Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC P2647 (KA/Kc)
DTC P2647 : Rocker Arm Oil Pressure Switch Circuit High Voltage
NOTE:
- Before you troubleshoot, review the general troubleshooting information .
- If DTC P2648 and/or P2649 are stored at the same time as DTC P2647, troubleshoot those DTCs first, then recheck for DTC P2647.
| DTC Description | Confirmed DTC | Pending DTC | Freeze Frame |
|---|---|---|---|
| P2647 Rocker Arm Oil Pressure Switch Circuit High Voltage |
DTC (PGM-FI)
- Oil level check
-1. Check the engine oil level .
Is the level OK?
YES
Go to step 2.
NO
- Problem verification
-1. Turn the vehicle to the ON mode.
-2. Clear the DTC with the HDS.
-3. Do the VTEC TEST in the INSPECTION MENU with the HDS.
VTEC TEST
Is the result OK?
YES
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the rocker arm oil pressure switch and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot .
NO
The failure is duplicated. Go to step 3.
- Rocker arm oil pressure switch internal circuit check
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Disconnect the following connector.
Rocker arm oil pressure switch 2P connector -3. At the rocker arm oil pressure switch side, check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Rocker arm oil pressure switch 2P connector: disconnected Test point 1 Rocker arm oil pressure switch 2P connector No. 1 (rocker arm oil pressure switch side) Test point 2 Rocker arm oil pressure switch 2P connector No. 2 (rocker arm oil pressure switch side) Is there continuity?
YES
Go to step 4.
NO
- Open wire check (VTM line)
-1. Jump the SCS line with the HDS.
-2. Disconnect the following connector.
PCM connector C (51P) -3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Rocker arm oil pressure switch 2P connector: disconnected PCM connector C (51P): disconnected Test point 1 Rocker arm oil pressure switch 2P connector No. 2 Test point 2 PCM connector C (51P) No. 48 Is there continuity?
YES
Go to step 5.
NO
Repair an open in the VTM wire between the PCM (C48) and the rocker arm oil pressure switch.
- Open wire check (LG line)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Rocker arm oil pressure switch 2P connector: disconnected PCM connector C (51P): disconnected Test point 1 Rocker arm oil pressure switch 2P connector No. 1 Test point 2 Body ground Is there continuity?
YES
The LG wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P2647 goes away and the PCM was updated, troubleshooting is complete. If DTC P2647 goes away and the PCM was substituted, replace the original PCM .
NO
Repair an open in the LG wire between the rocker arm oil pressure switch and G101.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.