DTC P2648

DTC P2648  : Rocker Arm Oil Control Solenoid A (Bank 1) Circuit Low Voltage

DTC (PGM-FI)

1. Problem verification

   -1. Turn the vehicle to the ON mode.

   - 2. Clear the DTC with the HDS.

   - 3. Select the VTEC+VCM TEST in the INSPECTION MENU, then select the SOLENOID B of the SOL.V.ACTIVATION with the HDS.

   SOL.V.ACTIVATION

   Check for Pending or Confirmed DTCs with the HDS.

   DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
   P2648 Rocker Arm Oil Control Solenoid A (Bank 1) 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 rocker arm oil control solenoid A (Bank 1) 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.

2. Rocker arm oil control solenoid A (Bank 1) internal resistance check

   -1. Turn the vehicle to the OFF (LOCK) mode.

   - 2. Disconnect the following connector.

   Rocker arm oil control solenoid A (Bank 1) 2P connector - Refer to: Front Rocker Arm Oil Control Valve Removal and Installation, or Rear Rocker Arm Oil Control Valve Removal and Installation

   - 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 A (Bank 1) 2P connector: disconnected
   Test circuit	VTSB1, VTSB1 PG
   Test point 1	Rocker arm oil control solenoid A (Bank 1) 2P connector No. 1 (rocker arm oil control solenoid side)
   Test point 2	Rocker arm oil control solenoid A (Bank 1) 2P connector No. 2 (rocker arm oil control solenoid side)

   Courtesy of HONDA, U.S.A., INC.

   Is there 14-30 Ω at room temperature?

   YES 

   Go to step 3.

   NO 

   Replace the rear rocker arm oil control valve (rocker arm oil control solenoid A (Bank 1)) - Refer to: Front Rocker Arm Oil Control Valve Removal and Installation, or Rear Rocker Arm Oil Control Valve Removal and Installation .

3. Shorted wire check (VTSB1 line)

   -1. Jump the SCS line with the HDS.

   - 2. Disconnect the following connector.

   PCM connector C (51P) - Refer to: How to Troubleshoot the Fuel and Emissions Systems, or How to Troubleshoot the Brake Booster Pressure Monitoring System (2016 2017 2018 2019 2020), or How to Troubleshoot the Fuel and Emissions Systems(With Auto Idle Stop System) (2016), or How to Troubleshoot the A/T System (2014 2015)

   - 3. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Rocker arm oil control solenoid A (Bank 1) 2P connector: disconnected
   	PCM connector C (51P): disconnected
   Test circuit	VTSB1
   Test point 1	PCM connector C (51P) No. 15 (LT GRN)
   Test point 2	Body ground

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   Repair a short in the VTSB1 wire between rocker arm oil control solenoid A (Bank 1) and the PCM (C15).

   NO 

   The VTSB1 wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM - Refer to: PCM Removal and Installation (2014 2015), or PCM Removal and Installation (2016) .