Oil Pressure Indicator

WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 2005 Acura NSX, 2004 Acura NSX, 2003 Acura NSX-T, 2003 Acura NSX, and 2002 Acura NSX-T. However, it is still accessible from the selected car via links, so may be relevant.

The oil pressure warning indicator light works in two ways: it flashes continuously following a momentary loss of oil pressure, or it goes on and stays on with a complete loss of oil pressure. When the ignition switch is in RUN or START, battery voltage is applied to the oil pressure warning light. If the engine is not started, the closed oil pressure switch provides a ground and the light goes on.

When the engine is started, the alternator provides an engine running input to the integrated control unit. With normal oil pressure, the oil pressure switch is open and the oil pressure warning indicator light does not go on. If the oil pressure closes momentarily (more than 0.5 seconds) but then opens again, the YEL/RED wire at the integrated control unit will sense ground through the switch. The integrated control unit will then provide and remove ground for the oil pressure warning indicator light through the YEL/RED wire. The light will flash on and off until the ignition switch is cycled to OFF. The flashing feature will not work until 30 seconds after the engine running input is supplied by the alternator. This delay avoids unnecessary warning light operation.

If engine oil pressure falls below 4.3 psi and does not increase while the engine is running, the oil pressure switch will stay closed. The oil pressure warning indicator light will go on and stay on.