DTC Troubleshooting: P2646 (22)

DTC P2646:  Rocker Arm Oil Pressure Switch Circuit Low Voltage

Special Tools Required
Oil pressure gauge attachment (  07NAJ-P070100)
 

Low pressure gauge (  07406-0070002)
 
Oil pressure hose (  07ZAJ-S5A0200)
 


NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

1.Check the engine oil level.

Is the level OK?


YES - Go to 2.


NO - Adjust the engine oil to the proper level, then go to 19.


2.Turn the ignition switch ON (II).

3.Clear the DTC with the HDS.

4.Do the VTEC TEST in the INSPECTION MENU with the HDS.

Is the result OK?


YES - Intermittent failure, 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/PCM.n


NO - Go to 5.


5.Turn the ignition switch OFF.

6.Disconnect the rocker arm oil pressure switch 2P connector.

7.Turn the ignition switch ON (II).

8.Check the VTEC PRES SW in the DATA LIST with the HDS.

Is SWITCH ON indicated?


YES - Go to 15.


NO - Go to 9.

9.Turn the ignition switch OFF.

10.Remove the rocker arm oil pressure switch (A), and install the special tools as shown, then install the rocker arm oil pressure switch in the oil pressure gauge attachment (B).

NOTE: Install the switch in the reverse order of removal with a new O-ring.

 

11.Reconnect the rocker arm oil pressure switch 2P connector.

12.Start the engine.

13.Do the VTEC TEST in the INSPECTION MENU with the HDS.

14.Check the oil pressure.

Does the oil pressure increase to at least 392 kPa(4.0 kgf/cm2 , 56.9 psi)?


YES - Replace the rocker arm oil pressure switch, then go to 18.


NO - Inspect the VTEC system. If it is OK. replace the rocker arm oil control solenoid, then go to 18.

15.Turn the ignition switch OFF.

16.Disconnect ECM/PCM connector C (44P).

17.Check for continuity between ECM/PCM connector terminal C22 and body ground.

 

Is there continuity?


YES - Repair short in the wire between the ECM/PCM (C22) and the rocker arm oil pressure switch, then go to 18.


NO - Go to 25.


18.Reconnect all connectors.

19.Turn the ignition switch ON (II).

20.Reset the ECM/PCM with the HDS.

21.Do the ECM/PCM idle learn procedure.

22.Do the VTEC TEST in the INSPECTION MENU with the HDS.

23.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P2646 is indicated, check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid and the ECM/PCM, then go 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - Troubleshooting is complete.n


24.Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM.

25.Do the VTEC TEST in the INSPECTION MENU with the HDS.

26.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P2646 is indicated, check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM.n