DTC Advanced Diagnostics: P2184, P2185
DTC P2184:Engine coolant temperature (ECT) Sensor 2 Circuit Low Voltage
DTC P2185:Engine coolant temperature ECT Sensor 2 Circuit High Voltage

General Description


Engine coolant temperature (ECT) sensor 2 is a thermistor attached to the radiator. The powertrain control module (PCM) applies voltage (about 5 V) to the TW2 signal circuit through a pull-up resistor. As the engine coolant temperature cools, ECT sensor 2 resistance increases, and the PCM detects a high signal voltage. As the engine coolant warms, the sensor resistance decreases, and the PCM detects a low signal voltage. If the ECT sensor 2 output voltage is a set value when the engine coolant temperature is high or low, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Continuous
Sequence
None
Duration
2 seconds or more
DTC Type
Two drive cycles, MIL on

Enable Conditions
Condition
 
Vehicle
ON mode

Malfunction Threshold
DTC: P2184

The ECT sensor 2 output voltage [ECT SENSOR 2] is 0.08 V or less for at least 2 seconds.

DTC: P2185

The ECT sensor 2 output voltage [ECT SENSOR 2] is 4.92 V or more for at least 2 seconds.

[ ]: HDS Parameter

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
DTC: P2184
ECT sensor 2 TW2/TW2 SENSOR line short to ground

DTC: P2185
ECT sensor 2 TW2/TW2 SENSOR line open
ECT sensor 2 SG6 line open

Common
ECT sensor 2 failure
PCM internal circuit failure

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.