8H - e30 - s52swap - S50 harness and sensors | AEM
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Last seen: 3 years 10 months ago
Joined: 10/12/2016 - 19:42
8H - e30 - s52swap - S50 harness and sensors

I am having issues with the TPS and IAT sensors not reading correctly in the Infinity.  

  • TPS is getting 5v From infinity, TPS signal wire shows .5 coming out, Infinity sees 5V for the sensor input always 
  • The IAT is not getting any voltage and has no reading
  • However, the Coolant temp sensor is getting 5V and is reading correctly in the AEM, which is on the same loop
  • AEM has been sent in and tested in full working order
  • MAP sensor circut working and funtioning correctly 
  • Harness was fully rebuilt and using a Boomslang PNP adapter.  Pinout vs Harness have been confirmed

So far I have tested continuity for the following 

  • sensor inputs to all sensors are good and pinout is correct
  • AEM sensor ground pin to all sensors is good, with OL reading to chassis grounds or any other pins
  • 5V sensor suppy to TPS is good
  • All sensors test within OEM resistance specs
  • All AEM power ground pins to chassis ground is good
  •  AEM recieveing 12v to Permanent power, ignition switch pins as required.
  • TPS signal wire to AEM TPS input plug is good


I'm lost as to why the TPS could be showing the constat 5v input vs the .5 that the signal wire is showing at the sensor, and why the IAT is not getting any voltage when it is on the same loop as the other two sensors.  Any help or ideas for further testing would be awesome!