DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P2649

DTC P2649 : Rocker Arm Oil Control Solenoid Circuit High Voltage

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How To Troubleshoot The Fuel And Emissions Systems.

1. Problem verification:

Problem verification
-1. Turn the ignition switch to ON (II).

-2. Clear the DTC with the HDS.

-3. Start the engine. Hold the engine speed at 3,000 rpm without load (in neutral) until the radiator fan comes on, then let it idle.

-4. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P2649 indicated?
-YES- 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 pressure switch, the rocker arm oil control solenoid, and the ECM.

2. Rocker arm oil control solenoid internal resistance check:

Rocker arm oil control solenoid internal resistance check
-1. Turn the ignition switch to LOCK (0).

-2. Disconnect the following connector.





-3. At the rocker arm oil control solenoid side, check for continuity between test points 1 and 2.









Is there 14-30 Ohms at room temperature?
-YES- Go to step 3.
-NO- Replace the rocker arm oil control valve Rocker Arm Oil Control Valve Removal and Installation, then do the repair verification.

3. Open wire check (PG1 line):

Open wire check (PG1 line):
-1. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- Go to step 4.
-NO- Repair an open in the PG1 wire between the rocker arm oil control solenoid and the G101, then do the repair verification.

4. Shorted wire check (VT_SOL_IN line):

Shorted wire check (VT_SOL_IN line)
-1. Jump the SCS line with the HDS.

-2. Disconnect the following connector.





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









Is there continuity?
-YES- The VT_SOL_IN wire is OK. Update the ECM ECM/PCM Update if it does not have the latest software, or substitute a known-good ECM Service and Repair, then do the repair verification.
-NO- Repair an open in the VT_SOL_IN wire between the rocker arm oil control solenoid and the ECM (B33), then do the repair verification.

Repair verification:

-1. Reconnect all connectors.

-2. Turn the ignition switch to ON (II).

-3. Reset the ECM with the HDS How To Troubleshoot The Fuel And Emissions Systems.

-4. Do the ECM idle learn procedure ECM/PCM Idle Learn Procedure.

-5. Start the engine. Hold the engine speed at 3,000 rpm without load (in neutral) until the radiator fan comes on, then let it idle

-6. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P2649 indicated?
-YES- Check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid, and the ECM. If the ECM was updated, substitute a known-good ECM Service and Repair, then recheck. If the ECM was substituted, go to step 1.
-NO- Troubleshooting is complete. If the ECM was substituted, replace the original ECM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.