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Is it possible??????

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Good day-evening to all of you guys,

last time I wrote to this forum I was wandering about senor ground gremlins this time around I want to ask about current changing direction :P

What I want to know is if I have 3 sensors sharing 5V and one fails is it possible for the sensors to report higher values because more current through them?

To specify my question even more what happened to me was that the IAT sensor cables failed but the opposite from what I ask happend!!!

Before the cable failure I had an issue that the TPS was reading more current than it supposed after the cable failure the TPS is reading correctly!

To specify even more factory IAT,CLT and TPS are common resistive sensors (Honda OEM-i think denso) When I added the ITBs on the car I had to replace the TPS with a digital one in order to fit it to the 6mm D shape actuator of the ITBs.

Additional info: IAT-2 cable sensor-Pin1: 5V-Pin2: signal to ECU, CLT-2 cable sensor-Pin1: 5V-Pin2: signal to ECU, TPS-3 Cable sensor-Pin1: 5V pin2: signal to ECU-Pin3 :GND 5V is common to all sensors

Are you sharing the same 5v circuit between a thermister (iat and clt) and a TPS? If so, you cannot do that. The 5v supply for a thermistor is also the signal, and if you share this same 5v wire with a TPS gou will get all sorts of weird TPS values.

As per Reinout's comments your wiring is very wrong if you have a 5V supply connected direct to a temp sensor. A temp sensor should be connected to either a dedicated temp sensor input (the pull-up/divider circuit is inside the ecu) or in rare cases to an analog volt input with an external pullup to 5V connected.

What ecu are you using? Does the manufacturer not provide any wiring information?

Thanks for the reply guys

The loom is the factory one and the ECU is the same. I'm using a daughterboard similar to hondata so the only thing I changes was the TPS and the position of the factory IAT! According to the schematics on the factory manual IAT, TPS and CLT share the 5V output! the signal have different inputs! Correct me if I'm reading this wrong! And on the factory manual when trouble shouting the factory TPS asks for resistance values!

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Correct me if I'm reading this wrong!

You are wrong. The shared green/white wire is the sensor ground.

And on the factory manual when trouble shouting the factory TPS asks for resistance values!

Yes, this is how most TP sensors work - they are a variable resistance potentiometer, if you put a fixed voltage on each end of a poteniometer (i.e. 5V), the variable resistor divides the 5V supply down to a variable voltage on the output pin.

Thanks Adam for correcting me but why my TPS was reading more voltage before the cable failure? Could it be a sensor failure?

Thanks again for your help! I hope I won't tire you with novice questions!

Its a bit hard to guess from the info you have given, but if the only change has been the wiring and the TPS now reads differently than it did previously then it suggests there was either a wiring problem before or there is a wiring problem now. If the hardware is all the same and nothing has been adjusted then the output voltage will be the same. The TPS is just a voltage divider so it will output a voltage directly proportional to its input voltage and angular position.

Update on my issue! I fixed the sensor cabling and everything is back to normal! sometimes the TPS gets higher values! My current guess is harness failure! I'll update when I have time to take out the harness as I daily drive the car! Right now everything reads ok!

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