# IAT Wiring Issue **URL:** \ **Category:** EMU BLACK / CLASSIC\ **Tags:** wiring\ **Created:** [July 2, 2024, 8:19am UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733 "2024-07-02T08:19:30Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![GC8\_Lover](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/gc8_lover/32/1097_2.png) [@GC8\_Lover](https://community.ecumaster.com/u/GC8_Lover)\ **Post date:** [July 2, 2024, 8:19am UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/1 "2024-07-02T08:19:30Z")
Hi, I recently got a Bosch AIT for my emu black. It has only two wires. I connected one end to IAT input and the other to “Sensor Ground”. My problem is that even if I connect the wires the other way around, I still get a constant voltage reading. It doesn’t work. Did I connect the wires poorly? How is it meant to be wired up exactly? Side note: A shop did the wiring for me, and he used the OEM harness, so I don’t know how he connected the grounds exactly. All I know is that he cut up some wires from my harness, and hooked them up to the ECU. I was thinking that maybe I should connect one of the cables to the car ground, but I’m unsure if that would help. Any help is welcome, thank you 🫡 ---
**Author:** ![derUltraTT](https://avatars.discourse-cdn.com/v4/letter/d/ba8739/32.png) [@derUltraTT](https://community.ecumaster.com/u/derUltraTT)\ **Post date:** [July 2, 2024, 11:58am UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/2 "2024-07-02T11:58:04Z")
If u connect pin1 or pin2 to ground/ECU doesn’t matter for such a sensor. Also should it work independed if u connect it to sensorground or vehicle ground. But u need pullup…did u select this option? If yes, then ur sensor is broken or ur wiring is not as u think it is. ---
**Author:** ![GC8\_Lover](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/gc8_lover/32/1097_2.png) [@GC8\_Lover](https://community.ecumaster.com/u/GC8_Lover)\ **Post date:** [July 2, 2024, 12:14pm UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/3 "2024-07-02T12:14:39Z")
My settings look like this. Is there anything I should try differently? ![image](https://europe1.discourse-cdn.com/flex013/uploads/ecumaster/original/2X/2/2b970de89f78e475ad488321fe7a684796ea16d4.png) ---
**Author:** ![derUltraTT](https://avatars.discourse-cdn.com/v4/letter/d/ba8739/32.png) [@derUltraTT](https://community.ecumaster.com/u/derUltraTT)\ **Post date:** [July 2, 2024, 12:36pm UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/4 "2024-07-02T12:36:08Z")
Ur settings are correct. I think u should check ur wiring next. What reading do u currently get? ---
**Author:** ![GC8\_Lover](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/gc8_lover/32/1097_2.png) [@GC8\_Lover](https://community.ecumaster.com/u/GC8_Lover)\ **Post date:** [July 2, 2024, 12:46pm UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/5 "2024-07-02T12:46:49Z")
Let me go down the car and strip the interior, and I’ll double check my readings and wiring. Then, I’ll post the info here later this evening ---
**Author:** ![derUltraTT](https://avatars.discourse-cdn.com/v4/letter/d/ba8739/32.png) [@derUltraTT](https://community.ecumaster.com/u/derUltraTT)\ **Post date:** [July 2, 2024, 12:50pm UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/6 "2024-07-02T12:50:42Z")
Ah and what happens when u disconnect the sensor?..does the reading then change? ---
**Author:** ![GC8\_Lover](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/gc8_lover/32/1097_2.png) [@GC8\_Lover](https://community.ecumaster.com/u/GC8_Lover)\ **Post date:** [July 2, 2024, 12:54pm UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/7 "2024-07-02T12:54:15Z")
When disconnected, it reads permanently about 25C. And connected, it constantly reads between 2.00v - 2.41v if I remember correctly, and shows a reading of 30C. But the temp never goes up or down even if the voltage of the sensor changes ---
**Author:** ![derUltraTT](https://avatars.discourse-cdn.com/v4/letter/d/ba8739/32.png) [@derUltraTT](https://community.ecumaster.com/u/derUltraTT)\ **Post date:** [July 2, 2024, 2:20pm UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/8 "2024-07-02T14:20:12Z")
Okay that is very strange…sounds like ur characteristiccurve is not correct. Can u show ur characteristic curve? ---
**Author:** ![GC8\_Lover](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/gc8_lover/32/1097_2.png) [@GC8\_Lover](https://community.ecumaster.com/u/GC8_Lover)\ **Post date:** [July 2, 2024, 2:37pm UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/9 "2024-07-02T14:37:53Z")
I can’t find a map save from the time I was tinkering around with the IAT config right now. It’s been a while. So I’m unsure if the data I have it correct or not regarding the calibration map I won’t be able to look at the wiring until tomorrow, but when I do, I will use the wizard to setup the sensor again, and connect the cables and see how it behaves like. I’ll post an update once I do those ---
**Author:** ![GC8\_Lover](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/gc8_lover/32/1097_2.png) [@GC8\_Lover](https://community.ecumaster.com/u/GC8_Lover)\ **Post date:** [July 5, 2024, 5:04pm UTC](https://community.ecumaster.com/t/iat-wiring-issue/1733/10 "2024-07-05T17:04:45Z")
One last update on this thread; I checked the wiring and it was correct. You were right, I forgot to apply the curve map using the sensor wizard. I guess when I connected the sensor, I opened the wizard, and just closed it after seeing the correct model there (NTC M12-L). I can confirm that on a cold engine, in the shade, it was showing 27°C. When the CLT went up to 90°C, my IAT was showing 36°C. It’s working right now. Thank you for your help 🤝 @derUltraTT