Announcement

Collapse
No announcement yet.

Temp sensor correction

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • Temp sensor correction

    I have 2 temp sensors I bought almost 2 years ago with my FB Version 3. They are sitting right next to each other but separated by a 2 degree difference? Any way to correct this?

  • #2
    same issue here- except 3 sensors and 6 deg total difference
    TruckPC - gutted, being used for test setup
    BoatPC - All in 1 in cuddy, N7 using VNC on dash, RR
    BlazerPC - Nexus 7 with Timur's USBROM

    Comment


    • #3
      You could certainly change the formulas in MDX. You'd probably want to calibrate against a high $$$ thermometer, though.

      Comment


      • #4
        Got ya. I finally put my FB in the car today and installed the sensors. Everything seems good except where I mounted the exterior (outside) sensor. I followed an example listed in another post about going through the floor and near the spare tire underneath my SUV. To my delight there was a pre existing hole about an inch diameter covered with an insulating style tape. I poked a whole through and stuck the sensor out, hot glued it and tested. My PC is located in the rear as well. I do not have any extenders for the sensors. I idled thew vehicle for 20 minutes and to my expectations the temp read 110 F where as the actual outdoor temp is 93 F. It is too influenced and thrown off by ambient heat from mechanical and exhaust components. At least I have an easy path to exit the interior. It is clear I need to buy some extensions and run it some where better.

        My question is when I add 1 or 2 extensions this will change the accuracy of the reading, correct?

        And when can we expect the the 3 pin extensions back in stock? They have been out forever it seems.

        Comment


        • #5
          I can be blamed for them being out of stock...i bought the last 14 they had. So far I have not noticed much variance with adding extensions to the temp sensors... maybe 1degree, which for most is quite acceptable. I have several temp sensors installed in my car already. 1 forward of the radiator, ziptied to the car's factory ambient air temp sensor, another that I put into my air filter using a plastic bushing and electrical tape(to take up the space difference between the two), another in my engine coolant, another in the engine oil, and another inside the cabin hidden in my driver seat on the backside... my carpc is behind the driver seat and to the sensors in the engine bay i have 4 extensions each...

          The only time i get any kind of radiant heat interference with the sensor forward of the radiator is when my AC is on...otherwise it stays steady for about 10 minutes until the front bumper area is finally heat-soaked from the radiator...

          once I do my motor swap, I will also have a turbocharger, to which I'll be adding 2 more temp sensors (one before and one after the FMIC), as well as tapping into more of the stock sensors (MAP, TIP, etc), so get extensions as fast as you can before i buy them all again, lol
          Planning: [|||||||||-] 90%
          Purchased: [|||||||||/] 99%
          Installation: [|||||||||-] 90% (when is anyone's project ever REALLY done...)

          Comment


          • #6
            The extensions do throw off the accuracy, but it is the same all the time. Meaning you can adjust the reading based on what it should be and that adjustment should work over all temperatures.

            Also, we have a bunch of extensions and other cables in stock now. But mp3car is handling all the shipping right now. The main person in charge of ordering things I guess is on vacation, but I am sure if you email the store, they will in turn email me asking for some.
            Fusion Brain Version 6 Released!
            1.9in x 2.9in -- 47mm x 73mm
            30 Digital Outputs -- Directly drive a relay
            15 Analogue Inputs -- Read sensors like temperature, light, distance, acceleration, and more
            Buy now in the MP3Car.com Store

            Comment


            • #7
              Originally posted by 2k1Toaster View Post
              The extensions do throw off the accuracy, but it is the same all the time. Meaning you can adjust the reading based on what it should be and that adjustment should work over all temperatures.

              Also, we have a bunch of extensions and other cables in stock now. But mp3car is handling all the shipping right now. The main person in charge of ordering things I guess is on vacation, but I am sure if you email the store, they will in turn email me asking for some.
              Sounds good, maybe if I ever get the sensors and some one else doesnt buy them all first, Haha, I'll take a look at adjustments.

              Comment


              • #8
                hey hey, i only bought the rest of the extensions, lol...

                i need more though...i ordered 15 and they only had 14, and i'll need at least another 20 by the time i'm done........if that's even possible...
                Planning: [|||||||||-] 90%
                Purchased: [|||||||||/] 99%
                Installation: [|||||||||-] 90% (when is anyone's project ever REALLY done...)

                Comment


                • #9
                  I meant extensions not sensors
                  ..20 more?? What are u doing? Ever think about obd?

                  Comment


                  • #10
                    i have considered it yes... but from what i've seen so far you cant get the info to show up on every screen..... mine displays cabin and outside temp on every screen except my port config screens...

                    so far I'm monitoring ambient temp, intake temp, cabin temp, coolant temp, oil temp, and throttle position. soon i will also be monitoring vehicle speed and tach. my car thinks i'm going slower than I really am because of the tire size i'm running. I drive a dodge neon that came with 185/65r15's stock. I've since upgraded the suspension, brakes, and tires to SRT4 spec (at least, tire diameter). I now run 225/40r18's, which throw the speedometer off 1mph every 15mph (15 is 16, 30 is 32, etc).

                    Eventually I'm going to do an SRT swap and have the turbo motor, transmission, etc, to which I will add even more sensors into the mix including oil pressure, fuel pressure, pre-fmic and post-fmic temp sensors, 3bar map sensor, 3bar tip sensor, etc... A lot of those things can't be monitored using OBD software...
                    Planning: [|||||||||-] 90%
                    Purchased: [|||||||||/] 99%
                    Installation: [|||||||||-] 90% (when is anyone's project ever REALLY done...)

                    Comment


                    • #11
                      Wow. I stand down sir obd certainly wouldn't fulfill those needs

                      Comment


                      • #12
                        yeah......some can like coolant temp, intake temp, ambient temp, and tach signal, but the rest really......at least not something that i can use...

                        the biggest thing is i'm using the values i get back from the sensors to determine what i want the car to do..... I'm going to program in a bypass of the stock computer's rad fan control using the coolant temp sensor, automate my HVAC, create a remote starter using the carpc, and once i'm boosted and reading the map and tip sensors...electronic boost control through the CarPC...
                        Planning: [|||||||||-] 90%
                        Purchased: [|||||||||/] 99%
                        Installation: [|||||||||-] 90% (when is anyone's project ever REALLY done...)

                        Comment


                        • #13
                          To me that is a more effective way. You wont deal with the delay and latencies of obd. I'd really be interested in how u do the remote starter.

                          Comment


                          • #14
                            Originally posted by Dougw133 View Post
                            To me that is a more effective way. You wont deal with the delay and latencies of obd. I'd really be interested in how u do the remote starter.
                            Well first off, I built a circuit board with some tiny relays on it. This board is what provides the ignition signal for the M4ATX. It uses IGN, ACC, and all door unlock pulse from the remote keyless entry module. Using just some simple diodes I created a latching relay for the unlock pulse so that even when the signal is gone, the carpc can keep running.

                            This is the code for the remote start. In my settings screen, i have an on/off switch w/ indicator for remote start. RSCHECK is the command that checks to see if that variable has been set to true. If it's true, it goes through and starts the car. First it turns on the ignition for 4 seconds to let the fuel system pressurize, then blips the starter for the time specified in the settings (in my case .75s). Unfortunately this is not fool proof yet. Once I have my tach signal working, I will add in a timer that after 2 seconds after the starter pulse tach signal is not above 0, that it will retry starting...right now it'll just assume the car's running and thats it...

                            Code:
                            "RSOFF","GblTmr_Del;RSRUNTIME||DIGITALOUT$O2P$;RELEASE"
                            "STARTEROFF","DIGITALOUT$O1P$;RELEASE"
                            "STARTERON","DIGITALOUT$O1P$;HOLD||GblTmr_Add;STARTEROFF;$TIMER4$;STARTEROFF;oneshot||GblTmr_Del;STARTERWAIT||GblTmr_Add;RSRUNTIME;$RSTMRLEN$;RSOFF;oneshot"
                            "STARTCAR","DIGITALOUT$O2P$;HOLD||GblTmr_Add;STARTERWAIT;4;STARTERON;oneshot"
                            "RSCHECK","EVAL;RSTMRLEN;$TIMER2$*60||BYVAR;REMOTESTART;<<STARTCAR<<"
                            I'm sure the RRFusion stuff looks a bit funky and that's because i have a custom setup where in RR i can define what options and what inputs are on what ports on the fusion brain...



                            I have 4 pages that look like that...2 for outputs, 2 for inputs...

                            Right now i only have 1 brain in the system (and that screenshot was taken on my desktop, not the carpc)...if i can get/help shaun finish up his multi-brain RRFusion, then i'll be able to do everything I want to do.....until then I'm running low on ports, lol. If he cant do it then I'm going to have to convert to just using MDX, which is going to be interesting...
                            Planning: [|||||||||-] 90%
                            Purchased: [|||||||||/] 99%
                            Installation: [|||||||||-] 90% (when is anyone's project ever REALLY done...)

                            Comment


                            • #15
                              That is awesome man really. Nice work!

                              Comment

                              Working...
                              X