DTC Troubleshooting: P2648
DTC P2648: Rocker Arm Oil Control Solenoid Circuit Low Voltage
NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description
Confirmed DTC
Pending DTC
P2648 Rocker Arm Oil Control Solenoid Circuit Low Voltage
    

1.
Problem verification:

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.

  

?4.
Check for Pending or Confirmed DTCs with the HDS.
DTC Description
Confirmed DTC
Pending DTC
P2648 Rocker Arm Oil Control Solenoid Circuit Low Voltage
    

Is DTC P2648 indicated?

     
YES
     
     
     
The failure is duplicated. Go to step 2.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the rocker arm oil control solenoid and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot.?
2.
Rocker arm oil control solenoid internal resistance check:

Rocker arm oil control solenoid internal resistance check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
Rocker arm oil control solenoid 2P connector

?3.
At the rocker arm oil control solenoid side, measure the resistance between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Rocker arm oil control solenoid 2P connector: disconnected
Test point 1
Rocker arm oil control solenoid 2P connector No. 1 (rocker arm oil control solenoid side)
Test point 2
Rocker arm oil control solenoid 2P connector No. 2 (rocker arm oil control solenoid side)


Is there 14.6?16.2 ? at room temperature?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
3.
Shorted wire check (VTS line):

Shorted wire check (VTS line)
?1.
Jump the SCS line with the HDS, and wait more than 1 minute.


?2.
Disconnect the following connector.
PCM connector E (80P)

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Rocker arm oil control solenoid 2P connector: disconnected
 
PCM connector E (80P): disconnected
Test point 1
PCM connector E (80P) No. 65
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short in the VTS wire between the PCM (E65) and the rocker arm oil control solenoid.?
     
NO
     
     
     
The VTS wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM, then recheck. If DTC P2648 goes away and the PCM was substituted, replace the original PCM.?