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View Full Version : Weirdness with outputs and CLT


JohnMc
07-15-2006, 11:50 AM
I stuck a 960 fan on my 240 yesterday. I hooked up the high speed to the high-temp sensor on my radiator, and the low speed to the A/C circuit (leaving the current pusher fan on for now, I'll remove it later). Drove it around and discovered (not unsuprisingly) that the high temp sensor only kicks the fan on hign when the needle is just under the red, and shuts back off when it only drops a little. I need sometihng to cycle the low speed on and off around the termostat's operating temp. One option would be the Saab hose fitting and a lower temp switch, but I thought I'd give MS a whack.

I soldered up one of the unused output circuits on the daughter board, using X2 as it seemed to be the one easier to set up for fan control.drilled another hole out of the case, installed a wire.

Next for the configuration, and that's where I ran into problems. On the Code Config-->Codebase and outputs function I set up X2 to Fan Control. Then under Shift/fan/Output 3+4 there are fan on and fan off temp settings. Set those up reasonably (190 on, 180 off, just to start with), and tweedled the CLT knob on the stim. Huzzah, I could get X2 (and the external wire I added) to turn on and off with the CLT knob. bad news, it pretty much always turns on at around 110 - 120 degrees and off at 210-220 degrees. No matter what temps I use for fan on and off.

So I tried setting up another output, without wiring it up physically yet, just to see if I could get it to work. But any output I configured to use CLT seems to operate in about the same manner, turning on at arond 110 - 120 degrees, and turning off at around 210 - 220 degrees, regardless of any temp settings or hysterisis settings. Even using vastly different temp settings, like 50 vs. 250, does the same thing. (I noticed output 4 seemed to flicker on and off rapidly, not a good candidate for running a fan). I even tried using IAT as a trigger, and they reacted the same way to the stim IAT knob, turning onn and off at the same temps regardless of settings. You could at least tell it was being triggered from the correct input, though.

Am I missing something obvious here? Anyone else successfully running a fan or other temp controlled output? Is this just an issue with the way the stim works? Would it work differently just because the stim can't simulate running/RPM?

I'm going to try updating the firmware to 029q, see if that helps at all.

kyle242gt
07-15-2006, 12:07 PM
So is it only goofy on the stim? Isn't there something in the MSnS setup that bogarts a ground that leads to inoperation on the stim? It might be only the rpm signal, now that I think about it though.

It also seems to me that sometimes those outputs need to be saved and rebooted/reloaded to take sometimes.

Have you tried it on the car yet? Might make a difference.

Oh - and one more thing that was screwy - be sure your thermfactor.inc file is right and is located where MT can find it (car1\mtcfg I think). I had an oddball temp sensor, and it stepped strangely through the temps, made setting the fan hard.

JohnMc
07-15-2006, 12:29 PM
Ahh, I just got done installing 029q, and now it works exactly as suspected. Turns on at the ON setting, stays on until it goes down to the off. Now to do a little light wiring (X2/daughter card output to low speed relay) and try it out.

swedefiend
07-15-2006, 12:34 PM
You might want to put a diode on that signal wire triggering the fan relay.

Flyback on large relays like that could give you problems.

JohnMc
07-15-2006, 07:04 PM
I ended up putting a small relay inbetween MS and the big fan relay. The big fan relay is powered all the time (so it can do a cooldown cycle if needed) and I was getting some sort of weird problem where MS would have an LED lit when turned off, and it didn't want to power back up. So I used a small relay that is only powered with the key on, worked fine.

Took it out for a test drive, 100 degree's and stifling here today, drove around for a while with the A/C blasting. the needle tended to rise up occasionally, every once in a while hitting the high temp/high speed threshold. But it never overheated, and the fan worked very well.

But for me the big news was 029q. Previously I was runing 025l, and it seemed rather crude. Occasional hiccups, sometimes if you pressed the gas down it would get stuck in a weird mode and leave the wideband pegged <10:1 and the engine sputtering, other times it would work properly and give you 12:1. And in general, the engine felt much rougher as it went through the rpm and map ranges, uneven, jerky, sometimes sputtery.

Same MSQ, 029Q and it is running a great deal more smoothly. And the wideband shows it to much more settled. The idle control even shows signs of actually doing what it is supposed to as well! w00t! Dunno why I waited so long, I guess I was just a little apprehensive about loading up new firmware.

PS - I unhooked D11 while I had it apart as well, maybe that's part of the smoother running? Probably not, but a more accurate WB02 reading can't hurt.

blkaplan
07-15-2006, 07:59 PM
Ahh, I just got done installing 029q, and now it works exactly as suspected. Turns on at the ON setting, stays on until it goes down to the off. Now to do a little light wiring (X2/daughter card output to low speed relay) and try it out.

did you have any problems getting 29q to work? whenever i tried to load it i couldn't get the car to start

JohnMc
07-15-2006, 10:00 PM
did you have any problems getting 29q to work? whenever i tried to load it i couldn't get the car to start
Just the slightly convoluted process needed to turn my old MSQ file into the new XML format. Other than that, it started right up. And then ran much better than before.