The most common problem that can set the P2652 code is the engine oil. Before replacing any parts change the engine oil with the factory recommend oil weight.
There is a Factory Service Bulletin for the following Honda Models
2003-2012 Honda Accord L4
2002-2005 Honda Civic Si
2002-2009 Honda CR-V
2011 Honda CR-Z
2003-2011 Honda Element
2007-2011 Honda Fit
The factory bulletin suggests that replacing the VTEC oil pressure switch (P/N 37250-PNE-G01, H/C 6737217) take care of the problem.
Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
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What is the Cost to Diagnose the Code?
Labor: 1.0
The cost to diagnose the P2647 Honda code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.
What are Code Possible Symptoms?
Engine Light ON (or Service Engine Soon Warning Light)
What Does the P2647 Honda Code Mean?
The VTEC system activates the rocker arm oil control solenoid (VTEC solenoid valve) by command from the Engine Control Module (ECM)/Powertrain Control Module (PCM), and it charges/discharges the hydraulic circuit of the VTEC mechanism that switches valve timing between Low and High. The ECM/PCM monitors oil pressure in the hydraulic circuit of the VTEC mechanism using the rocker arm oil pressure switch (VTEC oil pressure switch) downstream of the rocker arm oil control solenoid (VTEC solenoid valve). If there is a difference between the oil pressure condition in the hydraulic circuit that is determined by the ECM/PCM command and the oil pressure condition that is determined by the status of the rocker arm oil pressure switch (VTEC oil pressure switch), the system is considered faulty, and a DTC is stored.
P2647 Honda Code - Rocker Arm Oil Pressure Switch Circuit High Voltage