A/C worked with Stock ECU but having AC issues with MS3PNP
 

Hi All,

When my car was stock, my AC functioned perfectly and being in Northern VA, I enjoy having it. Ever since going the turbo route and installing a MS3Pro PnP, my AC has stopped functioning. Recently, I received it back from a RMA to DIYAutotune where my issue was identified as a tune issue. My AC Idle-up Input was not correct (I had it on 'Digital Switched In' 2 when it should have been 3). DIY's Matt Cramer identified the issue and gave the feedback. Upon receiving the ECU, I changed the Input setting to the correct one, 'Digital Switched In' 3 and the AC compressor now activates when I press the HVAC AC button - Yay!
Unfortunately, the AC fan does not turn on. From reading DIY's Install manual for my ECU, the Output for the secondary fan is 'Injector Out' I (i). I changed the setting in tunerstudio and burned it. Now the fan activates with the HVAC AC button but the compressor no longer turns on. I changed the Output back to 'J' and burned it. The AC compressor activates but no fan again. Matt recently mentioned changing my Fan Control settings and to enable the "Fan On With AC On" setting which turns the main fan on but not the AC fan. I also attempted a Programmable On/Off for the ac fan but couldn't find a good algorithm.

Just to recap - When I press my AC button, I can either have the AC compressor turn on without the AC fan or I can have the AC fan turn on without activating the AC compressor. Needless to say, I'm lost at next steps.

I attached my Tune msq. I planned to take video of everything so I could prove I'm not losing my mind but my tuning laptop decided to flake out on me. Please let me know if I'm still missing something or if I should work on uploading the video evidence.

Thank you.

You need to enable a programmable output (Injector I) that turns on whenever Injector J is on.

Hey Reverant,

Thanks for the advice. I'm looking through the Programmable On/Off Outputs 1 options but I don't see an obvious Injector J Output channel among the list of Output channels for the Active Condition when Injector I is Active. Am I overlooking it?

I found a document on MSExtra with some information. I attached a screenshot of the information I found and a Programmable output based on what I think the information is telling me. Am I understanding this correctly?

https://cimg1.ibsrv.net/gimg/www.mia...42f8d96a10.png

Looks like you have it. I have a MS3x and I wired INJF to be my pass side fan. I control it the same way and I use the same instruction to show an indicator if the fan is on or off.
In your screen shot it is saying that whenever INJ is on, which = 8, then the fan will turn on. It will also turn on any time the CLT sensor gets to 200. In my case my main fan comes on at 195 using Fan Control and I use the above method to make my pass side fan come on at 196. I do this so they don't end up starting at the same time with a combined initial draw of current. I also use 5 in Hysteresis on the coolant line so it shuts off 1 degree before the main fan.

Thanks for the insight, natewin. I'll burn this in and see how it goes. I appreciate your input - will update on results

Unfortunately the portt = 8 setting did not turn the fan on. I'm not sure if it should read differently within the condition statement. I was able to activate the fan with coolant temp so its obviously functional.

Any idea on how to validate the portt interaction?

Try Status7 = 32 maybe? That is how the AC gauge indicator works in Tunerstudio.

PORTT AND 8 = 8

Thanks natewin and Reverant for the input.

Reverant, I ended up using your syntax recommendation and that resolved the issue. I greatly appreciate you sharing your knowledge - this has been an ongoing issue for me and I can finally sleep better at night now that it has been fixed

Thanks again!

degooey, can you show your final settings? I'm confused by the 8=8 part. What you have in your earlier post looks like it makes sense to me, but you said it didn't work.

Hey mikep554. It was also confusing for me but I looked it up and got a good explanation from this msextra manual: http://www.msextra.com/doc/pdf/Megas...ing_Up-1.5.pdf - Section 4.32.1 Bitwise operations.

Essentially when you use the AND operation, it changes the meaning of the entire syntax. Here is how I have mine which works to turn my FAN2 on when my AC is activated:
https://cimg4.ibsrv.net/gimg/www.mia...419e3a14b7.png


There is a great example in the msextra document. Perhaps someone smarter than me could also chime in. Hope you find this helpful.

That's perfect, thanks everyone!