DTC Troubleshooting: P2646 (22)
  1. Check for continuity between ECM connector terminal C22 and body ground.
Is there continuity?
YES -
Repair short in the wire between the ECM (C22) and the rocker arm oil pressure switch, then go to Step 19 .
NO -
Go to Step 26 .
  1. Reconnect all connectors.
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Do the ECM idle learn procedure.
  1. Do the VTEC TEST in the INSPECTION MENU with the HDS.
  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 pressure switch, the rocker arm oil control solenoid and the ECM, then go Step 1 .
NO -
Go to Step 25 .
  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 24 , go to the indicated DTC's troubleshooting.■
NO -
If the screen indicates FAILED, go to Step 1 and recheck. If the screen indicates NOT COMPLETED, go to Step 23 and recheck.
  1. Reconnect all connectors.
  1. Update the ECM if it does not have the latest software, or substitute a known-good ECM.
  1. Do the VTEC TEST in the INSPECTION MENU with the HDS.
  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 pressure switch, the rocker arm oil control solenoid, and the ECM. If the ECM was updated, substitute a known-good ECM, then go to Step 28 . If the ECM was substituted, go to Step 1 .
NO -
Go to Step 30 .
  1. Monitor the OBD STATUS for DTC P2646 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. If any other Temporary DTCs or DTCs were indicated in Step 29 , 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 pressure switch, the rocker arm oil control solenoid, and the ECM. If the ECM was updated, substitute a known-good ECM, then go to Step 28 . If the ECM was substituted, go to Step 1 . If the screen indicates NOT COMPLETED, go to Step 28 and recheck.