d0lph1n

By default, with the Sport or PSE button on, the DME will turn off the sport exhaust between certain speeds.

So far, there are few solutions:
1. Unplug the wire harness of the PSE solenoid
2. install an extra button to disconect one of the wires between DME and the PSE solenoid.
3. A wireless solution

My goal is to combine the solution 1&2 without installing an extra button.

A simple relay that detects when the Sport or PSE button's LED is ON...and it will disconnect the wire(s) between DME and the PSE solenoid. So the PSE valves will remain fully open until the PSE button is pressed again.

Question: Where can i find the DME 7.8 pinout for 2005 997 C2 coupe?

jhbrennan

Not sure what you're trying to do...but if you're intent is to have PSE "on" all the time, there is an easier solution.

d0lph1n

I'm trying to achieve the followings:
- maintain the control of over the PSE valves. PSE / On all the time is not a solutions for me. (Ex: I need PSE off, usually in the mornings)
- no extra button(s) to press to disable the DME control over the PSE valves. Installing an extra button...or the remote control switch involves and extra step....that could be avoided

In my case (tiptronic), having the exhaust on without Sport mode ON..doesn't make any sense.

larrytrk

Leave the PSE switch off in the morning, default should then be off anyway !
As soon as you start the car, the solenoid is activated to shut off the valves, if the switch is off.
Don't you have the PSE button on the dash?

jhbrennan

I'm still unclear what he's trying to accomplish. Start the car in the morning, PSE is already defaulted "off". Drive out of the neighborhood, push PSE button and PSE is "on". What are we missing?

d0lph1n

My first post was confusing. I've updated it.

By default, with the PSE /Sport button on, the DME will override the PSE, it will turn off the sport exhaust between certain speeds, correct?

I'm trying to prevent that with no extra button. By instaling a relay that detects when the PSE button is ON and disconnects the wire(s) between DME and the PSE solenoid simulating a wire harness unplug of the solenoid.

For now, i'm trying to find the DME 7.8 pinout for 2005 997 c2 coupe.

jhbrennan

OK - thanks - I think I understand what you want to do. With no PSE mufflers why do you think you have PSE? Have you checked the tail pipes - that's usually a good visual indicator that you have PSE. What you're describing sounds like Sport mode which you can have without have the PSE option.

d0lph1n

I do have PSE mufflers. And you are correct, the car came with Sport Chrono, Sport button..I added the PSE mufflers & wiring.

Anyway, do you have the DME pinout or schematics?

d0lph1n

I found the proper schematics. According to these schematics:

- The Sport button's LED is connected to "CU On Board Comp. Network"
- the "CU On Board Comp. Network" in located on the left driver's side via a Ye/Ye cable.

Could help me locate the "CU On Board Comp. Network, please? Any visual clues?

jhbrennan

Wish I could help...you're a brave man to go in to the electronics and try to make changes.

I think I finally figured out your goal - when PSE is on, you want to eliminate the PSE feature that shuts PSE off between 45kph (28mph) and 75kph (47mph) - IIRC, that feature is there to comply with Euro (specifically Swiss) noise abatement. That is such a narrow mph band that personally I wouldn't try to modify any of the electronics. I run my PSE on all the time and have never had any neighbor complaints over 8 years. Good luck with your project.

d0lph1n

Thank you.

Let me add:
- I drive my car every day, windows open, car stereo off. It's my daily driver. Most of the driving can be considered city driving. That's exactly the sweet spot when the PSE is cut off.

- If you run the PSE off all the time, I invite you to connect it again to the DME and drive it around the city. You'll might be surprised how much impact it has on car's sound and on the entire driving experience up to highway speeds where you can't hear it as much...bcz of the wind noise (open windows) and road noise.

- I can't have PSE off all the time bcz I usually leave the house around 8am and my neighbor's bedroom is 20ft away from my car's exhaust. I could try not to give a damn but I don't think it's fair. One more issue, not sure if it's true or not, I've read that the PSE valves, especially their vacuum membrane need a regular on/off exercise.

- Bcz I installed the PSE mufflers myself, I don't consider this new project as difficult. The more I gather info about it, the easier it seems. Btw, I already can see the Sport's button's LED wire (Ye/Ye) that I have to tap into and I know the other two wires that control the PSE valve (I installed them).

nwGTS

Let me just say that if you attempt this, for posterity and all of us who have PSE, please, for the love of God, do a DIY thread.

stronbl

Wow. An interesting project. Have you investigated using a Durametric Pro to re-code the DME w/ PSE to achieve the desired results? I'm not sure it can be done, but with the 997.1 & 997.2 cars, Durametric Pro is very versatile. Might be worth checking out to determine if it is feasible.

d0lph1n

I don't have access to a Durametric Pro and the last time I checked, it can't be disabled from DME not even with a software upgrade like Softronic and Evoms. Maybe it can be done with a real PIWIS, I' would gladly pay for this mod.

ChicagoSpeed996

I just did the switch mod, it cost me all of $4.59 for a switch at radio shack and some wiring I had laying around, oh, and time. Works like you want it to work, but without the complication.