This bulletin applies to 2007-2012 Acura RDX and 2002-2006 RSX models. The MIL may be on with one of the following DTCs:
P2646 (rocker arm oil pressure switch circuit low voltage)
P2647 (rocker arm oil pressure switch circuit high voltage)
The symptom may be intermittent and you may not be able to duplicate it after clearing the DTC. The possible cause is an intermittently failing rocker arm oil pressure switch. Replace the rocker arm oil pressure switch with P/N 37250-PNE-G01 along with O-ring 91319-PAA-A01.
Remove the power steering high pressure hose bracket mounted on the valve cover. Remove the rocker arm oil pressure switch and the O-ring. Install the new switch and O-ring and torque the pressure switch to 16 ft.-lbs. Reinstall the power steering hose bracket. Clear the code and verify.