Honda

Have Honda questions? Ask a Honda repair expert.

Ask an Expert,
Get an Answer ASAP!

This answer was rated:

A friend brought over his 06 Honda Odyssey with the 3.5 V6,

auto tranny. We read the...
A friend brought over his 06 Honda Odyssey with the 3.5 V6, auto tranny. We read the codes, P2647. We checked the oil, level is good. When we start the car, it runs fine. We then accelerate and start driving. When sitting at a stop light, the engine will start to run rough and have no power. At that same time, the VSA light comes on. If you key off and then back on, it will run fine until the first stop light when it starts to run rough again.
Show More
Show Less
Ask Your Own Honda Question
Answered in 4 minutes by:
1/17/2018
Roy
Roy, Import/Domestic Specialist
Category: Honda
Satisfied Customers: 7,433
Experience: ASE Master Tech
Verified

hello, my name is ***** ***** I will be glad to assist you. please allow me a couple of minutes to gather some basic info.

Roy

Ask Your Own Honda Question

possible causes for the code below

P2647

ItemDescription

Symptom/DTCP2647

Descriptor

Rocker Arm Oil Pressure Switch Circuit High Voltage

Vtec System Struck On

Probable Causes

  • Engine Oil Level
  • Engine Oil Pressure (EOP) Sensor
  • Poor Connections or Loose Terminals At Engine Oil Pressure (EOP) Sensor
  • Poor Connections or Loose Terminals At Powertrain Control Module (PCM)
  • Poor Connections or Loose Terminals At Rocker Arm Oil Control Solenoid (VTEC Solenoid Valve)
  • Poor Connections or Loose Terminals At Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) and Powertrain Control Module (PCM)
  • Powertrain Control Module (PCM)
  • Powertrain Control Module (PCM) Update Needed
  • Rocker Arm Oil Control Solenoid (VTEC Solenoid Valve)
  • Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch)
  • Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) GND Line Open
  • Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) Open
  • Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) SIG Line Open
  • Wire Between Engine Mount Control Unit, Active Noise Control (ANC) Unit, Rocker Arm Oil Control Solenoid (VTEC Solenoid Valve) and Powertrain Control Module (PCM) C24 Shorted
  • Wire Between Powertrain Control Module (PCM) B23 and Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) Open
  • Wire Between Rocker Arm Oil Pressure Switch and G101 Open
Ask Your Own Honda Question
Customer reply replied 4 months ago
Engine oil pressure light isn't on.....would this mean it works? What is typically the item that needs to get fixed and where are those parts?
Customer reply replied 4 months ago
Are there 2 vtec valves...one on front head, one on rear?

each car has different resolutions. you need to have a scan tool and run through the tests to confimr.it usually has to do with the control solenoid.

what we do with this code to start is this. we get a bottle of sea foam and put it in the oil.let the engine idles for 1hour. then change the oil and filter. in a lot of cases, there is sludge in the oil system that is not allowing the oil control solenoids to pass the correct amount of oil

I would start there as this may resolve the issue without throwing parts at it as a guess.

Roy

Ask Your Own Honda Question
Customer reply replied 4 months ago
how many vtec valves and oil pressure sensors are there? Where are they located?

info on the code and location. do you have a scan tool to do the testing???

DTC P2647: Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) Circuit High Voltage

1. Check the engine oil level.

Is the level OK?

YES - Go to step 2.

NO - Adjust the engine oil to the proper level, then go to step 17.

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 (VTEC oil pressure switch) and the PCM.

NO - Go to step 5.

5. Check the result of step 4.
- Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) Failure
- Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) Open
- Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) SIG Line Open
- Rocker Arm Oil Pressure Switch (VTEC Oil Pressure Switch) GND Line Open

Did the test result indicate one of the above?

YES - Go to step 6.

NO - Check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil pressure switch). If it is OK, replace the rocker arm oil control solenoid (VTEC solenoid valve), then go to step 15.

6. Turn the ignition switch OFF.
7. Disconnect the rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector.

Zoom/Print

8. At the rocker arm oil pressure switch (VTEC oil pressure switch), check for continuity between rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector terminals No. 1 and No. 2.

Is there continuity?

YES - Go to step 9.

NO - Replace the rocker arm oil pressure switch (VTEC oil pressure switch), then go to step 15.

9. Turn the ignition switch ON (II).

Zoom/Print

10. Measure voltage between rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector terminal No. 1 and body ground.

Is there battery voltage?

YES - Repair open in the wire between the rocker arm oil pressure switch (VTEC oil pressure switch) and G101, then go to step 15.

NO - Go to step 11.

11. Turn the ignition switch OFF.
12. Jump the SCS line with the HDS.
13. Disconnect PCM connector B (44P).

Zoom/Print

14. Check for continuity between PCM connector terminal B23 and rocker arm oil pressure switch (VTEC oil pressure switch) 2P connector terminal No.1.

Is there continuity?

YES - Go to step 21.

NO - Repair open in the wire between the PCM (B23) and the rocker arm oil pressure switch (VTEC oil pressure switch), then go to step 15.

15. Reconnect all connectors.
16. Turn the ignition switch ON (II).
17. Reset the PCM with the HDS.
18. Do the PCM idle learn procedure.
19. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P2647 is indicated, check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil pressure switch) and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Go to step 20.

20. Monitor the OBD STATUS for DTC P2647 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete.

NO - If the screen indicates FAILED, go to step 1 and recheck. If the screen indicates NOT COMPLETED, go to step 18, and recheck.

21. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
22. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P2647 is indicated, check for poor connections or loose terminals at the rocker arm oil pressure switch (VTEC oil pressure switch) and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

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

more info

DTC P2647: VTEC System Stuck ON

Special Tools Required
- Pressure gauge adapter 07NAJ-P07010A
- A/T low pressure gauge w/panel 07406-0070300
- A/T pressure hose 07406-0020201
- A/T pressure hose, 2,210 mm 07MAJ-PY4011A
- A/T pressure adapter 07MAJ-PY40120
- Oil pressure hose 07ZAJ-S5A0200

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.

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 EOP sensor, the rocker arm oil control solenoid (VTEC solenoid valve), and the PCM.

NO - Go to step 5.

5. Turn the ignition switch OFF.

Zoom/Print

6. Remove the EOP sensor (A), install the special tools as shown, then install the EOP sensor in the oil pressure gauge adapter (B).

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

7. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle 2 minutes.
8. Do the VTEC TEST in the INSPECTION MENU with the HDS.
9. Check the oil pressure.

Does the oil pressure increase to 392 kPa (4.0 kgf/sq.cm, 56.9 psi)?

YES - Replace the EOP sensor, then go to step 10.

NO - Replace the rocker arm oil control solenoid (VTEC solenoid valve), then go to step 10.

10. Turn the ignition switch OFF.
11. Reconnect all connectors.
12. Turn the ignition switch ON (II).
13. Reset the PCM with the HDS.
14. Do the PCM idle learn procedure.
15. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle 2 minutes.
16. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P2647 is indicated, check for poor connections or loose terminals at the rocker arm oil control solenoid (VTEC solenoid valve), the EOP sensor, and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Go to step 17.

17. Monitor the OBD STATUS for DTC P2647 in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the EOP sensor and the PCM, then go to step 1 and recheck. If the screen indicates NOT COMPLETED, go to step 15 and recheck.

Ask Your Own Honda Question
Customer reply replied 4 months ago
Thanks for this info. Based on the picture, it looks like there is only one vtec valve and oil pressure sensor. Do you know if this is a 2 wire or 3 wire sensor...seems like it must be just a 2 pin from reading the above. Do you have a part number for theswitch? I do have a scan tool and I'll try this procedure tonight after work. Thanks,

I believe it is a 2 wire. I dont have the part number. you can get that from a parts store.

Roy

Please take a moment and rate my service 3 stars or better. that is the only way the site will pay me for my efforts.

Roy

Ask Your Own Honda Question

any update

Ask Your Own Honda Question
Customer reply replied 4 months ago
You stated the first thing you usually do is the seafoam in the engine oil. May I ask how many times have you done this and what % of the time is the issue resolved? Are there any negative issues that can arrise......ie loosening up other junk and causing the oil pump pickup tube to plug? Oil filter plug? Etc. Would an alternative be to remove the VTAC valve and clean individually. Do you have access to the wiring diagrams? I'd like to have the diagrams for any wire to the VTAC valve, vtac oil pressure sensor, engine oil pressure senser, pcm, etc

about 60% of the time it worked depending on the severity of the oil system being clogged with debris.

if the oil pick up was an issue, it would have an oil pressure issue.

there is no cleaning of the valves, replacement only. there areas that are clogged you cannot get to.

let me check on the diagram.

Roy

Ask Your Own Honda Question
Customer reply replied 4 months ago
My vtec oil pressure switch is a 3 pin, 3 wire. The diagram only shows 2. I think the VAN submodel is EXL - or something like that. Would it have a different sensor? Also, where is the PCM located on these? I'm not sure where your electrical diagrams come from...I've seen ones in the past from Alldata...if you are using Alldata I think they have a "powertrain management" schematic that will be many pages and contain the entire engine schematic...including connecting points....if you have that I would appreciate getting it. Thanks.

I have alldata and thats where it came from.

let me look again. there is no sub model listed as the engines and controls are the same.

Ask Your Own Honda Question
Customer reply replied 4 months ago
I've worked on the van a bit...and so far have not found the issue. We know it is not the pressure sensor....we replaced it and still have the issue. One thing I noticed on my scan tool is the regular engine oil pressure sensor was reading 10 psi at idle....I don't know if that is the correct pressure, but it seemed low to me. What is normal pressure at idle, hot engine?

minimum of 18-20 lbs.

Roy

Ask Your Own Honda Question
Customer reply replied 4 months ago
do you know if the computer uses that pressure along with the pressure on the vtec valve.....maybe that reading is low causing a fault. The engine sounds fine...no unusual noises. We'll probably install a gage and measure in parallel with the sensor.

the pcm does not control oil pressure. it controls the vtec solenoid to adjust cam timing. when the timing is not correct, the code sets

Roy

Ask Your Own Honda Question
Customer reply replied 4 months ago
My question was does the vtec system look at the other oil pressure sensor - the one usually by the oil filter....maybe compare that pressure to the vtec sensor.....

no, it does not compare the 2 readings. it only monitors the sensor at the solenoid

Roy

Roy
Roy, Import/Domestic Specialist
Category: Honda
Satisfied Customers: 7,433
Experience: ASE Master Tech
Verified
Roy and 87 other Honda Specialists are ready to help you
Ask your own question now
Was this answer helpful?
Ask Roy Your Own Question
Roy
Roy
Roy, Import/Domestic Specialist
Category: Honda
Satisfied Customers: 7,433
7,433 Satisfied Customers
Experience: ASE Master Tech

Roy is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

Thank you very much for saving my daughter and her family a lot of money on her Honda. You are definitely on my list for future help. Thanks, again.

FredUSA

I just heard from my mechanic. You were right...a $45.00 job. THANK YOU!! Your response was received in less than 10 minutes!!

Linda B.USA

Your answers were clear and the diagrams were perfect. Dealer wanted $87 for an hour of labor and even I did it in 15 minutes.

EdUSA

HONDA PLATINUM was great. I really appreciate his help. I was ready to trade my new Honda until he told me to wait until I got 3,000 miles on it and my gas mileage would get much better.

SummerUSA

I took the Power Steering O-Ring service bulletin linked from JustAnswer to my Acura dealer, and not only did they no-charge the o-ring, they also replaced the power steering pump at no cost.

Gary RStevenson Ranch, CA

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

< Previous | Next >

Meet the Experts:

Kyle N.

Kyle N.

Honda Master Tech

3,635 satisfied customers

Honda Dealer Tech, ASE Master Auto Tech

John G.

John G.

Honda Technician

2,643 satisfied customers

Dealership tech since 1982. ASE and Honda Master Technician.

Chris (aka-Moose)

Chris (aka-Moose)

Technician

531 satisfied customers

16 years of experience

Marty

Marty

Bosch Master Tech

131 satisfied customers

Bosch Certified Master Technician

Amedee

Amedee

Former ASE Master Technician

1,417 satisfied customers

ASE certified tech advanced level specialist. Wisconsin certified emissions state inspector

Ron

Ron

ASE Certified Technician

399 satisfied customers

ASE Certified Tech 34 years.

thebesthonda

thebesthonda

ASE MasterTechnician

2,299 satisfied customers

26 years experience

< Previous | Next >

Related Honda Questions
Honda Odyssey EX HONDA ODYSSEY 1995 With ignition switch
HONDA ODYSSEY 1995: With ignition switch 'OFF'; Day lights, electrical mirrors and heater fan are all powered; so, my battery get empty. We still have power on these equipments with ignition harness s… read more
Amedee
Amedee
Former ASE Master Technician
Vocational, Technical or Trade Scho
1,417 satisfied customers
my 2005 Honda Odyssey, air conditioning stopped blowing cool
my 2005 Honda Odyssey, air conditioning stopped blowing cool air, only hot. Van was running at the time., just went from cold to hot.… read more
MASTER TECH
MASTER TECH
Master Tech
Vocational, Technical or Trade Scho
4,807 satisfied customers
2007 odyssey..outside temperature reading.....Thanks
I have a 2007 odyssey and the outside temperature reading has apparently got stuck on 75 degrees. Any idea of why this might be? It is unfortunately near 100 here right now, not 75 degrees...Thanks… read more
VirtualWrench (L J)
VirtualWrench (L J)
Owner of LJ Auto Repair 37 years
Associate Degree
38 satisfied customers
I have a 2007 Honda Odyssey with Navi and DVD Player. Well
Hi! I have a 2007 Honda Odyssey with Navi and DVD Player. Well my child has tried to shove to many discs in that it is not loading or ejecting. I was able to get one cd out but I think there is anothe… read more
Anthony P.
Anthony P.
high school
352 satisfied customers
I have a 2007 Honda Odyssey that has a door locking issue
I have a 2007 Honda Odyssey that has a door locking issue with both the key fob and master switch on the drivers door. … read more
Anthony P.
Anthony P.
high school
352 satisfied customers
No ecm communication no ac. 2006 odyssey. No someone else
no someone else just put motor in. check all fuses I could find, hot wire compressor to ck compressor . It works but no cooling fan so pressure goes to high of corse … read more
Anthony P.
Anthony P.
high school
352 satisfied customers
Fob on 2014 Honda Odyssey will not start car, at all. Don't
fob on 2014 Honda Odyssey will not start car, at all … read more
Anthony P.
Anthony P.
high school
352 satisfied customers
I have 2006 odyssey, and the parking light does not turn on
I have 2006 odyssey, and the parking light does not turn on even I turn on the headlight. … read more
Anthony P.
Anthony P.
high school
352 satisfied customers
Slide in door won't close. Odyssey 2010. No not fixing
Slide in door won't close. JA: What is the model/year of your Honda? Customer: Odyssey 2010 JA: Are you fixing your Odyssey yourself? What have you tried so far? Customer: No not fixing myself.forse i… read more
Anthony P.
Anthony P.
high school
352 satisfied customers
I have a 2007 Honda Odyssey and the windshield washer
I have a 2007 Honda Odyssey and the windshield washer nozzles need to be replaced, they are blocked or broken, can you give me instruction and part numbers please, thanks… read more
Eric
Eric
Retired
N/A
14,436 satisfied customers
I purchased a 2014 Honda Odyssey in November 2017. It is
I purchased a 2014 Honda Odyssey in November 2017. It is extremely difficult to remove the gas cap. Why? … read more
Anthony P.
Anthony P.
high school
352 satisfied customers
03 Odyssey Will not start sometimes. It takes turning the
03 Odyssey Will not start sometimes. It takes turning the ignition to on only, with brake pressed, and moving the shifter from park to neutral and then back before going to start position on ignition … read more
Anthony P.
Anthony P.
high school
352 satisfied customers
Odyssey. 2002 looking for ect sensor location. Engine
odyssey JA: What year is your Odyssey? Customer: 2002 looking for ect sensor location JA: Which particular sensor are you asking about? And have any trouble codes been triggered? Customer: engine cool… read more
Eric
Eric
Retired
N/A
14,436 satisfied customers
2006 Honda Odyssey van will not start, shift gears or
2006 Honda Odyssey van will not start, shift gears or release key. I disconnected battery and pressed gear release tab next to shifter and key came out. Plugged battery back up and attempted again wit… read more
Anthony P.
Anthony P.
high school
352 satisfied customers
I need immobilized brake code for my Honda Odyssey
I need immobilized brake code for my Honda Odyssey … read more
David Craig
David Craig
OWNER/MECHANIC
Associates
5,271 satisfied customers
What's the lifespan of axle of 2008 honda odyssey. my
what's the lifespan of axle of 2008 honda odyssey. my odyssey is 260k miles … read more
Honda-Man
Honda-Man
Associate Degree
3,125 satisfied customers
2000 Honda Odyssey air conditioning is no longer c
2000 Honda Odyssey air conditioning is no longer cooling.… read more
Kevin Bourcier
Kevin Bourcier
Vocational, Technical or Trade Scho
385 satisfied customers
Odyssey: 2005 alarm has been going off
My 2005 Odyssey's alarm has been going off for no apparent reason. The first time it went off I couldn't use the remotes so i changed the batteries, this didn't work but i was able to get in using the… read more
Honda-Man
Honda-Man
Associate Degree
3,125 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x