SXTune Documentation
Documentation / Guides

ECU Setup

Temperature sensor setup

Calibrate NTC temperature inputs and verify them against known temperatures before using temperature-based corrections.

NTC inputs

The ECU uses NTC sensor scaling maps for coolant, air and other temperature channels. SXTune includes an NTC scaling tool that accepts temperature/resistance data and calculates values for the ECU's fixed breakpoints using the ECU's pull-up/reference arrangement.

NTC Sensor Calculator for temperature sensor scaling.
NTC Sensor Calculator for temperature sensor scaling.
Calculated sensor scaling applied to the ECU calibration.
Calculated sensor scaling applied to the ECU calibration.

Checks

At ambient temperature, compare ECU coolant/air readings with a reasonable independent temperature measurement. Check hot readings again once the engine reaches operating temperature. An incorrectly scaled temperature sensor can affect cranking fuel, warm-up fuel, ignition, boost, fan control and protection strategies simultaneously.