The fluid of the CVVT is the engine oil and its density changes according to the engine oil temperature. At this time the Oil Temperature Sensor (OTS) helps compensation against the temperature differences. The Oil Temperature Sensor measures the engine oil temperature before the engine oil comes into the Oil-flow Control Valve (OCV).According to the measured temperature, the Engine Control Module (ECM) compensates the oil-flow control valve operation time.
ECM sets DTC P0197 if the ECM detects signal voltage lower than the possible range of a properly operating OTS.
Item
Detecting Condition
Possible Cause
DTC Strategy
? Engine coolant temperature
? Short circuit to ground
? Contact resistance in connectors
? Faulty OTS
Enable Conditions
? Engine coolant temperature < 100?(212?)
? No relevant failure
? 6 < Battery voltage
Threshold Value
? Oil temperature > 154?(309?)
Diagnostic Time
? 5 seconds
MIL On Condition
? 2 Driving Cycles
Temp.(°C)
Temp.(°F)
OTS Resistance(k?)
-20
-4
Approx. 14.1~16.9
40
104
Approx. 1.1~1.2
0
32
Approx. 6
60
140
Approx. 0.5~0.6
20
68
Approx. 2.3~2.6
80
176
Approx. 0.3