Generally, when the oil pressure light comes on, next to checking the oil level, changing the sensor is the next step since they are cheap anyway and usually fix it. If you have the 3.3 or 3.8 ltr engine it's located to the left of the oil filter. Verify the connection is in good shape then use a wrench to remove. May have to remove the oil filter first. If you're still having problems after changing it connect a direct pressure gauge to verify what pressure in there.
Sensor/sender same same. If you haven't changed the oil lately you might consider it. Low idle rpm good be the culprit. How's that look?
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96 Gr Caravan LE 3.8, 212K miles
07 Fusion / 06 RAV 4 / 06 Accord