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2010 Honda accord ex 2.4 ivtec P2647 oil pressure switch a circuit high voltage vtec system stuck on
Diagnosing a car and looking at info for the circuit involved is giving me conflicting information. Specifically voltage for circuit one says 5 volts another says 12 volts. I read 12 volts key on engine off connector at switch disconnected. However it won't light a test light (regular incandescent style). I have tested ground and it supports a headlight bulbs current. But power feed from ECM wont light anything but a led light. I have not tested the harness feed side wiring just yet I just need to know what it should be for voltage and if its a current limited circuit.
You're talking about the VTEC solenoid, or pressure switch? SI says the pressure switch should have "about 5V":
For the solenoid, I couldn't find anything in SI that says one way or the other what's supposed to be on the control circuit. They just have you doing resistance testing a substituting a known good PCM if all else fails. A 'soft' 12V like what you're seeing sure sounds like a bias voltage to me.
I have seen the tsm for it along with the one for rattle sound on cold startup (another issue it has actuator bolted to camshaft issue) though that one has nothing mentioned on a code for p2647).
VTEC switches and body and filter are new as well as solenoids.