What Causes the Oil Pump Light to Illuminate?
2 Answers
The reasons for the oil pump light to illuminate are as follows: 1. The pressure relief valve is clogged or improperly adjusted. To prevent excessive oil pressure in the lubrication system, which increases engine power consumption and causes oil leaks at sealed connections, a pressure relief valve is installed in the main oil passage or oil pump. A malfunctioning pressure relief valve can lead to abnormal oil pressure, causing the oil light to illuminate. 2. Insufficient oil level. If the oil level is too low, the oil pump's output decreases or fails to pump oil due to air ingress, resulting in a drop in oil pressure and the illumination of the oil light. 3. Engine overheating. An overheated engine accelerates the aging, degradation, and thinning of the oil, causing it to leak through various clearances, reducing pressure and triggering the oil warning light. 4. Clogged oil filter. When the oil filter is blocked and cannot circulate oil, the bypass valve on its base opens, allowing oil to bypass the filter and enter the main oil passage directly. If the bypass valve's opening pressure is set too high or too low, the oil pump's pressure will rise or fall, leading to the light illuminating.
When the oil light comes on, my first reaction is to pull over immediately and check—this is no small matter. Common causes could be low oil levels, either because the engine is burning oil too aggressively or there's a leak in the oil pan, where oil slowly seeps out, reducing the total volume. If the oil pump fails—due to internal part wear or a clogged filter screen—it can't circulate oil properly, leading to a drop in pressure and triggering the light. Another possibility is a faulty oil pressure sensor sending inaccurate warnings. Last time my light came on, I pulled over, checked the dipstick, and sure enough, the level was low—topping it off with fresh oil fixed the issue. But if you keep driving with the light on, increased engine friction can lead to overheating or even total engine failure, resulting in costly repairs. So, my advice is to pull over, shut off the engine, check the oil level, and top it off if needed. If that doesn’t help, head to a professional shop to test the pump and sensor. To prevent this, make it a habit to check oil levels and change the oil every few thousand kilometers—better safe than sorry.
