 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

Refer to ECT Sensor General Description for a Temperature vs. Resistance chart.

The PCM will command the A/C relay OFF if the temperature of the engine coolant is greater than 120°C (248°F) to protect the engine and transaxle.