DTC Troubleshooting: P2646 (22)
DTC P2646:
 VTEC System Stuck OFF
Special Tools Required
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 engine oil level OK?
YES -
Go to Step 2 .
NO -
Adjust the engine oil to the proper level, then go to Step 12 .
  1. Turn the ignition switch ON (II).
  1. Clear the DTC with the HDS.
  1. Do the VTEC TEST in the INSPECTION MENU with the HDS.
Is the result OK?
YES -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the EOP sensor, the rocker arm oil control solenoid, and the ECM.■
NO -
Go to Step 5 .
  1. Turn the ignition switch OFF.
  1. Remove the EOP sensor (A), install the special tools as shown, then install the EOP sensor in the oil pressure gauge attachment (B).
    NOTE: Install the parts in the reverse order of removal with a new O-ring.
  1. Start the engine. Hold the engine speed at 3,000 rpm (min −1 ) without load (in neutral) until the radiator fan comes on, then let it idle for 2 minutes.
  1. Do the VTEC TEST in the INSPECTION MENU with the HDS.
  1. Check the oil pressure.
Does the oil pressure increase to at least 30 kPa (0.3 kgf/cm 2 , 4.3 psi)?
YES -
NO -
  1. Turn the ignition switch OFF.
  1. Reconnect all connectors.
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Test-drive under these conditions:
    • Engine coolant temperature (ECT SENSOR 1) above 75 °C (167 °F)
    • Transmission in 3rd gear
    • Engine speed between 1,100−3,300 rpm (min −1 )
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P2646 indicated?
YES -
Check for poor connections or loose terminals at the rocker arm oil control solenoid, the EOP sensor, and the ECM, then go to Step 1 .
NO -
Go to Step 17 .
  1. Monitor the OBD STATUS for DTC P2646 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
Troubleshooting is complete. If any other Temporary DTCs or DTCs were indicated in Step 16 , go to the indicated DTC's troubleshooting.■
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the rocker arm oil control solenoid, the EOP sensor, and the ECM, then go to Step 1 . If the screen indicates NOT COMPLETED, go to Step 15 .