Good Day Experts, Need your help

I encountered intermittent engine oil indicator blinking this morning. Actually I'm not sure if this is engine oil indicator, but this could be found on the RPM panel on dashboard. This is on the left side of the battery indicator. I called Joseph A22BO and told me that this is engine oil indicator and the blinking could be due to low level engine oil. So I inspect the oil dipstick and found that this is on low side indeed, so I replenish the engine then run. After a while the blinking again showed up. I don't bother joseph anymore as he drove to UST. Anyway, I re-inspect the oil and its on the same level since I topped it up but intermittent blinking is really evident. I pulled over to EDSA Hyundai Service Center near crame and talked to Quality Control Mechnanic and told me that my car is safe to drive and the blinking is due to either damage sending unit or some electrical fault on my sending unit. So I drive up to Alabang (my office).

Last thing that I noticed is that when I restart the car this indicator doesn't light up while most indicators turned on.

My ride is Pajero 2.8 AT field master. Sorry for asking, I don't have the user manual as I'm the 2nd owner. What are your opinion here? Any idea on the cost of sending unit? Thanks in advance. Thanks to A22BO too.

Regards,
Cesar