I have a 2000 Honda Accord EX Sedan and the automatic transmission shifter gets stuck in park and sometimes also gets stuck open where I can switch into gear without depressing brake pedal. I have so far tested and replaced the brake switch, although brake lights operate correctly, I tested the solenoid at the shifter and it works correctly, all mechanical parts on shifter are clean and work correctly. Using a multimeter I tested the green and yellow wires at the solenoid. It has constant 12 volts from the yellow lead. I checked the green negative lead which seems to be the wire that is switched and it is not working correctly. Sometimes it switchs when depressing the brake pedal and sometimes it does not. Also the 2 lighter gauge green and grey wires at the break switch which should be switching the negative current both have negative current to them. Which makes no sense to me. I gave up my search and brought it to the dealer and they told me to swap out the Drivers Side Multiplexor Unit, needless to say $95 for the diagnosis and $115 dollars for the part it also didn't work. I'm reluctant to return to the dealer for them to swap out parts until they find the problem. Hopefully somebody here can help me since there seem to be some good minds here. Thanks in advance.

 

unless there is a typo in there it sounds like the selenoid didn't test properly, do the brake lights still work even when you are unable to shift? Make sure that you are checking for lights when you are having the brake problem, have you checked the switch inside the shifter itself to make sure that it is releasing consistently?

 

If the dealer did the diagnose and replaced the part and the problem isn't fixed you need to call american honda customer service 1-800 # in your owners manual.
Also call and speak to the Service Manager, not the service writer. If that gets you no help ask for the General Manager of the dealership.
Be calm and polite to them while you let them know the dealer ripped you off.

 

I pulled the solenoid out and tested it with a seperate 12v source over and over again and it consistently worked properly. I reinstalled it and using the same 12v source I tested it in place and it continued to work properly. I then connected it back to the car source (green & yellow wires) and it went back to not working correctly. I tried the above again with the 12v source and it worked properly.
I then tested the yellow and green wires. The yellow is getting constant power and the green gets the sporadic negative power which seems to be how the solenoid gets switched.
Brake lights work when I'm having the shifting out of park problem. I manually tested and operated the switch inside the shifter and outside with no problems.
Thanks for the reply.
Hopefully we can figure this out..

 

Thanks HondaDude. Actually the service writer told me what the problem was and said since I was good with cars it would be easy enough for me to change myself. They wanted $189 for just the part where I ordered it from hondapartsdeals.com for $111. I made the parts switch and the problem continues. Now I have to send the part back.
This is my 4th Honda and it's been in my family since new. It has not acted like my other 3 Honda's thats for sure too many quirky problems for a Honda.

 

if you can go from park to a gear without stepping on the brake, that car falls into the saftey recall.
Or if the key can be removed while the car is in gear, it falls into the saftey recall

 

I called Honda directly and tried to tell them that it should fall into the safety recall for being able to put the car into gear without stepping on the brake, but since the dealer said it was the multiplexor and there is no recall for the multiplexor they said there was nothing they could do because I'm way out of the warranty. The recall seems to be for the ignition switch and my key doesn't pull out unless the car is in park so I guess it's working. I'm thinking at this point it could be an ignition switch short, a wiring issue or some sensor on the tranny isn't working. I've read elsewhere about a gear positon sensor but I don't know where it is or how I would test it. I'm gonna wait out the weekend on this forum and Tuesday I'll probably call the dealer and make an appointment. I can't afford to go to a dealer.
Do you or anyone else know how I can view complete technical bulletins and not just the quick descriptions you find on the NHTSA?

 

Igot 2 pdf files that might help you out some more, from just glancing thru, it seems there might be a ground problem thru the shift position switch
.
I'll have to upload them to my personal webspace and you should be able to 'right click' and "save as".

http://members.troublecodes.net/hond...hftintrlck.pdf

http://members.troublecodes.net/hond...ftintrlck2.pdf

This is the same info the dealers had so now you can figure out what they couldn't LOL

 

Thanks for the info, looks like I have a few more things to test if only I can locate everything. A whole lot of wires, switches, solenoids, modules, etc... for something I can get around by sticking a key through a small hole. I'm determined and will let you know how it goes. I like your thought on the bad ground through the shift position switch, I'll check that first.