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Ms2 temperature sensor problems
Ben_Copeland - 10/6/12 at 06:14 AM

Need a bit of advise please,

My ms2 doesn't seem to be reading the Intake temperature properly, infact it's stuck on 21oc.

It's was all working fine before, then suddenly it's just sat there.

I've unplugged the sensor and it stays the same, I've checked the wiring for resistance and nothing. I've checking inside the ms for anything obviously resistance wise but nothing. Is there something I'm missing here ?

Thanks

mark chandler - 10/6/12 at 08:52 AM

Dodgy plug maybe, identify the terminations within megasquirt and short out, you should then see the temp leap.

Showing 23 degrees is a little odd though, disconnected it would be below 0.

You could always try saving the config then reflash.

Regards Mark

Ben_Copeland - 10/6/12 at 04:35 PM

Its bazarre, if i put the signal cable to earth the temperature flicks but goes back to 21oc.

I'll have to try it with the cover off, and the cable disconnected from the ms plug.

Anyone else got any ideas?

mtechmatt - 11/6/12 at 12:29 PM

Hmm,

Is a bit odd, 21* is open circuit if calibrated to ford sensors.

I trust coolant is 100% ok?

Check the ground connection of the sensor, then try connecting to your coolant sensor and see what it reads.

If all connections are confirmed as 100% on, do the following:
1. Unplug the ECU
2. Read from the DB37 the resistance of the AIT sensor with recept to ground, and heat the sensor on the car, lighter beneath it, hot water etc, and see if the resistance changes at the DB37. If it does the problem lies further back in the ECU.


You can test the correct signal is reaching the MS2 Daughtercard by unplugging the card, and reading the voltage at Pin 24 pof the 40pin DIP socket with the ECU powered. You will see a voltage between 0-5v, based on the sensor temp. If this is OK, then the issue is the temo calibration on the MS2, or the duahtercard itself...

Let me know,
Matt @ M-Tech

Ben_Copeland - 11/6/12 at 12:37 PM

Hi Matt,

Yes coolant is fine, I'll recheck resistances but it's on GM sensors?! Not sure where open circuit for ford would come from.

Will update on checks tonight/tomorrow once I've done them

mtechmatt - 11/6/12 at 12:38 PM

Ah yes,

Sorry I'm thinking Ford, that is an open reading value for sure though, I think with ford (27K R4 and R7) you see 77* but its been ages since we have used V3 boards!


[Edited on 11/6/12 by mtechmatt]

Ben_Copeland - 11/6/12 at 07:34 PM

Matt, I get 3.08v which changes if you breath on it.


EDIT so say it now appears to be working. Although needs fine turning as its not 17oC but not far off.

[Edited on 11/6/12 by Ben_Copeland]

mtechmatt - 11/6/12 at 07:44 PM

So was it a case of removing./refitting the MS2 card? Must of ben an iffy connection somewhere. Glad its all working, let me know when you are ready for mapping

Ben_Copeland - 11/6/12 at 07:57 PM

quote:
Originally posted by mtechmatt
So was it a case of removing./refitting the MS2 card? Must of ben an iffy connection somewhere. Glad its all working, let me know when you are ready for mapping



Sent you a couple of emails earlier... Let me know if you didn't get them?

mtechmatt - 11/6/12 at 08:09 PM

Ah I'll get them tomorrow at work, will reply then..

Cheers