P0116
DTC P0116
CIRCUIT DESCRIPTION
An engine coolant temperature (ECT) sensor monitors the temperature of the coolant. This input is used by the engine control module (ECM) for engine control and as an enabling criteria for other diagnostics.
The purpose of this ECT sensor performance diagnostic is to detect an ECT sensor that is stuck in range. This diagnostic will detect a fixed ECT signal throughout the complete range of the sensor.
Using this diagnostic the ECM calculates the following:
- The delta or change in the actual engine coolant temperature from start-up ECT
- The delta or change in the modeled engine coolant temperature from start-up ECT
When the delta of the modeled ECT reaches a calibrateable value it is compared to the delta of the actual ECT.
If the ECM detects that the actual change in the measured ECT is less than the change in the modeled ECT, DTC P0116 sets.
DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC P0116 Engine Coolant Temperature (ECT) Sensor Performance
CONDITIONS FOR RUNNING THE DTC
- DTCs P0101, P0102, P0103, P0112, P0113, P0117, P0118 are not set.
- The engine is running.
- Engine metal over-temperature protection (EMOP) is not active
- This diagnostic will run once and complete during all driving conditions.
CONDITIONS FOR SETTING THE DTC
If the ECM detects that the actual change in the measured ECT is less than the change in the modeled ECT, DTC P0116 sets.
ACTION TAKEN WHEN THE DTC SETS
- The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
- The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.
CONDITIONS FOR CLEARING THE MIL/DTC
- The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
- A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
- Clear the MIL and the DTC with a scan tool.
TEST
