Oil Pressure Warning Light: Early Deactivation?

'On my 1Z engine, the oil pressure warning light only stays on for a fraction of a second and then goes out before the engine even starts. The LED must be working fine. Does anyone have any ideas?'

Best regards, T3.

Hi T3 ,
Did you measure the switch?
If the LED is not directly connected to the switch, it may briefly light up (perhaps for a self-test) when the switch is turned on, and then turn off as soon as the oil pressure switch closes.
If there's a short circuit now, it should immediately turn off again.