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 (PCM) compensates the oil-flow control valve operation time.
PCM sets DTC P0197 if the PCM detects signal voltage lower than the possible range of a properly operating OTS.
ITEM | DETECTING CONDITION | POSSIBLE CAUSE |
DTC Strategy | ● Voltage range check | ● Short circuit to ground ● Contact resistance in connectors ● Faulty OTS |
Enable Condition | ● Engine coolant temperature ＜ 100°C(212°F) | |
Threshold Value | ● Oil temperature > 154°C(309°F) | |
Diagnostic Time | ● 5 seconds |
Temp.(°C) | Temp.(°F) | Resistance(kΩ) | Temp.(°C) | Temp.(°F) | Resistance(kΩ) |
-20 | -4 | 16.52 | 40 | 104 | 1.11 |
0 | 32 | 6.00 | 60 | 140 | 0.54 |
20 | 68 | 2.45 | 80 | 176 | 0.29 |
