Vtec Acura TL IV

Scheme 106

DTC P2646: Rocker Arm Oil Pressure Switch Circuit Low Voltage

Special Tools Required

1. Pressure gauge adapter 07NAJ-P07010A
2. A/T low pressure gauge w/panel 07406-0070301
3. A/T pressure Test Hose 07AAJ-PY4A100
4. A/T pressure adapter 07MAJ-PY40120
5. Oil pressure hose 07ZAJ-S5AA200

Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 107

Scheme 108

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 19
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
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, 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 PCM NO -Go to step 5
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect the rocker arm oil pressure switch 2P connector
7. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
8. Check the VTEC PRES SW in the DATA LIST with the HDS Is switch ON indicated? YES -Go to step 14 NO -Go to step 9
9. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
10. Remove the rocker arm oil pressure switch (A), attach the special tools as shown, then attach the rocker arm oil pressure switch to the oil pressure gauge adapter (B)
11. Start the engine
12. Do the VTEC TEST in the INSPECTION MENU with the HDS
13. Check the oil pressure Does the oil pressure increase to at least 392 kPa (4 0 kgf/cm 2 , 56 9 psi)? YES -Replace the rocker arm oil pressure switch (see «ROCKER ARM OIL CONTROL SOLENOID REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#vtec) ), then go to step 18 NO -Inspect the VTEC system If it is OK, replace the rocker arm oil control solenoid (see «ROCKER ARM OIL CONTROL SOLENOID REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#vtec) ), then go to step 18
14. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
15. Jump the SCS line with the HDS
16. Disconnect PCM connector B (49P)
17. Check for continuity between PCM connector terminal B20 and body ground Is there continuity? YES -Repair short in the wire between the PCM (B20) and the rocker arm oil pressure switch, then go to step 18 NO -Go to step 24
18. Reconnect all connectors
19. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
20. Reset the PCM with the HDS
21. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#idle-control-system__pcm-idle-learn-procedure) )
22. Do the VTEC TEST in the INSPECTION MENU with the HDS
23. Check for Pending or Confirmed DTCs with the HDS Is DTC P2646 indicated? YES -Check for poor connections or loose terminals at the rocker arm oil pressure switch and the PCM, then go to step 1 NO -Troubleshooting is complete If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting
24. Reconnect all connectors
25. Update the PCM if it does not have the latest software (see «ECM/PCM UPDATE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) )
26. Do the VTEC TEST in the INSPECTION MENU with the HDS
27. Check for Pending or Confirmed DTCs with the HDS Is DTC P2646 indicated? YES -Check for poor connections or loose terminals at the rocker arm oil pressure switch and the PCM If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then go to step 26 If the PCM was substituted, go to step 1 NO -If the PCM was updated, troubleshooting is complete If the PCM was substituted, replace the original PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-replacement) ) If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting

DTC P2647: Rocker Arm Oil Pressure Switch Circuit High Voltage

Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 109

Scheme 110

Scheme 111

1. Check the engine oil level Is the engine oil level OK? YES -Go to step 2 NO -Adjust the engine oil level, then go to step 17
2. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
3. Clear the DTC with the HDS
4. Check the rocker arm oil pressure switch in the DATA LIST with the HDS Does the screen indicate OFF? YES -Go to step 5 NO -Intermittent failure, the system is OK at this time Check for poor connections or loose terminals at the rocker arm oil pressure switch and the PCM
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect the rocker arm oil pressure switch 2P connector
7. Connect rocker arm oil pressure switch 2P connector terminals No 1 and No 2 with a jumper wire
8. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
9. Check the rocker arm oil pressure switch in the DATA LIST with the HDS Does the screen indicate ON? YES -Replace the rocker arm oil pressure switch (see «ROCKER ARM OIL CONTROL SOLENOID REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#vtec) ), then go to step 16 NO -Go to step 10
10. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
11. Remove the jumper wire from the rocker arm oil pressure switch
12. Jump the SCS line with the HDS
13. Disconnect PCM connector B (49P)
14. Check for continuity between PCM connector terminal B20 and locker arm oil pressure switch 2P connector terminal No 1 Is there continuity? YES -Go to step 15 NO -Repair open in the wire between the PCM (B20) and the rocker arm oil pressure switch, then go to step 16
15. Check for continuity between the rocker arm oil pressure switch 2P connector terminal No 2 and body ground Is there continuity? YES -Go to step 22 NO -Repair open in the wire between the rocker arm oil pressure switch and G101, then go to step 16
16. Reconnect all connectors
17. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
18. Reset the PCM with the HDS
19. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#idle-control-system__pcm-idle-learn-procedure) )
20. Check for Pending or Confirmed DTCs with the HDS Is DTC P2647 indicated? YES -Check for poor connections or loose terminals at the rocker arm oil pressure switch and the PCM, then go to step 1 NO -Go to step 21
21. Monitor the OBD STATUS for DTC P2647 in the DTCs MENU with the HDS Does the screen indicate PASSED? YES -Troubleshooting is complete If any other Pending or Confirmed DTCs were indicated in step 20, 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 and the PCM, then go to step 1 If the screen indicates NOT COMPLETED, keep idling until a result comes on
22. Reconnect all connectors
23. Update the PCM if it does not have the latest software (see «ECM/PCM UPDATE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) )
24. Start the engine, and let it idle
25. Check for Pending or Confirmed DTCs with the HDS Is DTC P2647 indicated? YES -Check for poor connections or loose terminals at the rocker arm oil pressure switch, the rocker arm oil control solenoid, and the PCM If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then go to step 24 If the PCM was substituted, go to step 1 NO -Go to step 26
26. Monitor the OBD STATUS for DTC P2647 in the DTCs MENU with the HDS Does the screen indicate PASSED? YES -If the PCM was updated, troubleshooting is complete If the PCM was substituted, replace the original PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-replacement) ) If any other Pending or Confirmed DTCs were indicated in step 25, 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 and the PCM If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then go to step 24 If the PCM was substituted, go to step 1 If the screen indicates NOT COMPLETED, keep idling until a result comes on

DTC P2648: Rocker Arm Oil Control Solenoid Circuit Low Voltage

Note. Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 112

Scheme 113

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. 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 rocker arm oil control solenoid and the PCM NO -Go to step 4
4. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
5. Disconnect the rocker arm oil control solenoid 1P connector
6. At the solenoid side, measure the resistance between the rocker arm oil control solenoid 1P connector terminal and the solenoid valve body Is there 14-30 ohms at room temperature? YES -Go to step 7 NO -Go to step 10
7. Jump the SCS line with the HDS
8. Disconnect PCM connector B (49P)
9. Check for continuity between PCM connector terminal B39 and body ground Is there continuity? YES -Repair short in the wire between the PCM (B39) and the rocker arm oil control solenoid, then go to step 11 NO -Go to step 18
10. Replace the rocker arm oil control solenoid (see «ROCKER ARM OIL CONTROL SOLENOID REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#vtec) )
11. Reconnect all connectors
12. Turn the ignition switch ON (II), or press the engine start/stop button to select the ON mode
13. Reset the PCM with the HDS
14. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#idle-control-system__pcm-idle-learn-procedure) )
15. Do the VTEC TEST in the INSPECTION MENU with the HDS
16. Check for Pending or Confirmed DTCs with the HDS Is DTC P2648 indicated? YES -Check for poor connections or loose terminals at the rocker arm oil control solenoid and the PCM, then go to step 1 NO -Go to step 17
17. Monitor the OBD STATUS for DTC P2648 in the DTCs MENU with the HDS Does the screen indicate PASSED? YES -Troubleshooting is complete If any other Pending or Confirmed 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 and the PCM, then go to step 1 If the screen indicates NOT COMPLETED, go to step 15
18. Reconnect all connectors
19. Update the PCM if it does not have the latest software (see «ECM/PCM UPDATE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) )
20. Do the VTEC TEST in the INSPECTION MENU with the HDS
21. Check for Pending or Confirmed DTCs with the HDS Is DTC P2648 indicated? YES -Check for poor connections or loose terminals at the rocker arm oil control solenoid and the PCM If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then recheck If the PCM was substituted, go to step 1 NO -Go to step 22
22. Monitor the OBD STATUS for DTC P2648 in the DTCs MENU with the HDS Does the screen indicate PASSED? YES -If the PCM was updated, troubleshooting is complete If the PCM was substituted, replace the original PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-replacement) ) If any other Pending or Confirmed DTCs were indicated in step 21, 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 and the PCM If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then recheck If the PCM was substituted, go to step 1 If the screen indicates NOT COMPLETED, go to step 20

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 (see GENERAL TROUBLESHOOTING INFORMATION )

Scheme 114

Scheme 115

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
2. Clear the DTC with the HDS
3. Start the engine Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T 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 5 NO -Intermittent failure, the system is OK at this time Check for poor connections or loose terminals at the rocker arm oil control solenoid and the PCM
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
6. Disconnect the rocker arm oil control solenoid 1P connector
7. At the solenoid side, measure the resistance between the rocker arm oil control solenoid 1P connector terminal and the solenoid valve body Is there 14-30 ohms at room temperature? YES -Go to step 8 NO -Go to step 11
8. Jump the SCS line with the HDS
9. Disconnect PCM connector B (49P)
10. Check for continuity between PCM connector terminal B39 and the rocker arm oil control solenoid 1P connector terminal Is there continuity? YES -Go to step 18 NO -Repair open in the wire between the PCM (B39) and the rocker arm oil control solenoid, then go to step 12
11. Replace the rocker arm oil control solenoid (see «ROCKER ARM OIL CONTROL SOLENOID REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#vtec) )
12. Reconnect all connectors
13. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
14. Reset the PCM with the HDS
15. Do the PCM idle learn procedure (see «PCM IDLE LEARN PROCEDURE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#idle-control-system__pcm-idle-learn-procedure) )
16. 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 control solenoid and the PCM, then go to step 1 NO -Go to step 17
17. Monitor the OBD STATUS for DTC P2649 in the DTCs MENU with the HDS Does the screen indicate PASSED? YES -Troubleshooting is complete If any other Pending or Confirmed DTCs were indicated in step 16, 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, keep idling until a result comes on
18. Reconnect all connectors
19. Update the PCM if it does not have the latest software (see «ECM/PCM UPDATE»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-update) ), or substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) )
20. Start the engine, and let it idle
21. 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 control solenoid and the PCM If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then recheck If the PCM was substituted, go to step 1 NO -Go to step 22
22. Monitor the OBD STATUS for DTC P2649 in the DTCs MENU with the HDS Does the screen indicate PASSED? YES -If the PCM was updated, troubleshooting is complete If the PCM was substituted, replace the original PCM (see «ECM/PCM REPLACEMENT»(/acura/tl/iv-2008-2011/remont/testing-diagnostics/#pgm-fi-system__ecmpcm-replacement) ) If any other Pending or Confirmed DTCs were indicated in step 21, 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 and the PCM If the PCM was updated, substitute a known-good PCM (see «SUBSTITUTING THE ECM/PCM»(/acura/tl/iv-2008-2011/remont/auxiliary-emission-control-systems/#fuel-and-emissions-systems__substituting-the-ecmpcm) ), then recheck If the PCM was substituted, go to step 1 If the screen indicates NOT COMPLETED, keep idling until a result comes on

Scheme 116

1. Disconnect the rocker arm oil control solenoid connector (A)
2. Remove the rocker arm oil control solenoid (B)
3. Install the parts in the reverse order of removal with a new O-ring (C)

Scheme 117

1. Disconnect the rocker arm oil pressure switch connector (A), then remove the rocker arm oil pressure switch (B)
2. Install the parts in the reverse order of removal with a new O-ring (C)

See also:
• GENERAL TROUBLESHOOTING INFORMATION
• PCM IDLE LEARN PROCEDURE
• ECM/PCM UPDATE
• SUBSTITUTING THE ECM/PCM
• ECM/PCM REPLACEMENT
• ROCKER ARM OIL CONTROL SOLENOID REPLACEMENT